Pinging B$@&%@rd 440!

[a70duster]

Did you confirm that the timing mark's TDC correlates with the piston's TDC?

 

[mopower440]

Did you confirm that the timing mark's TDC correlates with the piston's TDC?

yessir

 

[Killer6]

I will have to check as i cant remember. I BELIEVE i am using the standard heat range plug for a 1975 new yorker with 440 as thats what the engine came out of originally.

That's an RJ14YC, ....or NGK's equivalent, waay too hot for hotrodding. 440 I put together over 25yrs ago running 10:1 with the smaller 280°/.474" Purple Shaft, 1.875" headers & 3" exhaust, cold iron intake 750VS Holley,..... happy @34° total........and that's with a MP electronic dizzy,...notorious for a fast curve....

 

[watt340]

My guess is that your timing mark on the harmonic balancer is off. With a piston stop, bring the #1 piston to Top Dead Center, then check the timing mark. I bet the elastomer has allowed the outside of the balancer to rotate.
34 degrees of total timing shouldn't allow spark knock.

 

[1968rt]

oh man that sucks. I have been getting ready to buy some 84cc aluminum heads for this thing and thats going to raise compression even more and probably make this worse! Unless being closed chamber would help for some reason or other?

Higher compression will be fine if you have quench. Are the new heads closed chambered?