I would like to know what the dynamic compression is for my 406 sbc. I know its not an LS1, but the gen1 engine section isn't very active. I came up with 7.9 dynamic and about 10.1:1 static, but I am not sure that is right.

The motor is a .030" 400.
4.155" Bore
4.155" head gasket bore
.041" thick head gasket
3.75" stroke
64 CC combustion Chamber
16.2 CC dished piston
piston will be about .005 in the bore.
5.7" rod

Here is what my cam card looks like.

Intake Exhaust
Valve Adjustment 0 0
Gross Valve Lift 0.541 0.544
Duration At 0.006 Tappet Lift 284 296

Valve Timing At 0.006
Open Close
Intake 36 68
Exhaust 82 34

These Specs Are For The Cam Installed At 106 Intake CL
Intake Exhaust
Duration At 0.05 240 246
Lobe Lift 0.338 0.34
Lobe Separation 110

 

I will calculate it later tonight if someone else hasnt, ahve class and football til 6.

 

Here is what I came up with. Static 10.447:1. Dynamic 8.177:1. Hope this helps.

 

thanks for the help 1989GTA

 

Scr 10.2149997664489
Dcr 8.00086697117901

 

Thanks JRP.