View Single Post
WERK I WERK I is offline
Forced Induction Junkie
WERK I's Avatar
Join Date: Jan 2003
Location: Wisconsin
Posts: 3,291
Originally Posted by AFM744 View Post
I cc'd out my combustion chamber and piston and it came out right at 7.0. I put in my custom JE 8:1s and they cc'd out to 8.0 even with the twin-plugged combustion chambers. I have also heard some say the CR is not even 7.0 but lower. But the /66, /68 and /69s all have the same heads and pistons. At least I think the heads are the same; 5 of my heads have 5/91 DoM, but one is an '88 or '89, and it has slightly different shaping of the spark plug recess. Otherwise identical.
Check your exhaust port size as I think the C2 Turbo exhaust ports may be 2 mm bigger than the earlier 930/6x series of heads. M30/69 exh 36mm vs. 930/6x exh 34mm. Intakes are the same.
'85 930 Factory Special Wishes Flachbau
Werk I Zuffenhausen 3.3l/330BHP Engine with Sonderwunsch Cams, FabSpeed Headers, Kokeln IC, Twin Plugged Electromotive Crankfire, Tial Wastegate(0.8 Bar), K27 Hybrid Turbo, Ruf Twin-tip Muffler, Fikse FM-5's 8&10x17, 8:41 R&P
Old 12-08-2008, 04:21 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #36 (permalink)