[wickettoby1]

If you want to change to an aluminum head you only have a few options that will match the valve notches in youre current pistons. You probably have a flat top or slightly dished piston so youll need to use an "open chamber" head to keep the compression ration pump fuel tolerant. I believe trick flow power ports, edelbrocks or the Chinese speedmaster are youre only options. The A429's had the correct valve layout but i believe the chambers were much smaller.

The valvecover profile/location wont change or at least wont change much going from a D3 to any of the above options. Usually its the rockers that determine how tall the valve covers need to be.

Can you lower the engine in the chassis to gain a little heater box to valve cover breathing room?

 

[wickettoby1]

A static compression ratio of 11.8 is quite high but you’d have to run the dynamic comp #’s to see what that would be with you’re current cam. You may have the option of re-notching the pistons and using an AFR head which I believe are offered in 75 and 85cc chamber volumes.

I figured moving the engine location would/could add interference issues with the oil pan or headers or frame.

 

[wickettoby1]

My first suggestion was gonna be to accumulate parts as $$ allows and build a new engine then swap and sell youre current engine.

 

[wickettoby1]

Without a backup engine ready to go you better think long and hard about heading down the nitrous road. Even if your timing and jetting is on point a failed component (solenoid, fuel pump, retard box) can really ruin you’re day. Just my $.02