does anyone know what the compression is on a stock 454 vortec
09-02-2010 12:26 AM
Carnak holds the envelope up to his turban and closes his eyes. He is still for a moment, then says "The young man needs to know the SCR so he can choose a camshaft"
The audience erupts into applause, hootin' and hollerin'.
The Vortec 7400 came in a L21 and L29 configuration. en.wikipedia.org/wiki/GM_Vortec_engine
The L21 is a regular peanut port version casting #10114156, 1991-up 454 Open 118cc gen.V (like 236's) while the L29 Casting #12560241 1998 -up Closed 100cc Vortec 7400 had the larger ports with heart shaped combustion chamber and ski jump in the intake port. I don't know what the compression rations were however the combustion chambers on the heads are sure different.