I'm gearing up for an injector change and with that, I will install the comp 910's more from a proactive maintenance aspect than as a requirement as a result of boost in excess of 40psi. I'll be targeting 35-40psi with the stock 38R to optimize it's efficiency. Regarding spring pressure, I will be targeting either 1.80" installed height yielding ~110lbs seat pressure or stock 1.833" for ~99lbs, haven't really decided yet. For reference, factory springs are 71-79lbs and reputedly weaken from there.

At any rate, the piece I haven't been able to nail down is if stock pushrods are sufficiently strong for these spring pressures or not. I'm inclined to buy a new set of stock pushrods for $70 and go with it but, I read many folks spring for the $220 Smith brother pushrods. Some say the new pushrods are a little shorter than what came from the factory for better geometry. Some say stick with the stock to function as a sort of fuse. What say you?

 

I continued to run the original stock push rods after my 910 swap with no issues. I repeatedly flirted with the 40 psi and rpm red lines at the track and dyno. They still held their own in this hostile environment. My springs were shimmed .030" across the board.

 

Good to know. .030" should yield 1.803" which would be about 110lbs I am shooting for.

 

PM me if you are interested in using my McTool to do the spring swap.