Quote:
Originally Posted by KingLT1
What tends to happens with larger throttle bodies and especially on some aftermarket stuff is the timing will drop down at idle because the throttle blade angle is off. So the ECU pulls timing in order to hit target idle. Since we don't have access to all the throttle body tables like gen 4 stuff, you have to go into the Virtual torque editor and remove torque from the idle range area to get the ECU to add spark back. On a stock cam car the lower timing will likely go undetected to the average person. On a cam car it will run like crap because the cam needs more timing due to the lack of efficiency down low.
There is a popular brand throttle body that I won't name that is notorious for this...(Hint: they claim 107mm effective.)  |
I know this brand, LOL. However - I'll say, that because I over-ported an LT5 in the past, the tune was already modified with the torque modification you're talking about, so when we installed the "107", when we went through the relearn procedure, it was totally fine. I couldn't say if I didn't already deal with the over-ported LT5 that the 107 wouldn't have been as easy, but all I know is we have 10* at idle, and could command more if we wanted, and it's just fine. I read about some of the stuff I think you're talking about though. Oof. No problems for me though (not because I'm a good
tooner or something - just ?probably? because of that LT5-experience).
That TB was worth it for that car's combination though. It lowered inlet vacuum 4-5 kPa at WOT, surprisingly. And that was coming from a less-over-ported LT5.