Dragon Slayer
Well-Known Member
I think some of the approach is wrong when you take 12.5 to 1 pistons in a stroker that has piston CD to support the stroke but also the current block deck, then detune it buy adding really thick head gasket to get compression down. The quench will be much different.
You can mill the pistons to get a lower compression profile, then adjust deck height with a gasket, while retaining a better quench profile. Or find a set of pistons with lower profile.
I bought a package deal too. Standard bore that had been windowed and repaired, but damaged cylinder never fixed. So I had it bored .030 over to take care of the neglected block that had too much cylinder wall corrosion, new sleeve. Lined hone, a critical thing to make sure you get done with hemi's. Mine was not decked as much but my heads were in the 166-167cc range. I had had to mill them some to clean the surface for sealing and wound up around 165 to 166cc. All chambers not as even as you would expect if you cc all 8 chamber. Which I did. Had new bronze sleeves installed along with the valves.
I found a complete rotating assembly with ROSS 10.05 to 1 pistons stroked at 4.15. I had to deck the block slightly to square it, and again clean the surface for sealing. At that point I used head gasket thickness to correct compression, considering how much less I had in the heads. Build back to the deck spec for the pistons. I wound up using .080. (Piston spec used .40 head gasket) So I am right about 10.25 maybe a little higher. With sufficient piston to head and valve clearance. Racer Brown made me a SS-H-44 cam. I went Hydraulic for a street car. I Rebuilt almost all of the parts on this, and I tried to use original were possible distributor, fuel pump, water pump, oil pump, alternator etc...). Luckily I had access to the parts and did this under the guidance of a master builder with decades of experience. I did go the big block pulley and balance route. Otherwise your into a grand for parts if you do not have them. Ran great on the run stand, waiting for my modified Hemi K frame, before a transplant into a 70 road runner. One thing about this approach, I can incrementally raise the compression with a gasket change. .020 will yield about a 1/4 pt compression change, as long as clearance are ok which they are. Thick gaskets are expensive though.
You can mill the pistons to get a lower compression profile, then adjust deck height with a gasket, while retaining a better quench profile. Or find a set of pistons with lower profile.
I bought a package deal too. Standard bore that had been windowed and repaired, but damaged cylinder never fixed. So I had it bored .030 over to take care of the neglected block that had too much cylinder wall corrosion, new sleeve. Lined hone, a critical thing to make sure you get done with hemi's. Mine was not decked as much but my heads were in the 166-167cc range. I had had to mill them some to clean the surface for sealing and wound up around 165 to 166cc. All chambers not as even as you would expect if you cc all 8 chamber. Which I did. Had new bronze sleeves installed along with the valves.
I found a complete rotating assembly with ROSS 10.05 to 1 pistons stroked at 4.15. I had to deck the block slightly to square it, and again clean the surface for sealing. At that point I used head gasket thickness to correct compression, considering how much less I had in the heads. Build back to the deck spec for the pistons. I wound up using .080. (Piston spec used .40 head gasket) So I am right about 10.25 maybe a little higher. With sufficient piston to head and valve clearance. Racer Brown made me a SS-H-44 cam. I went Hydraulic for a street car. I Rebuilt almost all of the parts on this, and I tried to use original were possible distributor, fuel pump, water pump, oil pump, alternator etc...). Luckily I had access to the parts and did this under the guidance of a master builder with decades of experience. I did go the big block pulley and balance route. Otherwise your into a grand for parts if you do not have them. Ran great on the run stand, waiting for my modified Hemi K frame, before a transplant into a 70 road runner. One thing about this approach, I can incrementally raise the compression with a gasket change. .020 will yield about a 1/4 pt compression change, as long as clearance are ok which they are. Thick gaskets are expensive though.
