Another "recommend a cylinder head?" thread!

Can you share with us under what situations and conditions does this detonate?

And yes, on the pistons used, and also, did the heads get milled? If so, how much? Just looking for data to see which AL heads might work.

As an option, it would be easy and relatively cheap to lower the SCR with thicker head gaskets; you can drop your SCR to 9.5 with an approximate .050" increase in head gasket thickness. Do you recall which ones you used? If Felpros, were they out of a standard Felpro gasket set?

What cam do you have? One with slower ramps between .050" and advertised durations will close the intake later, and lower DCR. And if the cam is advanced, retarding it a few degrees will help a bit too.