Trust me...if there was an OHC head that would fit the bore spacing, and flowed enough to consider going through the hell to make it work,..........id make it work.Oh, oh, cut and glue together two 4.6 PI heads and run an overhead cam. You can make it work!
As long as you use epoxy to do itTrust me...if there was an OHC head that would fit the bore spacing, and flowed enough to consider going through the hell to make it work,..........id make it work.
I use epoxy everywhere no doubt. I used it to glue that plate that widens the deck...( it never sees pressure, from water, oil, or combustion). It's only purpose is to hold on a plate, that widens the deck.As long as you use epoxy to do it
But the dyno don't lie. I think it was worth 7hp and 4 ft lbs. On a 3.7 bore the difference would be much less. On a 4.5 bore, much more..
http://www.hotrod.com/articles/dyno-tested-thin-piston-rings-worth-horsepower/
Over the past weekend, I watched some of those Engine Master vids. They a 5/64 vs. 1.5 ring comparisons. The same exact piston in a SBC with different ring packages. The torque required to rotate the shortblock was vastly different. 37ft vs 14ft for the 1.5 mm rings. That's a huge difference. But the dyno don't lie. I think it was worth 7hp and 4 ft lbs. On a 3.7 bore the difference would be much less. On a 4.5 bore, much more.
I think it is not enough of a difference to justify spending money to get custom pistons. If your pistons aren't hurt, then new rings, gapped appropriately. When I slap that junkyard 351 in I think I am running the cast pistons, but may spring for the Total Seal gapless rings. If I put that BD11 on it, it won't make more than 6psi, so that should work for me.
I have custom pistons.
4.5" bore....you are talking big big block territory. 500+ cid stuff. Not exactly relevant.
BTW, the rings in my blower car are 1/16, 1/16, 3/16 for what it is worth. Gap-less second ring.