Thread: 04 GTP questions, seeking mod advice

yes you need at least 42# injectors and if plan any further mods 60#. You will need a fuel filter. change it after a week of running the E85. You shouldn't need exhaust work. Downpipe helps. 180* thermostat, smaller gap on plugs, with no other mods I would think 3.6 maybe 3.5 with a proper tune.

Originally Posted by rickisrad

yes you need at least 42# injectors and if plan any further mods 60#. You will need a fuel filter. change it after a week of running the E85. You shouldn't need exhaust work. Downpipe helps. 180* thermostat, smaller gap on plugs, with no other mods I would think 3.6 maybe 3.5 with a proper tune.

I'd recommend exhaust work on ANY 3800...of any level of modding.

It's god awful. The catback is fine; but everything else needs help. Manifold casting is crap, the downpipe is tiny, and the U-Bend is even worse.

On a stock car, PEM's and a 3" downpipe would probably add 15-20~ horse...and most of that would just be killing all the KR.

Originally Posted by blueguy91

I'd recommend exhaust work on ANY 3800...of any level of modding.

It's god awful. The catback is fine; but everything else needs help. Manifold casting is crap, the downpipe is tiny, and the U-Bend is even worse.

On a stock car, PEM's and a 3" downpipe would probably add 15-20~ horse...and most of that would just be killing all the KR.

I have been trying to figure out how much it would cost me to do headers, but I'm starting to see that I might have major issues passing emissions inspections here if I go that route. I would pretty much have to run a stock catalytic converter to avoid setting a code, and ANY code thrown during the emissions inspection here will fail the test (even if it's not emissions related!). And you can't have the codes deleted or emulated, because they actually do an OBDII test that basically checks to see if the PCM has been coded to ignore emissions DTCs or anything else to get around emissions.

So now I'm considering 1.9 rockers and a good tune, but it seems a shame to leave the stock exhaust system in place. Maybe I could have an exhaust shop here build something for me? Might be too expensive for me though.