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Short version:
MSM dedicated track car rebuilt last winter
MSM MS3Pro PnP ECU that has been in car for over 50 track hours PRIOR to rebuild
Wiseco 8.5:1 83.5mm pistons
Eagle rods
FlowForce 640ish injectors
Stock turbo
Stock ignition coils
93 octane
Some kind of Saab intercooler
13psi
about 218 whp
10.5-11 AFR
It ran about 10 track hours
cylinders 1 and 4 failed due to detonation
Why 1 & 4 ?
4 is on the left 4 and 1 1 4 1 on the left 2&3
Last edited by Elmos hers; 07-21-2018 at 08:18 PM.
Reason: added info
Yes, 1 and 4 share a coil. I’m having trouble understanding how a loose connection would cause detonation. I’ve detected no misfire.
EGTs appeared to be lower on 1&4 than on 2&3
At this point I think that was due to the detonation.
We figured the bad power supply was upsetting the ecu and its internal timing thus messing with the ignition timing. I felt nothing in that circumstance either (well until the engine failed, i felt that )
Its highly unlikely but worth checking.
Your map seems conservative and your efr's 'seem' quite rich so it has to be something putting the timing off....incorrect dwell, timing trigger setting or something liek that.
Anyway, im stretched already so hopefully someone with more experience can chip in.
Way too much timing on an MSM, I typically can only get 14 degrees in at 12+psi.
You were knocking when you were tuned.
We did not observe knock when we were tuning.
I have a Chatterbox spliced into the OEM knock sensor to listen in.
Would anyone share a successful timing map for reference?
Any thoughts on why 1&4 are severely damaged and 2&3 have none?