8.5:1 compression ratio. I was running 91oct pump with just a couple gallons of 100 octane in there. 24psi run for about 4-5 runs. Then some street abuse.
I think the melted pistons started there, then progressively got worse as the factory rev limiter was nailed on daily. Every time I would hit the limiter with extreme prejudice I would get counts of knock.
Even on 15-16psi.
I have my new thread open now, and the new motor made great power for low boost. The AFR are still pretty lean, about 12:1 on peak torque. but at peak hp it is about 11.6:1. I richened up the mixture to help resolve any mid-range knock, though the knock light never hit knock in the mid-range. Only at the rev limiter.
I am now going to hit about 11.7:1 peak torque and around 11.2-11.4 at peak hp. I also am going to play around with the dizzy timing just a little bit on the dyno to find where it likes it. I was told to put in some timing until I start to lose power, then take out 2*. Perhaps I will try that. Timing has such a huge impact to the powerband.
I think the melted pistons started there, then progressively got worse as the factory rev limiter was nailed on daily. Every time I would hit the limiter with extreme prejudice I would get counts of knock.
Even on 15-16psi.I have my new thread open now, and the new motor made great power for low boost. The AFR are still pretty lean, about 12:1 on peak torque. but at peak hp it is about 11.6:1. I richened up the mixture to help resolve any mid-range knock, though the knock light never hit knock in the mid-range. Only at the rev limiter.
I am now going to hit about 11.7:1 peak torque and around 11.2-11.4 at peak hp. I also am going to play around with the dizzy timing just a little bit on the dyno to find where it likes it. I was told to put in some timing until I start to lose power, then take out 2*. Perhaps I will try that. Timing has such a huge impact to the powerband.
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