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I've been watching this post with interest. You all are correct in the choice of cam. Hyd. Roller profiles are more aggresive than a solid ft. However, I think the post while valid, isn't going after the most important item :: cyl pressure. It is very difficult to develop needed cyl. press. The planned motor, w/o the cam is suspect to me. Static compression ratio needs to go up. With alu. heads to 12 to 1.
I had an iron headed 383 at 11.7 static cr and moderately aggressive cam with quench @ .040 that ran w/o any detonation. But it was still underpowered up here.
Consider that we lose an average of .9 sec on a good day of quarter mile times because of air density/cylinder pressure when compared to sea level. Many times our DA is 8000-9000 ft. Generic power loss is on avarage 20%. No cam profile is going to make that much up.
So to plan this out correctly IMHO, Up the static compression ration to 12/1 and .040 quench and use that roller you have posted. My experience says you will still be fine on detonation AND you will have a build that will scream.
I will also add that that cam seams a little small. I've now got a Solid ft that is much more agressive than whats posted in a 470.



That is right as the cyl pressure is the bottom line that all of this effects and at sea level I would not push it mover 200 if you want to run on pump. In fact I like to keep it around 180 for pump at sea level. I am not sure at you elevation. But I can say at sea level I would not hesitate to run 11.5 comp with aluminum heads and quench as with the right cam you can run on 92 or 93 pump. My sons 400 has Eddy RPM heads and I cut them to get his 400 at almost 10.8 and it does not have good quench as his pistons are down about .023 and it has the .039 head gaskets. But we run 38 total timing with no ping at all. Aluminum heads can usually run about 1 point higher in comp. But you need to watch where the cyl pressure comes out. A good cam company can help with that. Good luck , Ron