Ecm and heads question

[dusterbd13]

Ok, so im close on the 3400 miata.

have the engine on the stand for gaskets. Im debating on porting the heads while i have it out and apart (replacing the head gaskets as preventive maintenance. Anything i need to know?)

with a cold air intake, 3500 upper plenum and alero throttle body, long tube header and free flowing exhaust. Would i gain anything to justify the effort?

also, i have a 2001 impala harness and ecm as well as the 04 Buick rendezvous ecm and harness are. Which should i use, and what all besides the engine and trans sensors is the computer looking for? This is a race car, so no worries about gauges/emissions. 5 speed as well, and i will be sending tbe ecm out (whichever one is simplest to use) to get it tuned. So which one do i want to use?

any otger cheap/free power mods i can do?

[1QUICKHATCH]

Give the bowls a quick clean up, deshroud the valves a little (look at the 3500 chambers and you will get a better idea of what to do!) And install some 3500 valves if you have it in the budget!

I don't think that there is much difference in the ecms, you will have to have the vats deleted and the codes for auto trans and probably a few others.

[dusterbd13]

Definitely going to look at this.

what k8nd of gains should be anticipated with the headwork (3400 valves. Bigger valves not in budget)