Well, I'm a newbie, and thought maybe this would be a good place to post this question. If it's not the right place, feel free to move it or delete it.
I have a '66 Chevelle with a 327 in it- I built the 327 myself. It has 10.5:1 pistons in it, and they are running under camel hump/double hump heads with 64cc combustion chambers. The combo together is putting me at around 11:1. The cam is a 272/284 duration cam.
I'm running HEI and although friends claim it should be possible, I cannot run 93 octane in this engine without it pinging. I have to run a minimum of 98 octane. I've been told by a few people that I should be able to just retard the timing to fix it, but I don't think that is accurate.
What is everyone's take here on the scenario? I will say too that all that's on the engine is the HEI distributor, no added aftermarket timing add-ons or anything. And when it comes to timing, I know how to read a chilton manual, find the suggested timing, move the distributor to it, and that's about it. The car is a plain-old cruiser, so $8.49/gallon really slows up the cruises!
Thanks in advance,
Jim