Can't keep the motor from detonating!

[tech3sandcars]

Sorry it has taken me a bit to respond, we have been doing testing, here is what I found out. Timing was not being automatically advanced because of current cut of the coils from over dwell, I tried dwells from 2.5ms to 3.5ms with no difference what so ever in timing at full RPM. Verified this with a timing light. My timing table is now set at under load to a maximum of 34deg, seems low to me. In order to get rid of the detonation the mixture has to be as fat as 10.5:1 at peak torque at about 4500rpm, From that RPM on up, any leaner than 11.5 my knock meter will start to trip the knock light.

I suspected the O2 meter was messed up, so I have another portable unit, it that reads the same as my AEM guage that I am using for MS2.

I got it to run good and pull pretty good thru the RPM range in all gears, I'm just wondering how much power I am missing with less than desirable advance and a fat mixture. This one is just puzzling. I have done a lot of these and never had this issue.

[tech3sandcars]

Alright so I'm at an airport bored and doing some more research, this motor has 10.7:1 compression, about a point higher than I thought, so my timing may not be too far off, its now the rich mixture I am concerned about, by the way running premium pump gas.

Any ideas?

[subwoofer]

You may be over advancing it? 34 degrees advance @ full load may be excessive, to my knowledge a good/decent 4-valve pent roof chamber should level off power wise (MBT) at < 30 degrees, and there is nothing to be gained except wear and tear in advancing past this point.