http://s4wiki.com/mediawiki/index.php?action=history&feed=atom&title=Blow_off_valve 2026-04-12T23:09:57Z Revision history for this page on the wiki MediaWiki 1.43.8 http://s4wiki.com/mediawiki/index.php?title=Blow_off_valve&diff=1946&oldid=prev 2006-09-02T00:28:30Z

<p></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 00:28, 2 September 2006</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 10:</td> <td colspan="2" class="diff-lineno">Line 10:</td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system should be equipped with [[bypass valve]]s. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always [[wide open throttle]]. The LTFT function is often entirely disabled or non-existant, since a standalone EMS is generally used (such as Motec).</div></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system should be equipped with [[bypass valve]]s. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always [[wide open throttle]]. The LTFT function is often entirely disabled or non-existant, since a standalone EMS is generally used (such as Motec).</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>[[Category:Tuning]]</div></td> </tr> <!-- diff cache key wikidb-s4_:diff:1.41:old-1818:rev-1946:wikidiff2=table:1.14.1:bc2a06be --> </table>

Nyet http://s4wiki.com/mediawiki/index.php?title=Blow_off_valve&diff=1818&oldid=prev 2006-08-23T17:33:18Z

<p></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 17:33, 23 August 2006</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 1:</td> <td colspan="2" class="diff-lineno">Line 1:</td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>a.k.a. "BOV"</div></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>a.k.a. "BOV"</div></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>Valve which relieves charge pressure by venting air to atmosphere.</div></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Valve which relieves charge pressure by venting air to<ins style="font-weight: bold; text-decoration: none;"> the</ins> atmosphere.</div></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Prevents [[turbo surge]], but may affect [[LTFT]]s.</div></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Prevents [[turbo surge]], but may affect [[LTFT]]s.</div></td> </tr> <tr> <td colspan="2" class="diff-lineno">Line 9:</td> <td colspan="2" class="diff-lineno">Line 9:</td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving conditions and driver behavior.</div></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving conditions and driver behavior.</div></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system should be equipped with [[bypass valve]]s. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always [[wide open throttle]]. The LTFT function is often entirely disabled.</div></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system should be equipped with [[bypass valve]]s. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always [[wide open throttle]]. The LTFT function is often entirely disabled<ins style="font-weight: bold; text-decoration: none;"> or non-existant, since a standalone EMS is generally used (such as Motec)</ins>.</div></td> </tr> <!-- diff cache key wikidb-s4_:diff:1.41:old-1722:rev-1818:wikidiff2=table:1.14.1:bc2a06be --> </table>

Nyet http://s4wiki.com/mediawiki/index.php?title=Blow_off_valve&diff=1722&oldid=prev 2006-08-17T17:34:25Z

<p></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 17:34, 17 August 2006</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 9:</td> <td colspan="2" class="diff-lineno">Line 9:</td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving conditions and driver behavior.</div></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving conditions and driver behavior.</div></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system should be equipped with [[bypass valve]]s. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always <del style="font-weight: bold; text-decoration: none;">WOT</del>. The LTFT function is often entirely disabled.</div></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system should be equipped with [[bypass valve]]s. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always <ins style="font-weight: bold; text-decoration: none;">[[wide open throttle]]</ins>. The LTFT function is often entirely disabled.</div></td> </tr> </table>

Nyet http://s4wiki.com/mediawiki/index.php?title=Blow_off_valve&diff=1717&oldid=prev 2006-08-17T17:30:30Z

<p></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 17:30, 17 August 2006</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 9:</td> <td colspan="2" class="diff-lineno">Line 9:</td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving conditions and driver behavior.</div></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving conditions and driver behavior.</div></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system<del style="font-weight: bold; text-decoration: none;">,</del> <del style="font-weight: bold; text-decoration: none;">the</del> <del style="font-weight: bold; text-decoration: none;">use</del> <del style="font-weight: bold; text-decoration: none;">of</del> [[bypass valve]]s<del style="font-weight: bold; text-decoration: none;"> is preferred</del>. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always WOT. The LTFT function is often entirely disabled.</div></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system <ins style="font-weight: bold; text-decoration: none;">should</ins> <ins style="font-weight: bold; text-decoration: none;">be</ins> <ins style="font-weight: bold; text-decoration: none;">equipped with</ins> [[bypass valve]]s. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always WOT. The LTFT function is often entirely disabled.</div></td> </tr> </table>

Nyet http://s4wiki.com/mediawiki/index.php?title=Blow_off_valve&diff=1716&oldid=prev 2006-08-17T17:29:55Z

<p></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 17:29, 17 August 2006</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 5:</td> <td colspan="2" class="diff-lineno">Line 5:</td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Prevents [[turbo surge]], but may affect [[LTFT]]s.</div></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>Prevents [[turbo surge]], but may affect [[LTFT]]s.</div></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>How? BOVs can release measured air from the intake system, and when they do, they make the ECU "think" there is more air in the combustion chamber than there really is. This will cause the car to run rich during closed loop operation, and to compensate, <del style="font-weight: bold; text-decoration: none;">LTFTs</del> will go down. However the car may still run rich (or lean) during closed loop operation, since the LTFTs only reflect recent condions, and if the BOVs are venting more (or less) often than they were recently, the LTFT will be wrong. To make matters worse, the car can also run rich open loop, again depending on how much air was lost while the BOVs were venting.</div></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>How? BOVs can release measured air from the intake system, and when they do, they make the <ins style="font-weight: bold; text-decoration: none;">[[</ins>ECU<ins style="font-weight: bold; text-decoration: none;">]]</ins> "think" there is more air in the combustion chamber than there really is. This will cause the car to run rich during closed loop operation, and to compensate, <ins style="font-weight: bold; text-decoration: none;">[[LTFT]]s</ins> will go down. However the car may still run rich (or lean) during closed loop operation, since the LTFTs only reflect recent condions, and if the BOVs are venting more (or less) often than they were recently, the LTFT will be wrong. To make matters worse, the car can also run rich open loop, again depending on how much air was lost while the BOVs were venting.</div></td> </tr> <tr> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> <td class="diff-marker"></td> <td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td class="diff-marker" data-marker="−"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving <del style="font-weight: bold; text-decoration: none;">condtions</del> and driver behavior.</div></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving <ins style="font-weight: bold; text-decoration: none;">conditions</ins> and driver behavior.</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>For this reason, any street car that uses [[MAF]]s upstream of a charge pressure relief system, the use of [[bypass valve]]s is preferred. In racing applications, the use of BOVs is common since partial throttle behavior is unimportant, and non-coasting/non-braking driving conditions are almost always WOT. The LTFT function is often entirely disabled.</div></td> </tr> </table>

Nyet http://s4wiki.com/mediawiki/index.php?title=Blow_off_valve&diff=1712&oldid=prev 2006-08-17T17:23:20Z

<p></p> <table style="background-color: #fff; color: #202122;" data-mw="interface"> <col class="diff-marker" /> <col class="diff-content" /> <col class="diff-marker" /> <col class="diff-content" /> <tr class="diff-title" lang="en"> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td> <td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 17:23, 17 August 2006</td> </tr><tr> <td colspan="2" class="diff-lineno">Line 1:</td> <td colspan="2" class="diff-lineno">Line 1:</td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>a.k.a. "BOV"</div></td> </tr> <tr> <td class="diff-marker"><a class="mw-diff-movedpara-left" title="Paragraph was moved. Click to jump to new location." href="#movedpara_2_1_rhs">&#x26AB;</a></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div><a name="movedpara_1_0_lhs"></a>Valve which relieves pressure <del style="font-weight: bold; text-decoration: none;">to</del> <del style="font-weight: bold; text-decoration: none;">atmosphere</del> to <del style="font-weight: bold; text-decoration: none;">prevent surge</del></div></td> <td colspan="2" class="diff-empty diff-side-added"></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker"><a class="mw-diff-movedpara-right" title="Paragraph was moved. Click to jump to old location." href="#movedpara_1_0_lhs">&#x26AB;</a></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div><a name="movedpara_2_1_rhs"></a>Valve which relieves<ins style="font-weight: bold; text-decoration: none;"> charge</ins> pressure <ins style="font-weight: bold; text-decoration: none;">by</ins> <ins style="font-weight: bold; text-decoration: none;">venting air</ins> to <ins style="font-weight: bold; text-decoration: none;">atmosphere.</ins></div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>Prevents [[turbo surge]], but may affect [[LTFT]]s.</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>How? BOVs can release measured air from the intake system, and when they do, they make the ECU "think" there is more air in the combustion chamber than there really is. This will cause the car to run rich during closed loop operation, and to compensate, LTFTs will go down. However the car may still run rich (or lean) during closed loop operation, since the LTFTs only reflect recent condions, and if the BOVs are venting more (or less) often than they were recently, the LTFT will be wrong. To make matters worse, the car can also run rich open loop, again depending on how much air was lost while the BOVs were venting.</div></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><br /></td> </tr> <tr> <td colspan="2" class="diff-empty diff-side-deleted"></td> <td class="diff-marker" data-marker="+"></td> <td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>This fudge factor (both in partial and wide open throttle operation) is almost impossible to properly correct for, since it varies wildly depending on driving condtions and driver behavior.</div></td> </tr> </table>

Nyet http://s4wiki.com/mediawiki/index.php?title=Blow_off_valve&diff=1705&oldid=prev 2006-08-17T17:13:07Z

<p></p> <p><b>New page</b></p><div>Valve which relieves pressure to atmosphere to prevent surge</div>

Nyet