[Diy_efi] Timing table change needed with CR increase?

[Robert W Hughes]

> With the 90s LTx variety of 350, GM defied accepted rules by altering
> the CR on a particular engine/head combo solely by increasing the head 
> gasket thickness. OEM GM gasket choices were a pre-compressed
> .029" and .049". In the process, the quench distance on typical OEM
> assembled engines could exceed 065". That generation of SBC can be
> considered to be respectably knock resistant, PCM ignition retard
> capability notwithstanding.

Back in the old days Chevy used to ship the hyper 327s and 409s with two 
headgaskets per side, cut an advertised 11.25:1 down to about 10.25:1. I 
seem to remember these as being the thin beaded steel gaskets.

-- 
Robert W. Hughes (Bob)
BackYard Engineering
29:40.237N, 95:28.726W or perhaps 30:55.265N, 95:20.590W
Houston, Texas "The city with too much Oxygen"
rwhughe at oplink.net