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onefastcar
05-20-2006, 09:21 AM
Ok couple questions what is a stock set up at on timing.
if you retard an engine and it runs better what would cause this, i hear that every engine is different and that some like advance and some like retarded timing, but what would cause it to like either or.
My last question or maybe statement is on a stock car you can't adjust this correct (timing) so how would it be fixed, because now adays we have items that will adjust this for ya (chips, translators and so on).

kenmosher
05-21-2006, 10:08 AM
Timing is basically a funciton of combustion chamber design, fuel/air stratification in the cylinder, squish area, piston velocity, spark plug location, valve timing, and fuel quality.

That's why timing is variable based on load, RPM, MAP, etc.

The ECM constantly varies the timing to as close to optimal as possible. Stock timing, as controlled by the ECM and the chip, assumes you are looking for best emissions, best reliability, and you are running stock boost levels.

The aftermarket chips adjust the timing tables to take into account non-stock boost levels, enhanced performance, aftermarket parts (like injectors), etc. Usually this involves a timing curve that reduces timing under high boost with an aftermarket turbo (due to many complex reasons, including exhuast back pressure and turbo efficiency at high boost).

Often times, low end timing may be slightly retard to generate higher low RPM EGTs to spool the turbo quicker ... turbo spooling is affected by the heat in the exhaust.

PaCemkr86
05-21-2006, 03:32 PM
before i got my alky kit, i kept pulling the timming back with my translator unitl i didnt have any more Knock Retard with 18#

onefastcar
05-22-2006, 07:27 PM
The reason i ask is that prior to i was running 2 deg advance and was getting what sounded like was valve train noise and backfiring. Well i decided at idle to start adjusting my timing by listening i finally got to 8 deg retard and i stopped best sounding idle and when i punch it now i have no backfire or valve train noise does this sound right by the way i have a trans + and this is what i am adjusting the settings with, really runs the best it has, will there be any issues running like this, also at this time i am running 18 pounds of boost but want to go to 22 when i feel comfortable?