I am building my 67 Valiant project with my kids. It is intended to be a budget street and strip car.

Engine is a 76 440
Holley SD intake
Holley 750-3310
Fenderwell Headers

Engine is essentially stock. I have a MP .474 Cam that I am going to run, even though it may not be ideal. Windage tray, double roller chain etc. Nothing special other than intake, exhaust and cam.

Eventually I would like to up the compression and run better heads.

My question is, what actual HP benefits am I likely to gain by home porting the heads which are 452 castings? I have done a set or two before. Fairly good at it, but not perfect of course.

Is it worth the effort? Based on my combo, what HP increase is likely assuming I do a good job?

Thank you for your time.