The Panhead & Flathead Site

Description: How much displacement will stock heads support?

Post by hav2mod on Jan 30, 2006, 5:26am

My first post, but I've been lurking around here over a year from the company's 'puter (sceered to post).
How much displacement will stock heads support? And what about the squish pipe exhaust? This looks restrictive as hell to me. Thanks to all, this forum is the best.

Post by 65panhed on Jan 30, 2006, 4:25pm

I'm running the S&S 88" stock bore stroker kit with .060 over ( 80" bore) for a total of around 92 ". It runs really great, kick starts fine and runs with the best of them. I believe it might run better with the STD heads because they address the intake manifold issue and come ported from STD. I believe my heads have the larger shovel valves but its been so long I can't be sure. The stroker kit is 4 3/4" stroke with series 92-2906 pistons for about 9:1 compression on top of a sifton 109 avenger cam which makes this sled what it is.

Post by hav2mod on Feb 2, 2006, 2:26pm

65 panhed, Thanks for the reply. My motor's basically stock. I hate to change the looks of the motor but I know the stock intake manifold has it's limitations. I've only been running the pan for two years. I'm doing build research now. Can anyone tell me if the squish pipe exhaust robs power? Mine looks real flat where it exits the frame&motor. Thanks