Re: Need Cylinder Head, '34 8. What Yrs would be Interchangable ?

Posted by flackmaster On 2020/5/18 7:47:04

You are overthinking this unless you are OCD or have some Pebble Beach judging standard you are striving for, or performance specification being held to.

Low compression heads were most often used on export cars (educated speculation - e.g. places with poor fuel quality), and high compression heads optioned for slightly better performance objectives. The difference in compression is fairly minor, given the quality of fuel today, and performance expectations.

The only "dilemma" to be resolved is to understand the evolution of the heads from 33-39, some of which is presented here (e.g. Packard's switch to aluminum heads in '35, nor have we have not discussed spark plug size, nor the modification to use the 39 head, heater and temperature gauge ports, etc), and make a choice what you want to obtain to get your car back on the road.