View Single Post
  #91  
Old 04-23-2021, 03:34 PM
MarkS57's Avatar
MarkS57 MarkS57 is offline
Chief Ponti-yacker
 
Join Date: Jun 2015
Location: Flemington, NJ
Posts: 612
Default

Quote:
Originally Posted by Formulajones View Post
Must be something new because 25 years ago the L2257 TRW 428 piston was a flat top.

I had to machine a dish in them, which ended up being 16cc. Then zero decked the block, or close to it (.004" in the hole) and with a .038 gasket and a 76cc head I had 9.7:1 compression.

Ran that engine for a couple decades on pump gas.
There could be a flat top version, TRW had flexibility years ago with compression ratios. My stock 69 428 had the smaller dish in the factory pistons.

__________________

65 Tempest, 400, TH400
86 Fiero SE 2.8