Re: ping at hard excel

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@[EMAIL PROTECTED]
 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