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data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Engine_balance" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Engine_balance"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Engine balance</span> </div> </a> <ul id="toc-Engine_balance-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Use_in_aircraft" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Use_in_aircraft"> <div class="vector-toc-text"> <span 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title="Flat-six">Flat-six</a>)</span></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Horizontally opposed 6-cylinder piston engine</div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">"Flat-six" redirects here. For the interval, see <a href="/wiki/Minor_sixth" title="Minor sixth">Minor sixth</a>.</div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Continental_O-470-13A.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/b/be/Continental_O-470-13A.jpg/220px-Continental_O-470-13A.jpg" decoding="async" width="220" height="140" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/be/Continental_O-470-13A.jpg/330px-Continental_O-470-13A.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/b/be/Continental_O-470-13A.jpg 2x" data-file-width="431" data-file-height="274" /></a><figcaption><a href="/wiki/Continental_O-470" title="Continental O-470">Continental O-470-13A</a> air-cooled aircraft engine</figcaption></figure> <p>A <b>flat-six engine</b>, also known as a <b>horizontally opposed-six</b>, is a <a href="/wiki/Six-cylinder" class="mw-redirect" title="Six-cylinder">six-cylinder</a> <a href="/wiki/Internal_combustion_engine#Reciprocating_engines" title="Internal combustion engine">piston engine</a> with three cylinders on each side of a central <a href="/wiki/Crankshaft" title="Crankshaft">crankshaft</a>. The most common type of flat-six engine is the <b>boxer-six</b> engine, where each pair of opposed cylinders moves inwards and outwards at the same time. An alternative configuration for flat engines is a 180-degree V engine, where both cylinders move to the right then the left at the same time. </p><p>The advantages of the flat-six layout are good engine balance (for reduced vibration), a low center of gravity, short length (compared with an <a href="/wiki/Inline-six_engine" class="mw-redirect" title="Inline-six engine">inline-six engine</a>) and being well suited to air-cooling. The disadvantages are a large width (which can limit the maximum steering angle when used in a front-engined car), a large intake manifold being required when a central <a href="/wiki/Carburetor" title="Carburetor">carburetor</a> is used, and duplication of the inlet and outlet connections for water-cooled engines.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p><p>The first production flat-six engine was in the 1904 <i><a href="/wiki/Wilson-Pilcher" title="Wilson-Pilcher">Wilson-Pilcher</a> 18/24 HP</i> car. The most notable use of flat-six engines is the <a href="/wiki/Porsche_911" title="Porsche 911">Porsche 911</a> sports car, which has used flat-six engines continuously since 1963. Several other car manufacturers, including Subaru, have produced flat-six engines at times. Flat-six engines have also occasionally been used in motorcycles, and commonly in general aviation aircraft, along with the <a href="/wiki/Flat-four_engine" title="Flat-four engine">flat-four engine</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Engine_balance">Engine balance</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flat-six_engine&action=edit&section=1" title="Edit section: Engine balance"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Further information: <a href="/wiki/Flat_engine" title="Flat engine">Flat engine</a></div> <p>A <a href="/wiki/Boxer_engine" class="mw-redirect" title="Boxer engine">boxer-style</a> flat-six engine is able to have perfect <a href="/wiki/Primary_balance" class="mw-redirect" title="Primary balance">primary</a> and <a href="/wiki/Secondary_balance" class="mw-redirect" title="Secondary balance">secondary balance</a>. As in other six-cylinder engines, the overlapping of the power strokes of the different cylinders (with a firing interval of 120 degrees in a four-stroke engine) reduces the pulsating of the power delivery relative to that of similar engines with fewer cylinders. </p><p>In a <a href="/wiki/Boxer_engine" class="mw-redirect" title="Boxer engine">boxer</a> configuration, a flat-six engine does not have a <a href="/wiki/Couple_(mechanics)" title="Couple (mechanics)">rocking couple</a>. The symmetry of the arrangement, in which one bank of three cylinders is mirrored by the other bank, means that there is no net force from any given mirrored cylinder pair along the axis of movement of the pistons. So not only is there no net primary or secondary reciprocating effect, there is no net turning force - moment - that would try to rotate the engine back and forth about its engine mountings. (The moment is not quite zero in practice because each cylinder pair is offset slightly from the other, or else they would clash at the crankshaft.) In this regard, the six cylinder boxer engine is the same as a flat-four boxer engine, which also does not experience any rocking couple.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>These characteristics result in low vibration for flat-six engines (as in <a href="/wiki/Straight-six_engine" title="Straight-six engine">straight-six engines</a>), especially when compared with the imbalances that are present in <a href="/wiki/V6_engine" title="V6 engine">V6 engines</a> with a 90-degree bank angle. </p> <div class="mw-heading mw-heading2"><h2 id="Use_in_aircraft">Use in aircraft</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flat-six_engine&action=edit&section=2" title="Edit section: Use in aircraft"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:FranklinO335engine1.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/d/db/FranklinO335engine1.JPG/220px-FranklinO335engine1.JPG" decoding="async" width="220" height="233" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/d/db/FranklinO335engine1.JPG/330px-FranklinO335engine1.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/d/db/FranklinO335engine1.JPG/440px-FranklinO335engine1.JPG 2x" data-file-width="1897" data-file-height="2009" /></a><figcaption>1945–1975 <a href="/wiki/Franklin_O-335" title="Franklin O-335">Franklin O-335</a> air-cooled aircraft engine</figcaption></figure> <p>Early flat-six engines include the <a href="/wiki/Franklin_O-265" title="Franklin O-265">Franklin O-265</a> which began production in 1940, and the <a href="/wiki/Lycoming_O-435" title="Lycoming O-435">Lycoming O-435</a> which began production in 1942. Several manufacturers use the letter <i>O</i> in their model codes for flat-layout engines as a designation for “opposed” cylinder layouts. The <a href="/wiki/Franklin_O-335" title="Franklin O-335">Franklin O-335</a> was used in the <a href="/wiki/Bell_47" title="Bell 47">Bell 47</a> light helicopter. </p><p>Flat engines largely replaced the historically more popular radial engines in small aircraft after World War II because they were less expensive to manufacture. The smaller frontal area compared with a radial engine also results in less drag. </p><p>Some aircraft have used flat-six engines originally designed for cars. The <a href="/wiki/Porsche_PFM_3200" title="Porsche PFM 3200">Porsche PFM 3200</a> engine, produced from 1985 to 1991, was based on the engine used in the Porsche 911 sports car. Several examples of the <a href="/wiki/Pietenpol_Air_Camper" title="Pietenpol Air Camper">Pietenpol Air Camper</a> homebuilt monoplane aircraft have used the air-cooled engine from the <a href="/wiki/Chevrolet_Corvair" title="Chevrolet Corvair">Chevrolet Corvair</a> compact car.<sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> Compared with the engines used in cars, flat-six engines used by helicopters have large displacements and are low revving, producing more torque and less power.<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>A notable recent flat-six aero-engine is the 4-litre <a href="/wiki/Flathead_engine" title="Flathead engine">side-valve</a> <a href="/wiki/Belgium" title="Belgium">Belgian</a> <a href="/wiki/D-Motor_LF39" title="D-Motor LF39">D-Motor LF39</a>, a modular variant of the 2.7-litre <a href="/wiki/Flat-four_engine" title="Flat-four engine">flat-four</a> <a href="/wiki/D-Motor_LF26" title="D-Motor LF26">D-Motor LF26</a>. Although the side-valve format has long been abandoned for most automotive applications because its combustion chamber is a bar to high engine <a href="/wiki/Revolution_per_minute" class="mw-redirect" title="Revolution per minute">rpm</a>, the massively over-square (1.295:1) D-Motor is a very simple, low-revving, compact, reliable lightweight aero-engine (without the heavy (and bulky) complication of <a href="/wiki/Overhead_valve_engine" title="Overhead valve engine">ohv</a> valve-gear).<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Use_in_automobiles">Use in automobiles</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flat-six_engine&action=edit&section=3" title="Edit section: Use in automobiles"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Porsche">Porsche</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flat-six_engine&action=edit&section=4" title="Edit section: Porsche"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236090951"><div role="note" class="hatnote navigation-not-searchable">Further information: <a href="/wiki/Porsche_flat-six_engine" title="Porsche flat-six engine">Porsche flat-six engine</a></div> <figure class="mw-default-size mw-halign-left" typeof="mw:File/Thumb"><a href="/wiki/File:Porsche_911_2.0_004.JPG" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Porsche_911_2.0_004.JPG/220px-Porsche_911_2.0_004.JPG" decoding="async" width="220" height="146" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Porsche_911_2.0_004.JPG/330px-Porsche_911_2.0_004.JPG 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/5c/Porsche_911_2.0_004.JPG/440px-Porsche_911_2.0_004.JPG 2x" data-file-width="1280" data-file-height="850" /></a><figcaption>1966 <a href="/wiki/Porsche_911_(classic)" title="Porsche 911 (classic)">Porsche 911</a> </figcaption></figure> <style data-mw-deduplicate="TemplateStyles:r1235681985">.mw-parser-output .side-box{margin:4px 0;box-sizing:border-box;border:1px solid #aaa;font-size:88%;line-height:1.25em;background-color:var(--background-color-interactive-subtle,#f8f9fa);display:flow-root}.mw-parser-output .side-box-abovebelow,.mw-parser-output .side-box-text{padding:0.25em 0.9em}.mw-parser-output .side-box-image{padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .side-box-imageright{padding:2px 0.9em 2px 0;text-align:center}@media(min-width:500px){.mw-parser-output .side-box-flex{display:flex;align-items:center}.mw-parser-output .side-box-text{flex:1;min-width:0}}@media(min-width:720px){.mw-parser-output .side-box{width:238px}.mw-parser-output .side-box-right{clear:right;float:right;margin-left:1em}.mw-parser-output .side-box-left{margin-right:1em}}</style><style data-mw-deduplicate="TemplateStyles:r1096940132">.mw-parser-output .listen .side-box-text{line-height:1.1em}.mw-parser-output .listen-plain{border:none;background:transparent}.mw-parser-output .listen-embedded{width:100%;margin:0;border-width:1px 0 0 0;background:transparent}.mw-parser-output .listen-header{padding:2px}.mw-parser-output .listen-embedded .listen-header{padding:2px 0}.mw-parser-output .listen-file-header{padding:4px 0}.mw-parser-output .listen .description{padding-top:2px}.mw-parser-output .listen .mw-tmh-player{max-width:100%}@media(max-width:719px){.mw-parser-output .listen{clear:both}}@media(min-width:720px){.mw-parser-output .listen:not(.listen-noimage){width:320px}.mw-parser-output .listen-left{overflow:visible;float:left}.mw-parser-output .listen-center{float:none;margin-left:auto;margin-right:auto}}</style><div class="side-box side-box-right listen noprint"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style> <div class="side-box-flex"> <div class="side-box-image"><figure class="mw-halign-center" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/8/87/Gnome-mime-sound-openclipart.svg/50px-Gnome-mime-sound-openclipart.svg.png" decoding="async" width="50" height="50" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/87/Gnome-mime-sound-openclipart.svg/75px-Gnome-mime-sound-openclipart.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/8/87/Gnome-mime-sound-openclipart.svg/100px-Gnome-mime-sound-openclipart.svg.png 2x" data-file-width="160" data-file-height="160" /></span><figcaption></figcaption></figure></div> <div class="side-box-text plainlist"><div class="haudio"> <div class="listen-file-header"><a href="/wiki/File:Porsche_911R_(1967).ogg" title="File:Porsche 911R (1967).ogg">1967 Porsche 911R</a></div> <div><span typeof="mw:File"><span><audio id="mwe_player_0" controls="" preload="none" data-mw-tmh="" class="mw-file-element" width="232" style="width:232px;" data-durationhint="22" data-mwtitle="Porsche_911R_(1967).ogg" data-mwprovider="wikimediacommons"><source src="//upload.wikimedia.org/wikipedia/commons/1/17/Porsche_911R_%281967%29.ogg" type="audio/ogg; codecs="vorbis"" data-width="0" data-height="0" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/1/17/Porsche_911R_%281967%29.ogg/Porsche_911R_%281967%29.ogg.mp3" type="audio/mpeg" data-transcodekey="mp3" data-width="0" data-height="0" /></audio></span></span></div> <div class="description"></div></div><hr /><div class="haudio"> <div class="listen-file-header"><a href="/wiki/File:2006_Porsche_Cayman_S_engine_sound.wav" title="File:2006 Porsche Cayman S engine sound.wav">2006 Porsche Cayman S</a></div> <div><span typeof="mw:File"><span><audio id="mwe_player_1" controls="" preload="none" data-mw-tmh="" class="mw-file-element" width="232" style="width:232px;" data-durationhint="34" data-mwtitle="2006_Porsche_Cayman_S_engine_sound.wav" data-mwprovider="wikimediacommons"><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/6/68/2006_Porsche_Cayman_S_engine_sound.wav/2006_Porsche_Cayman_S_engine_sound.wav.ogg" type="audio/ogg; codecs="vorbis"" data-transcodekey="ogg" data-width="0" data-height="0" /><source src="//upload.wikimedia.org/wikipedia/commons/transcoded/6/68/2006_Porsche_Cayman_S_engine_sound.wav/2006_Porsche_Cayman_S_engine_sound.wav.mp3" type="audio/mpeg" data-transcodekey="mp3" data-width="0" data-height="0" /><source src="//upload.wikimedia.org/wikipedia/commons/6/68/2006_Porsche_Cayman_S_engine_sound.wav" type="audio/wav" data-width="0" data-height="0" /></audio></span></span></div> <div class="description"></div></div></div></div> <div class="side-box-abovebelow"><hr /><i class="selfreference">Problems playing these files? See <a href="/wiki/Help:Media" title="Help:Media">media help</a>.</i></div> </div> <p>The flat-six engine is often associated with the <a href="/wiki/Porsche_911" title="Porsche 911">Porsche 911</a>, a rear-engined sports car which has used flat-six engines exclusively since 1963. The engines were <a href="/wiki/Air-cooled_engine" title="Air-cooled engine">air-cooled</a> until 1999, when Porsche started using <a href="/wiki/Water_cooling_(engines)" class="mw-redirect" title="Water cooling (engines)">water-cooled engines</a>.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p><p>Other Porsche models that use flat-six engines are the 1970–1972 <a href="/wiki/Porsche_914" title="Porsche 914">Porsche 914/6</a> (<a href="/wiki/Mid-engine" class="mw-redirect" title="Mid-engine">mid-engine</a>), the 1986–1993 <a href="/wiki/Porsche_959" title="Porsche 959">Porsche 959</a> (<a href="/wiki/Rear_engine" class="mw-redirect" title="Rear engine">rear-engine</a>), and the 1996–2021 <a href="/wiki/Porsche_Boxster/Cayman" class="mw-redirect" title="Porsche Boxster/Cayman">Porsche Boxster/Cayman</a> (mid-engine). </p> <div style="clear:both;" class=""></div> <div class="mw-heading mw-heading3"><h3 id="Other_manufacturers">Other manufacturers</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flat-six_engine&action=edit&section=5" title="Edit section: Other manufacturers"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1237032888/mw-parser-output/.tmulti">.mw-parser-output .tmulti .multiimageinner{display:flex;flex-direction:column}.mw-parser-output .tmulti .trow{display:flex;flex-direction:row;clear:left;flex-wrap:wrap;width:100%;box-sizing:border-box}.mw-parser-output .tmulti .tsingle{margin:1px;float:left}.mw-parser-output .tmulti .theader{clear:both;font-weight:bold;text-align:center;align-self:center;background-color:transparent;width:100%}.mw-parser-output .tmulti .thumbcaption{background-color:transparent}.mw-parser-output .tmulti .text-align-left{text-align:left}.mw-parser-output .tmulti .text-align-right{text-align:right}.mw-parser-output .tmulti .text-align-center{text-align:center}@media all and (max-width:720px){.mw-parser-output .tmulti .thumbinner{width:100%!important;box-sizing:border-box;max-width:none!important;align-items:center}.mw-parser-output .tmulti .trow{justify-content:center}.mw-parser-output .tmulti .tsingle{float:none!important;max-width:100%!important;box-sizing:border-box;text-align:center}.mw-parser-output .tmulti .tsingle .thumbcaption{text-align:left}.mw-parser-output .tmulti .trow>.thumbcaption{text-align:center}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmulti .multiimageinner img{background-color:white}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmulti .multiimageinner img{background-color:white}}</style><div class="thumb tmulti tright"><div class="thumbinner multiimageinner" style="width:224px;max-width:224px"><div class="trow"><div class="tsingle" style="width:222px;max-width:222px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:The_Wilson-Pilcher_Flat-Six_engine.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/4/47/The_Wilson-Pilcher_Flat-Six_engine.jpg/220px-The_Wilson-Pilcher_Flat-Six_engine.jpg" decoding="async" width="220" height="190" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/4/47/The_Wilson-Pilcher_Flat-Six_engine.jpg/330px-The_Wilson-Pilcher_Flat-Six_engine.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/4/47/The_Wilson-Pilcher_Flat-Six_engine.jpg/440px-The_Wilson-Pilcher_Flat-Six_engine.jpg 2x" data-file-width="773" data-file-height="668" /></a></span></div><div class="thumbcaption">1904 <a href="/wiki/Wilson-Pilcher" title="Wilson-Pilcher">Wilson-Pilcher</a> engine</div></div></div><div class="trow"><div class="tsingle" style="width:222px;max-width:222px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:SUBARU_EZ36_001.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/SUBARU_EZ36_001.jpg/220px-SUBARU_EZ36_001.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/c/c1/SUBARU_EZ36_001.jpg/330px-SUBARU_EZ36_001.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/c/c1/SUBARU_EZ36_001.jpg/440px-SUBARU_EZ36_001.jpg 2x" data-file-width="1600" data-file-height="1200" /></a></span></div><div class="thumbcaption">2007–2019 <a href="/wiki/Subaru_six-cylinder_engines#EZ36" title="Subaru six-cylinder engines">Subaru EZ36</a> engine</div></div></div></div></div> <p>The first car to use a flat-six engine was the 1904–1907 <i><a href="/wiki/Wilson-Pilcher" title="Wilson-Pilcher">Wilson-Pilcher</a> 18/24 HP</i>,<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> which used an engine based on a flat-four engine with two cylinders added. The Wilson-Pilcher was a front-engined car with the crankshaft in-line with the chassis and the cylinders between the chassis rails. Reports on this car quote it as being "remarkably silent and smooth running" and "almost total absence of vibration".<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> </p><p>Two American manufacturers briefly produced cars with flat-six engines—the 1948 <a href="/wiki/Tucker_48" title="Tucker 48">Tucker 48</a> (water-cooled, based on the Franklin O-335) and the 1960–1969 <a href="/wiki/Chevrolet_Corvair" title="Chevrolet Corvair">Chevrolet Corvair</a> (air-cooled).<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup> Both are rear-engined cars with rear-wheel drive. Chevrolet produced over 1.8 million Corvairs of various types and utilized a turbocharger on some models; one of the first uses of a turbocharger on a mass-produced automobile. </p><p>Japanese manufacturer Subaru produced water-cooled flat-6 engines from 1988–1996 and 2000–2019.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> Their first flat-6 engine, the <a href="/wiki/Subaru_six-cylinder_engines#ER27" title="Subaru six-cylinder engines">Subaru ER27</a>, was added to the model range of the <a href="/wiki/Subaru_XT" title="Subaru XT">Subaru XT</a> coupe. In 1991, the <a href="/wiki/Subaru_six-cylinder_engines#EG33" title="Subaru six-cylinder engines">Subaru EG33</a> engine was used in the <a href="/wiki/Subaru_Alcyone_SVX" title="Subaru Alcyone SVX">Subaru Alcyone SVX</a>, the replacement for the Subaru XT.<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> Following a hiatus of flat-6 engine production for four years, the <a href="/wiki/Subaru_six-cylinder_engines#EZ30_and_EZ36" title="Subaru six-cylinder engines">Subaru EZ30</a> engine was introduced in the 2000 <a href="/wiki/Subaru_Legacy_(third_generation)" title="Subaru Legacy (third generation)">Subaru Legacy/Outback</a>. The <a href="/wiki/Subaru_EZ36" class="mw-redirect" title="Subaru EZ36">Subaru EZ36</a> engine was introduced in 2007 and was produced until 2019. All engines were used in front-engine cars with all-wheel drive, plus the XT and Alcyone SVX were also available with front-wheel drive. </p> <div style="clear:right;" class=""></div> <div class="mw-heading mw-heading2"><h2 id="Use_in_motorcycles">Use in motorcycles</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flat-six_engine&action=edit&section=6" title="Edit section: Use in motorcycles"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Flat.six.honda.valkyrie.arp.750pix.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Flat.six.honda.valkyrie.arp.750pix.jpg/220px-Flat.six.honda.valkyrie.arp.750pix.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Flat.six.honda.valkyrie.arp.750pix.jpg/330px-Flat.six.honda.valkyrie.arp.750pix.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Flat.six.honda.valkyrie.arp.750pix.jpg/440px-Flat.six.honda.valkyrie.arp.750pix.jpg 2x" data-file-width="750" data-file-height="561" /></a><figcaption>1997–2004 <a href="/wiki/Honda_Valkyrie" title="Honda Valkyrie">Honda Valkyrie</a> engine</figcaption></figure> <p>Most motorcycles use engines with four or fewer cylinders, however the <a href="/wiki/Honda_Gold_Wing" title="Honda Gold Wing">Honda Gold Wing</a> touring motorcycle has used a water-cooled flat-six engine since 1988.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> Initially, the engine had a displacement of 1.5 L (92 cu in), until it was enlarged to 1.8 L (110 cu in) in 2001.<sup id="cite_ref-Mitchel_13-0" class="reference"><a href="#cite_note-Mitchel-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page: 208">: 208 </span></sup> </p><p>The <a href="/wiki/Honda_Valkyrie" title="Honda Valkyrie">Honda Valkyrie</a> F6C (1997–2003) was a cruiser based on the GL1500 Gold Wing.<sup id="cite_ref-Mitchel_13-1" class="reference"><a href="#cite_note-Mitchel-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Pages: 198, 218">: 198, 218 </span></sup> The limited edition 2004 Valkyrie Rune was based on the GL1800.<sup id="cite_ref-Mitchel_13-2" class="reference"><a href="#cite_note-Mitchel-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Pages: 218, 220">: 218, 220 </span></sup> </p> <div style="clear:both;" class=""></div> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flat-six_engine&action=edit&section=7" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Inline-six_engine" class="mw-redirect" title="Inline-six engine">Inline-six engine</a></li> <li><a href="/wiki/V6_engine" title="V6 engine">V6 engine</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Flat-six_engine&action=edit&section=8" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width" style="column-width: 30em;"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFNunney2007" class="citation book cs1">Nunney, M J (2007). <a rel="nofollow" class="external text" href="https://books.google.com/books?id=xLxySLNAe3YC&pg=PA13"><i>Light and Heavy Vehicle Technology</i></a>. Butterworth-Heinemann. p. 13. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-7506-8037-0" title="Special:BookSources/978-0-7506-8037-0"><bdi>978-0-7506-8037-0</bdi></a><span class="reference-accessdate">. Retrieved <span class="nowrap">24 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Light+and+Heavy+Vehicle+Technology&rft.pages=13&rft.pub=Butterworth-Heinemann&rft.date=2007&rft.isbn=978-0-7506-8037-0&rft.aulast=Nunney&rft.aufirst=M+J&rft_id=https%3A%2F%2Fbooks.google.com%2Fbooks%3Fid%3DxLxySLNAe3YC%26pg%3DPA13&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.caranddriver.com/features/a15126436/the-physics-of-engine-cylinder-bank-angles-feature/">"The Physics of: Engine Cylinder-Bank Angles"</a>. <i>www.caranddriver.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">9 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.caranddriver.com&rft.atitle=The+Physics+of%3A+Engine+Cylinder-Bank+Angles&rft_id=https%3A%2F%2Fwww.caranddriver.com%2Ffeatures%2Fa15126436%2Fthe-physics-of-engine-cylinder-bank-angles-feature%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20170423060658/http://community.pressenter.net/~apietenp/BHPietenpolAndSonsAirCamperAircraftHistoryofPietenpolAirCamper.html">"Pietenpol Official Pietenpol Air Camper Family Website"</a>. <i>community.pressenter.net</i>. Pietenpol Aircraft Company. Archived from <a rel="nofollow" class="external text" href="http://community.pressenter.net/~apietenp/BHPietenpolAndSonsAirCamperAircraftHistoryofPietenpolAirCamper.html">the original</a> on April 23, 2017<span class="reference-accessdate">. Retrieved <span class="nowrap">May 6,</span> 2017</span>. <q>As the years passed, Bernard Pietenpol taught himself how to repair televisions and radios. By 1960, Chevrolet introduced the six cylinder air-cooled Chevrolet Corvair. This would be the last engine Bernard would experiment with in powering his Air Camper. In 1966 Bernard completed his first Corvair powered Air Camper, then another in 1970 which was dubbed "the Last Original".</q></cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=community.pressenter.net&rft.atitle=Pietenpol+Official+Pietenpol+Air+Camper+Family+Website&rft_id=http%3A%2F%2Fcommunity.pressenter.net%2F~apietenp%2FBHPietenpolAndSonsAirCamperAircraftHistoryofPietenpolAirCamper.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20190919085444/http://hieldsaviation.co.uk/the-lycoming-o-540-engine-and-why-we-use-it/">"The Lycoming O-540 Engine and Why We Use It"</a>. <i>www.hieldsaviation.co.uk</i>. 18 November 2015. Archived from <a rel="nofollow" class="external text" href="http://hieldsaviation.co.uk/the-lycoming-o-540-engine-and-why-we-use-it/">the original</a> on 19 September 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">10 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.hieldsaviation.co.uk&rft.atitle=The+Lycoming+O-540+Engine+and+Why+We+Use+It&rft.date=2015-11-18&rft_id=http%3A%2F%2Fhieldsaviation.co.uk%2Fthe-lycoming-o-540-engine-and-why-we-use-it%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text">Note: A low-revving engine is eminently suitable to drive a propeller, which is typically most effective at about 2,000 rpm. If a valve in a side-valve engine should stick open, it cannot hit the piston and cause engine failure; the engine will continue with just that cylinder inoperative. This is an important safety feature for aero-engines.</span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.caranddriver.com/news/a15366914/flat-sixy-the-evolution-of-porsche-911-engine-size-technology-and-output-in-the-u-s/">"Flat Sixy: The Evolution of Porsche 911 Engine Size, Technology, and Output in the U.S."</a> <i>www.caranddriver.com</i>. 13 December 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">21 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.caranddriver.com&rft.atitle=Flat+Sixy%3A+The+Evolution+of+Porsche+911+Engine+Size%2C+Technology%2C+and+Output+in+the+U.S.&rft.date=2013-12-13&rft_id=https%3A%2F%2Fwww.caranddriver.com%2Fnews%2Fa15366914%2Fflat-sixy-the-evolution-of-porsche-911-engine-size-technology-and-output-in-the-u-s%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.carthrottle.com/post/7-flat-six-powered-vehicles-that-arent-porsches/">"7 Flat-Six-Powered Vehicles That Aren't Porsches"</a>. <i>www.carthrottle.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">21 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.carthrottle.com&rft.atitle=7+Flat-Six-Powered+Vehicles+That+Aren%27t+Porsches&rft_id=https%3A%2F%2Fwww.carthrottle.com%2Fpost%2F7-flat-six-powered-vehicles-that-arent-porsches%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text">"The Wilson-Pilcher Petrol Cars", The Automotor Journal, April 16th, 1904, pp. 463-468</span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20140622041530/http://www.corvair.org/index.php?option=com_k2&view=item&layout=item&id=6&Itemid=648">"Corvair History"</a>. <i>www.corvair.org</i>. Archived from <a rel="nofollow" class="external text" href="http://www.corvair.org/index.php?option=com_k2&view=item&layout=item&id=6&Itemid=648">the original</a> on 22 June 2014.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.corvair.org&rft.atitle=Corvair+History&rft_id=http%3A%2F%2Fwww.corvair.org%2Findex.php%3Foption%3Dcom_k2%26view%3Ditem%26layout%3Ditem%26id%3D6%26Itemid%3D648&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://web.archive.org/web/20190921022942/http://www.dailyturismo.com/2018/06/flat-6-club-1993-subaru-impreza-w.html">"Flat-6 Club: 1993 Subaru Impreza w/ Legacy 6-Cyl"</a>. <i>www.dailyturismo.com</i>. Archived from <a rel="nofollow" class="external text" href="http://www.dailyturismo.com/2018/06/flat-6-club-1993-subaru-impreza-w.html">the original</a> on 21 September 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">21 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.dailyturismo.com&rft.atitle=Flat-6+Club%3A+1993+Subaru+Impreza+w%2F+Legacy+6-Cyl&rft_id=http%3A%2F%2Fwww.dailyturismo.com%2F2018%2F06%2Fflat-6-club-1993-subaru-impreza-w.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.cars101.com/subaru/subaru_history.html">"Subaru history in the USA: the models, the changes"</a>. <i>www.cars101.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">23 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.cars101.com&rft.atitle=Subaru+history+in+the+USA%3A+the+models%2C+the+changes&rft_id=http%3A%2F%2Fwww.cars101.com%2Fsubaru%2Fsubaru_history.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://powersports.honda.com/street/touring">"Touring"</a>. <i>www.honda.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">23 September</span> 2019</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.honda.com&rft.atitle=Touring&rft_id=https%3A%2F%2Fpowersports.honda.com%2Fstreet%2Ftouring&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> <li id="cite_note-Mitchel-13"><span class="mw-cite-backlink">^ <a href="#cite_ref-Mitchel_13-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Mitchel_13-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Mitchel_13-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMitchel2005" class="citation book cs1">Mitchel, Doug (2005). <i>Honda Motorcycles: Everything You Need to Know About Every Honda Motorcycle Ever Built</i>. Krause Publications. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/9780873499668" title="Special:BookSources/9780873499668"><bdi>9780873499668</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Honda+Motorcycles%3A+Everything+You+Need+to+Know+About+Every+Honda+Motorcycle+Ever+Built&rft.pub=Krause+Publications&rft.date=2005&rft.isbn=9780873499668&rft.aulast=Mitchel&rft.aufirst=Doug&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFlat-six+engine" class="Z3988"></span></span> </li> </ol></div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline 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ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Piston_engine_configurations" title="Template:Piston engine configurations"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Piston_engine_configurations" title="Template talk:Piston engine configurations"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Piston_engine_configurations" title="Special:EditPage/Template:Piston engine configurations"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Engine_configurations_for_piston_engines" style="font-size:114%;margin:0 4em"><a href="/wiki/Engine_configuration" title="Engine configuration">Engine configurations</a> for <a href="/wiki/Piston_engine" class="mw-redirect" title="Piston engine">piston engines</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Type</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Newcomen_atmospheric_engine" title="Newcomen atmospheric engine">Atmospheric</a></li> <li><a href="/wiki/Axial_engine" title="Axial engine">Axial</a></li> <li><a href="/wiki/Beam_engine" title="Beam engine">Beam</a> <ul><li><a href="/wiki/Cornish_steam_engine" class="mw-redirect" title="Cornish steam engine">Cornish</a></li> <li><a href="/wiki/Rotative_beam_engine" class="mw-redirect" title="Rotative beam engine">Rotative</a></li></ul></li> <li><a href="/wiki/Bourke_engine" title="Bourke engine">Bourke</a></li> <li><a href="/wiki/Cam_engine" title="Cam engine">Cam engine</a></li> <li><a href="/wiki/Camless_piston_engine" title="Camless piston engine">Camless</a></li> <li><a href="/wiki/Compound_steam_engine" title="Compound steam engine">Compound</a></li> <li><a href="/wiki/Double-acting_cylinder" class="mw-redirect" title="Double-acting cylinder">Double-acting cylinder</a></li> <li><a href="/wiki/Flathead_engine" title="Flathead engine">Flathead</a></li> <li><a href="/wiki/Free-piston_engine" title="Free-piston engine">Free-piston</a> <ul><li><a href="/wiki/Stelzer_engine" title="Stelzer engine">Stelzer</a></li></ul></li> <li><a href="/wiki/Hemi_engine" class="mw-redirect" title="Hemi engine">Hemi</a></li> <li><a href="/wiki/Heron_cylinder_head" title="Heron cylinder head">Heron head</a></li> <li><a href="/wiki/IOE_engine" title="IOE engine">Intake over exhaust</a></li> <li><a href="/wiki/Oscillating_cylinder_steam_engine" title="Oscillating cylinder steam engine">Oscillating cylinder</a></li> <li><a href="/wiki/Opposed-piston_engine" title="Opposed-piston engine">Opposed-piston</a></li> <li><a href="/wiki/Overhead_camshaft_engine" title="Overhead camshaft engine">Overhead camshaft</a></li> <li><a href="/wiki/Overhead_valve_engine" title="Overhead valve engine">Overhead valve</a></li> <li><a href="/wiki/Pent-roof_combustion_chamber" title="Pent-roof combustion chamber">Pentroof</a></li> <li><a href="/wiki/Rotary_engine" title="Rotary engine">Rotary</a></li> <li><a href="/wiki/Single-acting_cylinder" class="mw-redirect" title="Single-acting cylinder">Single-acting cylinder</a></li> <li><a href="/wiki/Split_cycle_engine" class="mw-redirect" title="Split cycle engine">Split cycle</a></li> <li><a href="/wiki/Swing-piston_engine" title="Swing-piston engine">Swing-piston</a></li> <li><a href="/wiki/Uniflow_steam_engine" title="Uniflow steam engine">Uniflow</a></li> <li><a href="/wiki/Watt_steam_engine" title="Watt steam engine">Watt</a></li> <li><a href="/wiki/Chrysler_wedge_engine" class="mw-redirect" title="Chrysler wedge engine">Wedge</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Stroke_(engine)" title="Stroke (engine)">Stroke cycles</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Two-stroke_engine" title="Two-stroke engine">Two-stroke</a></li> <li><a href="/wiki/Four-stroke_engine" title="Four-stroke engine">Four-stroke</a></li> <li><a href="/wiki/Five-stroke_engine" title="Five-stroke engine">Five-stroke</a></li> <li><a href="/wiki/Six-stroke_engine" title="Six-stroke engine">Six-stroke</a></li> <li><a href="/wiki/Two-_and_four-stroke_engines" title="Two- and four-stroke engines">Two-and four-stroke</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Engine_configuration" title="Engine configuration">Cylinder layouts</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/Straight_engine" title="Straight engine">Inline / straight</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Single-cylinder_engine" title="Single-cylinder engine">I1</a></li> <li><a href="/wiki/Straight-twin_engine" title="Straight-twin engine">I2</a></li> <li><a href="/wiki/Straight-three_engine" title="Straight-three engine">I3</a></li> <li><a href="/wiki/Straight-four_engine" title="Straight-four engine">I4</a></li> <li><a href="/wiki/Straight-five_engine" title="Straight-five engine">I5</a></li> <li><a href="/wiki/Straight-six_engine" title="Straight-six engine">I6</a></li> <li><a href="/wiki/Straight-seven_engine" title="Straight-seven engine">I7</a></li> <li><a href="/wiki/Straight-eight_engine" title="Straight-eight engine">I8</a></li> <li><a href="/wiki/Straight-nine_engine" title="Straight-nine engine">I9</a></li> <li><a href="/wiki/Straight-twelve_engine" title="Straight-twelve engine">I12</a></li> <li><a href="/wiki/Straight-fourteen_engine" title="Straight-fourteen engine">I14</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/Flat_engine" title="Flat engine">Flat / boxer</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Flat-twin_engine" title="Flat-twin engine">F2</a></li> <li><a href="/wiki/Flat-four_engine" title="Flat-four engine">F4</a></li> <li><a class="mw-selflink selflink">F6</a></li> <li><a href="/wiki/Flat-eight_engine" title="Flat-eight engine">F8</a></li> <li><a href="/wiki/Flat-ten_engine" title="Flat-ten engine">F10</a></li> <li><a href="/wiki/Flat-twelve_engine" title="Flat-twelve engine">F12</a></li> <li><a href="/wiki/Flat-sixteen_engine" title="Flat-sixteen engine">F16</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/V_engine" title="V engine">V / Vee</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/V-twin_engine" title="V-twin engine">V2</a></li> <li><a href="/wiki/V3_engine" title="V3 engine">V3</a></li> <li><a href="/wiki/V4_engine" title="V4 engine">V4</a></li> <li><a href="/wiki/V5_engine" title="V5 engine">V5</a> <ul><li><a href="/wiki/VR5_engine" title="VR5 engine">VR5</a></li></ul></li> <li><a href="/wiki/V6_engine" title="V6 engine">V6</a> <ul><li><a href="/wiki/VR6_engine" title="VR6 engine">VR6</a></li></ul></li> <li><a href="/wiki/V8_engine" title="V8 engine">V8</a></li> <li><a href="/wiki/V10_engine" title="V10 engine">V10</a></li> <li><a href="/wiki/V12_engine" title="V12 engine">V12</a></li> <li><a href="/wiki/V14_engine" title="V14 engine">V14</a></li> <li><a href="/wiki/V16_engine" title="V16 engine">V16</a></li> <li><a href="/wiki/V18_engine" title="V18 engine">V18</a></li> <li><a href="/wiki/V20_engine" title="V20 engine">V20</a></li> <li><a href="/wiki/V24_engine" title="V24 engine">V24</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em"><a href="/wiki/W_engine" title="W engine">W</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/W_engine#W3_engines" title="W engine">W3</a></li> <li><a href="/wiki/W_engine#W6_engines" title="W engine">W6</a></li> <li><a href="/wiki/W8_engine" title="W8 engine">W8</a></li> <li><a href="/wiki/W12_engine" title="W12 engine">W12</a></li> <li><a href="/wiki/W16_engine" title="W16 engine">W16</a></li> <li><a href="/wiki/W18_engine" title="W18 engine">W18</a></li> <li><a href="/wiki/W_engine#W24_engine" title="W engine">W24</a></li> <li><a href="/wiki/W_engine#W30_engine" title="W engine">W30</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:10em">Other</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Napier_Deltic" title="Napier Deltic">Deltic</a></li> <li><a href="/wiki/H_engine" title="H engine">H</a></li> <li><a href="/wiki/Radial_engine" title="Radial engine">Radial</a></li> <li><a href="/wiki/Split-single_engine" title="Split-single engine">Split-single</a></li> <li><a href="/wiki/U_engine" title="U engine">U</a></li> <li><a href="/wiki/X_engine" title="X engine">X</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1&useformat=desktop" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=Flat-six_engine&oldid=1240686222">https://en.wikipedia.org/w/index.php?title=Flat-six_engine&oldid=1240686222</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" 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