i am going to make my engine compression 10.9-1 will i have problems with fuel . knocking and pinging?

 

On iron heads, yes, pump gas would be a problem. Aluminum heads, you'd still be on the edge of what pump gas could handle well. 10-1 would be my max... even then you'd have to pull timing and add a bit of fuel to resist knock I would think...

 

According to what I have read 11:1 is max for Alumnium heads, fuel injection and premium pump gas. Just make @#$%@% sure your engine is always properly tuned , plugs, cap, rotor, wires, etc.