ping at hard excel

External Since: Dec 29, 2006 Posts: 1

i have early model 454 in a gmc pickup. I run premium gas. I have a
compression ratio of 10.50/1 my cam is advanced 4 degrees but no
matter how I have the timing it pings at hard excel. I have almost all
spec for my cam size( intake lift 0.475in exh lift 0.500in)( intake
duration 264.0 exhaust duration 274.0) my piston are 230 domed sealed
power fordged

External Since: Sep 01, 2003 Posts: 49

Degree it in straight up or retarded 2 degrees this will reduce your
dynamic compression ratio. You also should be able to see the difference
on your cranking compression it will be reduced.
Stan

hot-454.TakeThisOut@Hotmail.com wrote:
>
> i have early model 454 in a gmc pickup. I run premium gas. I have a
> compression ratio of 10.50/1 my cam is advanced 4 degrees but no
> matter how I have the timing it pings at hard excel. I have almost all
> spec for my cam size( intake lift 0.475in exh lift 0.500in)( intake
> duration 264.0 exhaust duration 274.0) my piston are 230 domed sealed
> power fordged