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?
I gotta start this response out with "Your results may vary!"
I made two major changes to my Challenger "waaaaay back when" not too long after I bought it in the mid-90s:
- I swapped a set of stock rebuilt 906s for a set of 452s that had 2.14"/1.81" valves and a LOT of hours of my time porting them in a really cold detached garage over the winter; IIRC, the 452s had slightly smaller chambers that bumped the CR from about 9:1 to 9.5, too
- The same time I swapped the heads, I also replaced the stamped MP "heavy duty" 1.5 rocker arms with a set of Crane iron 1.6s
First time back at the track with the heads & rocker changes, the car picked up 6 MPH and dropped over 1/2 second in ET.
Oh, and it still had the little MP 272 (222* at .050") / .455" hydraulic cam in it.
