New freshly built kaZ31 T3 turboLarge custom FMICCustom log mani2.5" mandrel dp85mm HKS Hi-power exhaustWalbro 190 fuel pump370cc injectors, Z32 fuel filterJWT ecu, tuned for 370cc, turbo, ka mafJWT POP charger
Heres what ive replaced, and checked, and checked again over the past 6 months:
Fuel filterair filterfuel pressurebase timinginjectorsmafcoilcap and rotorspark plugs, gaps, typesintake charge temps (101º highest it ever got)
heres the situation:when i first got the kat, i had this pinging, at 20º base timing, even at 1psi, it would ping. i retarded the timing to 15º and ran 6psi safely w.o pinging (much), and the car ran, but was slow.
one day i decide to run the stock ecu on the 370cc injectors, and it runs absolutely fine, (strange isnt it). started pinging above 7psi tho.
got tired of all the nonsense and drove to JWT to have them strap it to the dyno. they played with the ecu, said nothing was wrong as far as they could see, and richened up the ecu program. the car made 248rwhp at ~10 psi, and did not detonate nor misfire or anything on the dyno, which i believe showed 10.8:1 on the Horiba A/F wideband.
Jim and i went for a drive, and the car did fine on at 7psi, but at 9-10 psi, the pinging was VERY minor, but still present. Jim said to test the intake charge temps, and feared my ugly DP design may be a problem, along w/ my old stock plug wires. so i went home and began remedying this list of issues.
I changed the downpipe to 2.5" bandrel, smooth bends -- no change on detonation.
I changed the exhaust for fear of backpressure (i had 60mm) to 85mm -- no change in detonation
I checked the intake charge temps as i boosted 9psi for 1 minute + uphill on a hot day, 101º, lets say that the $15 walmart gauge was off 30º and its actually 131º, thats STILL not so bad.
I checked for air leaks, and found that the barb under the throttle plate was open and leading nowhere, plugged that and - no change in detonation.
The car will not detonate if i floor it in 5th and go from 50-80, but 50-110 itll start to detonate above 100. On certain nights, the detonation is LOUD and apparent, for no reason. Most of the time, if i top off 2nd and go to 3rd, i know itll ping 4k+ in 3rd.
For the love of god, i have tried EVERYTHING to remedy this problem, and not a soul seems to know what it could be. the ONLY thing i havent done is new spark plug wires, but id blame misfire on that, not detonation, eh?
Im at the end of my wits here. they say that the Z31 turbo may be bad for the KA, but it seems the other current thread would say otherwise. guys, HELP! :help :help
-Abe
