I have an 03 g coupe/ manual with a ATI procharger running 350 whp and 299tq at 8 psi. I just added stillen dual exhaust/race pipe/ headers all at once. I took it back to the same dyno and loss 20whp and 10tq. I am using the EFMU that came with the procharger. Can anyone tell me what I did wrong?

 

what you did wrong? clearly changing your setup screwed it all up, and probably the emfu that came w/it.. get utec at very least

 

how come other g owners gained from the mods

 

depend on the piping on the exhaust, we know nothing about your setup.

what size injectors?
what supporting mods?
etc..

by adding this stuff you could be hurting your setup by too much "flow" in the system.

 

i got stock injectors and everything else stock. should i take the headers off? Procharger told me i was gonna lose boost 1-2 but gain hp with the set up

 

what mods did you have done to your car before you changed your setup

 

just the procharger kit on stock car

 

if im not mistaken.. for supercharger setups its better to have back pressure, as opposed to turbos where less back pressure is more efficient. but i honestly think adding all those breather mods just made everything "flow" too much. reasearch more on this, i would get bigger injectors btw

 

from what i understand enough back pressure has more to do with a root style like stillen then a centificul like procharger and vortech

 

I asked stillen and procharger before I purchased the mods and they both agreed that I would gain HP but lose 1-2 psi

 

would a utec , walbrow fuel pump, and bigger injectors be everything I need to do?

 

yeah that would definately help. but sounds like you need to reasearch more about FI on our cars. but anything you do with a stillen roots kit you will lose hp. but im not as savvy when it comes to sc's as i am with turbos but yeah i would say you got too much flow throughout your system

 

You need a new tune after doing those mods or you'll lose HP. Check on my350z there's a new thread from sharif, perfect example of this.

 

thank's for your help I thought I was doing everything right but I'm learniing now (the hard way).

 

http://my350z.com/forum/engine-and-d...-required.html