Help me diagnose my miss over 4500rpm.
I'm gonna go through my ignition before I get too crazy worried. But yes, that's one of the next steps if necessary.
Cley
You already did the ignition; what did I miss? Oh the looking good plugs? Mine are about 100,000 miles old,installed in 1999.They look good too.
You said bit of a cam and 100psi. I checked Martensville elevation@ 2300ft.
For the heck of it, I threw a 268 cam into an 8/1 360, at the Wallace calculator,and it got 116psi.
Either your cam is way bigger than a 268, or it's a slow-azz 268, or the engine ain't an 8/1, or you are at higher than 2300ft.
Or the engine is hemorrhaging pressure .
If I drop the Scr to 7.8, then
Static compression ratio of 7.8:1.
Effective stroke is 2.61 inches.
Your dynamic compression ratio is 5.96:1 ............................... 5.96
Your dynamic cranking pressure is 99.00 PSI.
V/P (Volume to Pressure Index) is 78....................................... 78
The low pressure is not cause of your miss, but whatever is causing it could be... like bent or sticking valves, or more specifically worn out or broken valve springs. Good luck.
