problems full throttle 3rd gear 6500-7000 RPM
I'm having problems with my '94 DE+T, breaks up/no accel around 6500-7000 in 3rd gear full throttle,
6975 rpm, 4.2v maf, 78% inj duty cycle - 1st & 2nd fine to redline.
3rd gear partial throttle fine to redline.
It was running good before the Chicago convention, until the day at the drag strip - 4th didn't engage, broke 3 rockers. Wes helped me put new rockers in, found all the shims, all the broken rocker parts.
Last fall the wastegate pipe weld cracked, no more boost, so it sat until this week. All welded up and good to go, other than this break up issue.
Setup:
94 SR20DE stock compression
JWT ECU & S3 cams
O2 induction intake manifold with IACV-AAC & air regulator installed
50 lb MSD @ 3 bar
Stock FPR - fuel pressure about 39psi @ idle (a bit too high)
AirResearch turbo @ 9psi, T3 .60 a/r, .63 wheel
unknown, probably rwd det exhaust manifold
2-1/2" crush bent downpipe to 3" side exit
Tial external wastegate
Z32 MAF blow through
Turboxs bov
Newer cap, rotor, OEM wires, NGK BKR7E @ 0.030" then 0.026" now 0.022"
"55" = no error codes
Vacuum @ idle about 12 in Hg
What I've tried so far:
Plugs were @ 0.030", so dropped them to 0.026" - didn't help.
BORNGEARHEAD stopped by and set timing and idle.
Timing was @ 25 degrees!!!
Now @ 15 degrees.
Checked compression - 180 - 180 - 180 - 178.
Made the problem worse! Happens in 2nd gear around 6500 RPM now.
Last fall I had a NISMO FPR on, but thought it was causing problems, so put a stock FPR on.
So, I put the Nismo FPR back on today.
Fuel pressure right on 36psi, 42psi no vacuum.
Dropped plug gap to 0.022".
Even worse yet. Breaks up around 5000 in 2nd gear now.
It ran better until 7000 in 3rd with 25 deg timing, 0.030" gap and 39psi fuel pressure.
Haven't done a boost leak check, need to make a tester, but it idles great.
6975 rpm, 4.2v maf, 78% inj duty cycle - 1st & 2nd fine to redline.
3rd gear partial throttle fine to redline.
It was running good before the Chicago convention, until the day at the drag strip - 4th didn't engage, broke 3 rockers. Wes helped me put new rockers in, found all the shims, all the broken rocker parts.
Last fall the wastegate pipe weld cracked, no more boost, so it sat until this week. All welded up and good to go, other than this break up issue.
Setup:
94 SR20DE stock compression
JWT ECU & S3 cams
O2 induction intake manifold with IACV-AAC & air regulator installed
50 lb MSD @ 3 bar
Stock FPR - fuel pressure about 39psi @ idle (a bit too high)
AirResearch turbo @ 9psi, T3 .60 a/r, .63 wheel
unknown, probably rwd det exhaust manifold
2-1/2" crush bent downpipe to 3" side exit
Tial external wastegate
Z32 MAF blow through
Turboxs bov
Newer cap, rotor, OEM wires, NGK BKR7E @ 0.030" then 0.026" now 0.022"
"55" = no error codes
Vacuum @ idle about 12 in Hg
What I've tried so far:
Plugs were @ 0.030", so dropped them to 0.026" - didn't help.
BORNGEARHEAD stopped by and set timing and idle.
Timing was @ 25 degrees!!!
Now @ 15 degrees.
Checked compression - 180 - 180 - 180 - 178.
Made the problem worse! Happens in 2nd gear around 6500 RPM now.
Last fall I had a NISMO FPR on, but thought it was causing problems, so put a stock FPR on.
So, I put the Nismo FPR back on today.
Fuel pressure right on 36psi, 42psi no vacuum.
Dropped plug gap to 0.022".
Even worse yet. Breaks up around 5000 in 2nd gear now.
It ran better until 7000 in 3rd with 25 deg timing, 0.030" gap and 39psi fuel pressure.
Haven't done a boost leak check, need to make a tester, but it idles great.