Quote:

I'm not sure if anyone has covered this question. I have an original 69 440 magnum factory pistons, etc. (Grandmas 69 Charger R/T) If I pulled the 906 heads off and put 440 source heads, on would there be any valve to piston problems, large compression ratio changes, or other issues. I was considering this for the weight savings, factory look, and a bit more hp. I have a mopar m1 factory style alum. manifold also. Has anyone done this?



I have not done this.

My opinion is that it should work well. If the heads have 80 cc chambers, and the motor does indeed have its original 2.034" CH pistons, you will be at an honest 9.8:1 compression ratio (0.040" gasket). I believe that the actual compression distance from the factory in an uncut block with these pistons is about 0.050" in the hole. Someone please correct me if I'm wrong.

On my 440 with factory 915's with this exact piston and a stockish cam (MP 272 w/.455" lift) had about 0.25" p/v clearance on the intake and I could not even find the exhaust valve.