You may want to invest in a good Pyro meter set. It will help with seeing issues like you are having. Should help prevent you going into melt down. If you pay attention to it.The new engine went great... until it didn’t. It cracked all the ring lands and burnt through piston 5 while afr were at 10.8. It appears i have a triggering/reference/timing drift issue that results in the engine seeing significantly more timing than called for or reported which is quite possibly causing this run of failures.
I did 10+ 0-200kmh pulls and everything was logged and fine, i put it on a trailer and towed it 500km to roll racing and it failed in under 9 seconds.
Current plan is to assemble a cheap disposable motor so that we can put it on an oscilloscope and check the crank reluctor waveform against whats reported in the ecu, closely inspect all of the wiring and connections, make a new tefzel injector harness, give control of the vvti to my aftermarket ecu so that it can monitor and log the intake cam position in relation to afrs and all of the other logged channels. If i am unable to track down an issue that i am confident is causing it my ecu will be sent away and run on a bench with a simulator program to test all of the inputs and outputs.
The biggest issue is that none of my failsafes catch it before it destroys itself due to it being timing trigger related and on e85 so there is no audible knock, afr, fuel pressure, coolant temp, boost pressure all log well within spec.
i have it all running again, diff ratio is now 3.73:1 my loose torque converter has 100kmh cruise at about 3200rpm compared to 3800rpm of the 4.3:1 set. The fresh engine is running fine, i had to reshim a few of the buckets in the head to get rid of some valve train noise and adjust the pinion bearing preload on my rear diff as it was a touch noisey. I’ve run the new engine in on 50/50 blend of 98/e85 on maximum of 18psi, even with the awd, 265 rears and 235 fronts it still has the traction light flickering at 150kmh indicating the traction control is taking action and braking wheels as required. It’s virtually un-noticeable handling wise when it is intervening. As of this afternoon ive run the tank right down and added e85 so over the next week i’ll try turning it up a bit on e85 traction permitting. Heres a pic of my matching work ute and race car. 😂 View attachment 133130
What car did you get the 3.73 front differential from?