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href="https://de.wikipedia.org/wiki/Turbolader#Umluftventil" title="Turbolader – German" lang="de" hreflang="de" data-title="Turbolader" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/V%C3%A1lvula_de_descarga" title="Válvula de descarga – Spanish" lang="es" hreflang="es" data-title="Válvula de descarga" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Soupape_de_d%C3%A9charge" title="Soupape de décharge – French" lang="fr" hreflang="fr" data-title="Soupape de décharge" data-language-autonym="Français" data-language-local-name="French" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EB%B8%94%EB%A1%9C%EC%98%A4%ED%94%84_%EB%B0%B8%EB%B8%8C" title="블로오프 밸브 – Korean" lang="ko" hreflang="ko" data-title="블로오프 밸브" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Pop-off_(meccanica)" title="Pop-off (meccanica) – Italian" lang="it" hreflang="it" data-title="Pop-off (meccanica)" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E3%83%96%E3%83%AD%E3%83%BC%E3%82%AA%E3%83%95%E3%83%90%E3%83%AB%E3%83%96" title="ブローオフバルブ – Japanese" lang="ja" hreflang="ja" data-title="ブローオフバルブ" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Dumpventil" title="Dumpventil – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Dumpventil" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Dumpventil" title="Dumpventil – Norwegian Nynorsk" lang="nn" hreflang="nn" data-title="Dumpventil" data-language-autonym="Norsk nynorsk" data-language-local-name="Norwegian Nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Zaw%C3%B3r_upustowy" title="Zawór upustowy – Polish" lang="pl" hreflang="pl" data-title="Zawór upustowy" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%9F%D0%B5%D1%80%D0%B5%D0%BF%D1%83%D1%81%D0%BA%D0%BD%D0%BE%D0%B9_%D0%BA%D0%BB%D0%B0%D0%BF%D0%B0%D0%BD" title="Перепускной клапан – Russian" lang="ru" hreflang="ru" data-title="Перепускной клапан" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Blow-off_ventil" title="Blow-off ventil – Slovak" lang="sk" hreflang="sk" data-title="Blow-off ventil" data-language-autonym="Slovenčina" data-language-local-name="Slovak" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Dumpventil" title="Dumpventil – Swedish" lang="sv" 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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:408px;max-width:408px"><div class="trow"><div class="tsingle" style="width:202px;max-width:202px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Throttle_body_openBOV12.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/5/56/Throttle_body_openBOV12.jpg/200px-Throttle_body_openBOV12.jpg" decoding="async" width="200" height="145" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/5/56/Throttle_body_openBOV12.jpg/300px-Throttle_body_openBOV12.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/5/56/Throttle_body_openBOV12.jpg/400px-Throttle_body_openBOV12.jpg 2x" data-file-width="3611" data-file-height="2615" /></a></span></div><div class="thumbcaption">Throttle open, therefore the blowoff valve is shut</div></div><div class="tsingle" style="width:202px;max-width:202px"><div class="thumbimage"><span typeof="mw:File"><a href="/wiki/File:Throttle_body_closedBOV7.jpg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Throttle_body_closedBOV7.jpg/200px-Throttle_body_closedBOV7.jpg" decoding="async" width="200" height="139" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/63/Throttle_body_closedBOV7.jpg/300px-Throttle_body_closedBOV7.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/63/Throttle_body_closedBOV7.jpg/400px-Throttle_body_closedBOV7.jpg 2x" data-file-width="3797" data-file-height="2638" /></a></span></div><div class="thumbcaption">Throttle closed, air pushes the blowoff valve open (upwards)</div></div></div></div></div> <p>A <b>blowoff valve</b> (also called <b>dump valve</b> or <b>compressor bypass valve</b>) is a pressure release system present in most petrol <a href="/wiki/Turbocharger" title="Turbocharger">turbocharged</a> engines. Blowoff valves are used to reduce pressure in the intake system as the throttle is closed, thus preventing <a href="/wiki/Compressor_stall" title="Compressor stall">compressor surge</a>.<sup id="cite_ref-GFB_1-0" class="reference"><a href="#cite_note-GFB-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Design">Design</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Blowoff_valve&action=edit&section=1" title="Edit section: Design"><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:Dahlb%C3%A4ck_valve.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Dahlb%C3%A4ck_valve.jpg/220px-Dahlb%C3%A4ck_valve.jpg" decoding="async" width="220" height="165" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Dahlb%C3%A4ck_valve.jpg/330px-Dahlb%C3%A4ck_valve.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/f/f2/Dahlb%C3%A4ck_valve.jpg/440px-Dahlb%C3%A4ck_valve.jpg 2x" data-file-width="4000" data-file-height="3000" /></a><figcaption>A piston-type blowoff valve; this example releases air into the intake manifold (via the side hose on the left, the small hose on the top provides a reference pressure for the blowoff valve from the inlet manifold).</figcaption></figure> <p>A key function of blowoff valves is to prevent <a href="/wiki/Compressor_stall" title="Compressor stall">compressor surge</a>, a phenomenon that would otherwise occur as the throttle is closed in a turbocharged engine. If the turbocharger's compressor wheel is spinning at high speed when the <a href="/wiki/Throttle" title="Throttle">throttle</a> is suddenly closed (such as during a gear change), the flow reduces beyond the surge line of the compressor. At this point the change in pressure across the compressor reduces, leading to a collapse in flow and possibly even flow reversal and a collapse in plenum pressure.<sup id="cite_ref-Garrett_2-0" class="reference"><a href="#cite_note-Garrett-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> As the compressor is still spinning at high speed, once the flow has reduced sufficiently, the change in pressure across the compressor begins to rise and flow is re-established into the plenum.<sup id="cite_ref-GFB_1-1" class="reference"><a href="#cite_note-GFB-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><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> This rapid cycle of pressurisation and depressurisation repeats until the compressor has slowed sufficiently or the throttle is re-opened. The sound produced by compressor surge is called <a href="/wiki/Turbo_flutter" class="mw-redirect" title="Turbo flutter">turbo flutter</a> and the repeated, high speed cycling will cause a cyclic torque on the compressor and may lead to increased stresses on the bearings and compressor impeller.<sup id="cite_ref-Garrett_2-1" class="reference"><a href="#cite_note-Garrett-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>A blowoff valve is designed to release pressure in the intake system when the throttle is closed. A "recirculating" type blowoff valve releases the pressurised air back into the non-pressurized section of the intake (i.e. upstream of the turbocharger), while an "atmospheric venting" type blowoff valve dumps the air directly into the atmosphere. </p> <div class="mw-heading mw-heading2"><h2 id="Operation">Operation</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Blowoff_valve&action=edit&section=2" title="Edit section: Operation"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A vacuum hose connected to the <a href="/wiki/Intake_manifold" class="mw-redirect" title="Intake manifold">intake manifold</a> downstream of the <a href="/wiki/Throttle#Internal_combustion_engines" title="Throttle">throttle</a> provides a reference pressure for the blowoff valve. </p><p>When the throttle is open, the air pressure on both sides of the blowoff valve's piston is equal, therefore the spring holds the valve closed. As the throttle closes, the pressure in the intake manifold drops below the pressure upstream of the throttle, which causes the valve to open. This allows the excess pressure from the turbocharger to be released into either the atmosphere or the intake manifold. </p> <div class="mw-heading mw-heading2"><h2 id="Intake_air_metering">Intake air metering</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Blowoff_valve&action=edit&section=3" title="Edit section: Intake air metering"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In the case where an <a href="/wiki/Mass_flow_sensor" title="Mass flow sensor">airflow sensor</a> is present upstream from the blowoff valve and the blowoff valve vents to atmosphere, the fuel injection system is unaware that some of the intake air has been vented instead of going into the cylinders. This volume of vented air is no longer relevant to the engine, however it is still included in the calculations for the required amount of fuel, which causes excess fuel to be injected and therefore the engine briefly operates with a fuel-rich mixture after each blowoff valve actuation. Effects of this rich running can include fouling the <a href="/wiki/Spark_plug" title="Spark plug">spark plugs</a>, damaging the <a href="/wiki/Catalytic_converter" title="Catalytic converter">catalytic converter</a>, stalling and hesitation when the throttle is opened. </p><p>One method to avoid this issue is by locating the airflow sensor downstream of the blowoff valve (known as a <i>blow-through</i> setup, as opposed to the traditional <i>draw-through</i> setup). By using a blow-through method, the MAF won't be affected by the blowoff valve opening, since the pressure is vented before the air reaches the MAF. </p><p>Other solutions include using a blowoff valve that recirculates the air back into the intake or using a <a href="/wiki/Manifold_absolute_pressure" class="mw-redirect" title="Manifold absolute pressure">manifold absolute pressure</a> sensor (instead of an airflow sensor) to determine the amount of fuel required. </p> <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=Blowoff_valve&action=edit&section=4" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Wastegate" title="Wastegate">Wastegate</a></li> <li><a href="/wiki/Relief_valve" title="Relief valve">Relief valve</a></li> <li><a href="/wiki/Water_hammer" title="Water hammer">Water hammer</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=Blowoff_valve&action=edit&section=5" 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"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-GFB-1"><span class="mw-cite-backlink">^ <a href="#cite_ref-GFB_1-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-GFB_1-1"><sup><i><b>b</b></i></sup></a></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 class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.gfb.com.au/tech/tech-articles/62-all-you-ever-needed-to-know-about-blow-off-valves">"All you ever needed to know about blow-off valves"</a>. <i>www.gfb.com.au</i><span class="reference-accessdate">. Retrieved <span class="nowrap">1 September</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.gfb.com.au&rft.atitle=All+you+ever+needed+to+know+about+blow-off+valves&rft_id=http%3A%2F%2Fwww.gfb.com.au%2Ftech%2Ftech-articles%2F62-all-you-ever-needed-to-know-about-blow-off-valves&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABlowoff+valve" class="Z3988"></span></span> </li> <li id="cite_note-Garrett-2"><span class="mw-cite-backlink">^ <a href="#cite_ref-Garrett_2-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Garrett_2-1"><sup><i><b>b</b></i></sup></a></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.turbobygarrett.com/turbobygarrett/compressor_surge">"What is compressor surge?"</a>. <i>www.turbobygarrett.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">1 September</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.turbobygarrett.com&rft.atitle=What+is+compressor+surge%3F&rft_id=https%3A%2F%2Fwww.turbobygarrett.com%2Fturbobygarrett%2Fcompressor_surge&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABlowoff+valve" 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 id="CITEREFXueWangZhangYang2018" class="citation journal cs1">Xue, Xiang; Wang, Tong; Zhang, Tongtong; Yang, Bo (2018). <a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.cja.2018.04.003">"Mechanism of stall and surge in a centrifugal compressor with a variable vaned diffuser"</a>. <i>Chinese Journal of Aeronautics</i>. <b>31</b> (6): 1222–1231. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.cja.2018.04.003">10.1016/j.cja.2018.04.003</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Chinese+Journal+of+Aeronautics&rft.atitle=Mechanism+of+stall+and+surge+in+a+centrifugal+compressor+with+a+variable+vaned+diffuser&rft.volume=31&rft.issue=6&rft.pages=1222-1231&rft.date=2018&rft_id=info%3Adoi%2F10.1016%2Fj.cja.2018.04.003&rft.aulast=Xue&rft.aufirst=Xiang&rft.au=Wang%2C+Tong&rft.au=Zhang%2C+Tongtong&rft.au=Yang%2C+Bo&rft_id=https%3A%2F%2Fdoi.org%2F10.1016%252Fj.cja.2018.04.003&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABlowoff+valve" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Blowoff_valve&action=edit&section=6" title="Edit section: Further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239549316">.mw-parser-output .refbegin{margin-bottom:0.5em}.mw-parser-output .refbegin-hanging-indents>ul{margin-left:0}.mw-parser-output .refbegin-hanging-indents>ul>li{margin-left:0;padding-left:3.2em;text-indent:-3.2em}.mw-parser-output .refbegin-hanging-indents ul,.mw-parser-output .refbegin-hanging-indents ul li{list-style:none}@media(max-width:720px){.mw-parser-output .refbegin-hanging-indents>ul>li{padding-left:1.6em;text-indent:-1.6em}}.mw-parser-output .refbegin-columns{margin-top:0.3em}.mw-parser-output .refbegin-columns ul{margin-top:0}.mw-parser-output .refbegin-columns li{page-break-inside:avoid;break-inside:avoid-column}@media screen{.mw-parser-output .refbegin{font-size:90%}}</style><div class="refbegin" style=""> <ul><li>Allard, Alan. Turbocharging and Supercharging. Cambridge, England: Patrick Stevens Limited, 1982.</li> <li>Gorla, Rama, and Khan, Aijaz. Turbomachinery Design and Theory. New York, New York: Marcel Dekker, 2003.</li> <li>Society of Automotive Engineers. Turbochargers and Turbocharged Engines. Warrendale, PA, 1979.</li> <li>Watson, N, and Janota, N. Turbocharging the Internal Combustion Engine. London, England: Macmillan Press Ltd, 1982.</li></ul> </div> <p><br /> </p> <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 dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · 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href="/wiki/Crankpin" title="Crankpin">Crankpin</a></li> <li><a href="/wiki/Crankshaft" title="Crankshaft">Crankshaft</a></li> <li><a href="/wiki/Core_plug" title="Core plug">Core plug (freeze plug)</a></li> <li><a href="/wiki/Cylinder_(engine)" title="Cylinder (engine)">Cylinder</a> (<a href="/wiki/Cylinder_bank" class="mw-redirect" title="Cylinder bank">bank</a>, <a href="/wiki/Engine_configuration" title="Engine configuration">layout</a>)</li> <li><a href="/wiki/Engine_displacement" title="Engine displacement">Displacement</a></li> <li><a href="/wiki/Flywheel" title="Flywheel">Flywheel</a></li> <li><a href="/wiki/Firing_order" title="Firing order">Firing order</a></li> <li><a href="/wiki/Stroke_(engine)" title="Stroke (engine)">Stroke</a></li> <li><a href="/wiki/Main_bearing" title="Main bearing">Main bearing</a></li> <li><a href="/wiki/Piston" title="Piston">Piston</a></li> <li><a href="/wiki/Piston_ring" title="Piston ring">Piston ring</a></li> <li><a href="/wiki/Starter_ring_gear" title="Starter ring gear">Starter ring gear</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Valvetrain" title="Valvetrain">Valvetrain</a> and<br /> <a href="/wiki/Cylinder_head" title="Cylinder head">Cylinder head</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/Flathead_engine" title="Flathead engine">Flathead layout</a></li> <li><a href="/wiki/Overhead_camshaft_engine" title="Overhead camshaft engine">Overhead camshaft layout</a></li> <li><a href="/wiki/Overhead_valve_engine" title="Overhead valve engine">Overhead valve (pushrod) layout</a></li></ul> <ul><li><a href="/wiki/Tappet" title="Tappet">Tappet / lifter</a></li> <li><a href="/wiki/Camshaft" title="Camshaft">Camshaft</a></li> <li><a href="/wiki/Chest_(mechanical_engineering)" title="Chest (mechanical engineering)">Chest</a></li> <li><a href="/wiki/Combustion_chamber" title="Combustion chamber">Combustion chamber</a></li> <li><a href="/wiki/Compression_ratio" title="Compression ratio">Compression ratio</a></li> <li><a href="/wiki/Head_gasket" title="Head gasket">Head gasket</a></li> <li><a href="/wiki/Rocker_arm" title="Rocker arm">Rocker arm</a></li> <li><a href="/wiki/Timing_belt_(camshaft)" title="Timing belt (camshaft)">Timing belt</a></li> <li><a href="/wiki/Poppet_valve" title="Poppet valve">Valve</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Forced_induction" title="Forced induction">Forced induction</a></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 class="mw-selflink selflink">Blowoff valve</a></li> <li><a href="/wiki/Boost_controller" title="Boost controller">Boost controller</a></li> <li><a href="/wiki/Intercooler" title="Intercooler">Intercooler</a></li> <li><a href="/wiki/Supercharger" title="Supercharger">Supercharger</a></li> <li><a href="/wiki/Turbocharger" title="Turbocharger">Turbocharger</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Fuel system</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/Diesel_engine" title="Diesel engine">Diesel engine</a></li> <li><a href="/wiki/Petrol_engine" title="Petrol engine">Petrol engine</a></li> <li><a href="/wiki/Carburetor" title="Carburetor">Carburetor</a></li> <li><a href="/wiki/Fuel_filter" title="Fuel filter">Fuel filter</a></li> <li><a href="/wiki/Fuel_injection" title="Fuel injection">Fuel injection</a></li> <li><a href="/wiki/Fuel_pump" title="Fuel pump">Fuel pump</a></li> <li><a href="/wiki/Fuel_tank" title="Fuel tank">Fuel tank</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Ignition_system" title="Ignition system">Ignition</a></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/Ignition_magneto" title="Ignition magneto">Magneto</a></li> <li><a href="/wiki/Compression_ignition" class="mw-redirect" title="Compression ignition">Compression ignition</a></li> <li><a href="/wiki/Coil-on-plug_ignition" class="mw-redirect" title="Coil-on-plug ignition">Coil-on-plug</a></li> <li><a href="/wiki/Distributor" title="Distributor">Distributor</a></li> <li><a href="/wiki/Glow_plug_(diesel_engine)" class="mw-redirect" title="Glow plug (diesel engine)">Glow plug</a></li> <li><a href="/wiki/Ignition_coil" title="Ignition coil">Ignition coil</a></li> <li><a href="/wiki/Spark_plug" title="Spark plug">Spark plug</a></li> <li><a href="/wiki/Spark_plug_wires" title="Spark plug wires">Spark plug wires</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Engine management</div></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/Engine_control_unit" title="Engine control unit">Engine control unit (ECU)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><div style="display: inline-block; line-height: 1.2em; padding: .1em 0;">Electrical system</div></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/Alternator_(automotive)" title="Alternator (automotive)">Alternator</a></li> <li><a href="/wiki/Automotive_battery" title="Automotive battery">Battery</a></li> <li><a href="/wiki/Dynamo" title="Dynamo">Dynamo</a></li> <li><a href="/wiki/Starter_(engine)" title="Starter (engine)">Starter motor</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Intake system</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/Airbox" title="Airbox">Airbox</a></li> <li><a href="/wiki/Air_filter#Internal_combustion_engine_air_filters" title="Air filter">Air filter</a></li> <li><a href="/wiki/Idle_air_control_actuator" title="Idle air control actuator">Idle air control actuator</a></li> <li><a href="/wiki/Inlet_manifold" title="Inlet manifold">Inlet manifold</a></li> <li><a href="/wiki/MAP_sensor" title="MAP sensor">MAP sensor</a></li> <li><a href="/wiki/Mass_flow_sensor" title="Mass flow sensor">MAF sensor</a></li> <li><a href="/wiki/Throttle" title="Throttle">Throttle</a></li> <li><a href="/wiki/Throttle_position_sensor" title="Throttle position sensor">Throttle position sensor</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Exhaust_system" title="Exhaust system">Exhaust system</a></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/Catalytic_converter" title="Catalytic converter">Catalytic converter</a></li> <li><a href="/wiki/Diesel_particulate_filter" title="Diesel particulate filter">Diesel particulate filter</a></li> <li><a href="/wiki/Exhaust_gas_temperature_gauge" title="Exhaust gas temperature gauge">EGT sensor</a></li> <li><a href="/wiki/Exhaust_manifold" title="Exhaust manifold">Exhaust manifold</a></li> <li><a href="/wiki/Muffler" title="Muffler">Muffler</a></li> <li><a href="/wiki/Oxygen_sensor#Automotive_applications" title="Oxygen sensor">Oxygen sensor</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Internal_combustion_engine_cooling" title="Internal combustion engine cooling">Cooling system</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/Air_cooling" title="Air cooling">Air cooling</a></li> <li><a href="/wiki/Water_cooling" title="Water cooling">Water cooling</a></li></ul> <ul><li><a href="/wiki/Fan_(machine)" title="Fan (machine)">Electric fan</a></li> <li><a href="/wiki/Radiator_(engine_cooling)" title="Radiator (engine cooling)">Radiator</a></li> <li><a href="/wiki/Thermostat" title="Thermostat">Thermostat</a></li> <li><a href="/wiki/Fan_clutch" title="Fan clutch">Viscous fan (fan clutch)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Lubrication</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/Motor_oil" title="Motor oil">Oil</a></li> <li><a href="/wiki/Oil_filter" title="Oil filter">Oil filter</a></li> <li><a href="/wiki/Oil_pump_(internal_combustion_engine)" title="Oil pump (internal combustion engine)">Oil pump</a></li> <li><a href="/wiki/Sump" title="Sump">Sump</a> (<a href="/wiki/Wet_sump" title="Wet sump">Wet sump</a>, <a href="/wiki/Dry_sump" title="Dry sump">Dry sump</a>)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other</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/Engine_knocking" title="Engine knocking">Knocking / pinging</a></li> <li><a href="/wiki/Power_band" title="Power band">Power band</a></li> <li><a href="/wiki/Redline" title="Redline">Redline</a></li> <li><a href="/wiki/Stratified_charge_engine" title="Stratified charge engine">Stratified charge</a></li> <li><a href="/wiki/Dead_centre_(engineering)" title="Dead centre (engineering)">Top dead centre</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow hlist" colspan="2" 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