Is Quench Required?

RustyRatRod said
Here's the same info on the engine in the car NOW. It has the crappiest open chamber slant 6 head ever and the piston is .180" in the hole and it doesn't spark knock not one bit.

Static compression ratio of 10.6:1.
Effective stroke is 3.04 inches.
Your dynamic compression ratio is 8.07:1 .
Your dynamic cranking pressure is 162.21 PSI.
Your effective boost compression ratio, reflecting static c.r., cam timing, altitude, and boost of 0 PSI is 7.95 :1.
V/P (Volume to Pressure Index) is 83

Thank you. That provides a little bit of relief. What type of fuel do you use in the current combo?

Newbomb Turk said
I don’t use “dynamic” compression ratio because it has to to be calculated with RPM and load.

You are better off using effective compression ratio because once the SCR and IVC are set it never changes.

I’m saying that dynamic compression changes, hence the word dynamic. That Wallace calculator (and all the others I’ve seen) never tells you at what RPM it occurs. If it uses VE in its calculation than it’s only at that VE where it’s correct.

Inlet air temperature isn’t included because that affects DCR as well and some other things I’m forgetting.

The math I use for picking cam timing uses ECR and not DCR.

Thanks. I'm only using it for comparison purposes. Basically comparing how changes in deck height, gasket thickness, etc. impact compression and cranking pressure.