[Keithc8]

The problem with this head and the old hemi head is not so much the location of the plug which is real close to the center but the size of the cmaber and how far away the plug is away from zero deck.
The smaller chambers with the plug located close to the center run the least amount of timing. Like the Yates heads, Cheverolet 18 degree heads with the small chambers. These heads are in the 35 to 40 cc range and you run a flat top or a reverse dome pistons.

Thanks, Keith