Well ive nearly finished the IROC now. But it still 'bogs down' when i just stomp the peddel. So i have to ease the throttle on to accelerate smoothly. And its starts to spluter a bit at full throttle.

My first guess is im lossing fuel pressure initailly when i launch it and then at WOT. Once ive made up the line for the fuel pressure guage i guess ill know more. I know its just slack of me, but i thought running only 3psi, i could get away without installing the RRFMU and external pump. Oh well. I guess ill have to throw them in.

Did you guess just wire your external pumps in to be on with ignition power? or relayed off the stock pump signal?

Its still unintercooled and really start to run like a pig after driving around in the heat for an hour or so (40deg C), so hopefully the FMIC will arrive shortly and solve that for me.

Anyway, heres a quick vid we took yesterday. Like i said, i cant just launch hard so i had to 'stage' up slightly to get past the 'bog'.

http://ausraptor.net/droopz/Nomuffnetedit.mpg 35mb (sorry)

 

Cool man, lookin good. I've followed your (and everyone elses, hehe) turbo build for a while now. Got any pics with the new hood?

3 psi? Definitely upgrade the fuel system and when you get the IC crank it up some. Do you have any numbers for it yet?

I don't know why it is bogging from an initial throttle stab, but it shouldn't have to do with the turbo as it isn't making boost immediately, right?

As for the pump, just relay it off the stock FP signal. That way you'll be sure they're both on at the same time.

 

New hood;




Your probly right about the bogging down not being turbo related. I might have to check my TPS since it might have been knocked during the build. Would that also account for the stutter at WOT?

 

Have you tunned your car? If its speed density the map sensor might be having problems under boost.

 

Don't overlook the simple things like spark plugs. I had a spark-blow-out issue with my turbo Z24. For the first 5k miles or so, it ran great, then started to misfire at WOT, high boost, and high RPMs, especially at the top end of third and fourth gears. Turned out that the plug gaps opened up from my initial .040" gap to around .045", which was too much for the ignition to fire consistantly under these severe conditions. A simple spark plug replacement and a tighter (.035") gap solved the misfire.

 

I think ive found my problem. Driving around last night i noticed i definatly have a power related miss (each time it would bog, spluter or surge the headlights would dim). Either a buggered dizzy/rotor, worn lead or even a plug gap thats too wide and thats getting blown out i reckon.