Timing on high cr NA

[mach5camaross]

So I built an engine for my 91 and used left over parts from several projects. 90.5mm sohc pistons, I would guess that would make it 11.5-1 give or take. stock thickness cometic with the larger id for the .60 over pistons, arp head studs, stock cams. Intake, header, no cat, 2.5 in exhaust.

Started the car and runs great, took it for a drive and could hear it ping when just srating to accelerate then went away. tweeked the timing back to 22 btdc and then 24 now it rattles like a diesel when accelerating in 2nd from 5mph. reset timing again to 18. sound beter. advanced it 1/8 inch at a time till no ping on 91. I suppose if I would slow the idle down now to 700 and throw a light on it I would be about 12-13 btdc.

So I have about 35 miles intown driving and it runs great had it up around 50-55 and up to around 4500 rpm and even lugged it down in 5th a little.

So what long term or short term problems am I going to run into with the timing set like this? Car is also hella rich and noticed it more and more. Put 33miles on tonight, had some idle time, and went through not quiet a tank of gas, I guess I have not put some in so I do not know how much its sucking.
Modified by mach5camaross at 11:04 PM 4/29/2008