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View Full Version : egts and knock sensor



Stinkbox
04-20-2007, 11:09 AM
ok. im running 20psi on stock mp computer with elec coost cut elim and 390 dsm injectors with garrett t2 and front mount on my 90 shelby. egts were @ 1450 for alittle bit then developed a bad exhaust leak @ turbo and mani. egts eventually were 1650+. fixed leak and reset ecu, egts back to 1450 for about 10 miles. blew off intercooler pipe, fixed it and next pull back to 1650+. im thinking its due to knock sensor picking ---- up. how long after knock sensor activity does it keep ignition retarted? im gonna reset ecu again today to see if thats it.

are high egts really bad for your car when ignition is retarted. i know if your getting it do to too much advance kaboom but what about not enough.

puppet
04-22-2007, 08:30 PM
High EGT's are not good for the turbo. Your ignition may be retarded enough to cause high exhaust temps .... regardless of A/F ratio. The burn event is moved far enough back to be continuing in the exhaust manifold, blow torching the EGT probe.

With the warmer weather you may be looking to back off the fuel a few lbs. See if this impacts the EGT's in a favorable way. Stop reducing fuel when the EGTs start climbing again. Put a little back in and your there.

Some guys like to start with the ignition timing first off. Tuning it for best torque/HP ... then tweak the A/F using the EGT as a reference.