is it fatal

I have a pettit tuned (AUTOMATIC) FD with around 3k miles on it. Off the Shelf street port engine with 2mm apex seals, new rotor housings, etc. It is making about 310whp, and running off the stock ECU. Sometimes at full throttle the car feels as slow as my G35 coupe...when other times it feels as fast as a car with 310whp would feel. My question is...why does it accellerate fine sometimes and sluggish at other times? Does it have to do with the stock ECU and A/F ratios? I really don't know too much about these engines and i wanted some insight. Thanks in advance.

BoostCrzy

does it do it more often with different temps??....

is it fatal

engine temp is always the same. Environmental temp is not a factor. It was chilly outside tonight and the car was sluggish, whereas the car has performed well in hot and cold weather...as well as poorly.

jeff p

is the ecu re chipped by pettit ? I was told they will not re chip the auto ecu's. I would like to get mine re chipped if they could get it to work right. let me know what number ecu you have.

Jeff

is it fatal

nah it wasn't rechipped. I wonder if that is the problem..they told me that the stock ecu doesn't respond well to mods with an automatic trans

Monsterbox

iTrader: (6)

get it on a wideband ASAP...there NO way i can think of that you are running safely 310rwhp on stock ecu map

is it fatal

oh i understand what you were saying. it WAS remapped...i thought by "rechipped" you mean it had a new chip.

jeff p

I think your problem is the street port. since you have the stock ecu you can't tune for it . get a PFS purple ECU in the for sale section and have it tuned for the porting. I think you will be happy after this.

Jeff

is it fatal

oh i understand what you were saying. it WAS remapped...i thought by "rechipped" you meant it had a new chip. any other thoughts?

jeff p

when I talked to jeff at pettit he said the auto rechipped ecu's had problems. so they no longer do them. get the PFS box with pink nine software and keypad so you can tune it for the porting.

Jeff

jeff p

also when you drive keep the car in 2nd gear until 40 mph then shift to (D) drive for you top end and freeway speeds. this will help with the bogging . it seems when the car is in (D) drive all the time it goes int overdrive easy and the ecu dumps a lot of fuel cousing the bogging. also when you smog test the car have the tech start in 1st gear until 15 mph then shift to 2nd for the rest of the test and you will pass ok. thats how I found out about the fuel issue when it hits overdrive the ecu gets very rich and you will fail the test . hope this helps.

Jeff

is it fatal

i appreciate the help everyone.