Thread: sr running wierd

ill keep it simple.
at about 90% throttle, she runs good as hell. almost all my power is there. at wot though, as soon as it hits 20psi, it starts missing and spiking.
it JUST started doing this. it only does this at wot. went from iridium 7 plugs to 6's and the problems still there. gapped them from .030 to .029 and it still does it - only at wot. runs like a raped ape otherwise.
changed out the fuel filter tonight, checked and set timing, looked for vacuum leaks and found none, checked all clamps and all were tight - suspect tps because its close to being at the end of the adjustment slots.
more info needed?
please point me in a direction, im kind of miffed right now.

oh yeah, what o2 sensor do we run? the one in there now is the u.s. style one with the larger o2 sensor and not the smaller jdm type.
i also need to know what the voltage should be on the tps so i can check that as well.

Do you have a wideband? Also, need to know what´s your setup and ECU.

I had a similar problem and had to adjust fuel pressure.

i have a wideband - not installed, so i guess thats no, lol.
redtop rwd
z32 maf
jwt ecu
gt2871r
je pistons
eagle rods
aeromotive fpr
walbro 255
740cc rc's
cosworth hg

checked the tps, it wouldnt hold a voltage so i replaced it with one that would. set it and its still doing it. changed the plugs again and closed the gap another .001. havent had a chance to drive it yet though...
checked the plugs and they looked good. wish i could figure this one out.

I had a similar problem, and it was the A/F ratio. It was running pig rich at WOT, around 8 or 9. Since I don´t have a SAFC or Calum ECU, I closed the AFPR to bring it up to 11.5 at WOT.

i checked the afpr on mine and it was several psi too high. i fixed that when i fixed the tps. still doing it...