What are typical cam specs for a tunnel ram on a small block Chevy?

Answer 1

This is a broad question, and technicle, but I will try to help you, as much as I can. First off, unless this is a car for show only, then this is a pretty serious commitment. A tunnel ram, is for high rpm use, only. They DO NOT run well at all, in the cold, or even on the street. I can remember having to take a butane torch, and heating up the runner, just to get it to start, at 35, to 40 degrees. And, they backfire, flames, out of the carbs, a lot. And rain driving is pretty much out, due to the enormous scoop you are probably going to have to run. I remember spending $150, plus, just for the linkage to run my 660's sideways on the intake, which you have to do, to keep fuel to the float bowls, by the way. You should install 2 electric race pumps, and while you are back there, you are going to need super low gears, cause you will have to spin that thing 7000rpm, to reach the power band. A steel crank, and forged pistons, are a must, along with a set of DART., or other aftermarket head. You are going to need at least 4000rpm, out of your stall converter, and a manual valve body, would be a good idea. Having said all of that, Crane makes two cams that would work well. CC280anc, and the cc290anc. Either will make that motor scream. The first has .518, .536, on the lift, and 280, 290, duration. It has a 108 lobe center, so it will idle rough, but, it will make power allthe way to 7000. The 290 version, is more nasty, but has a higher rpm band. They both are dual patern cams, which seem to work better in this situation. They both have aggresive valve timing so remember to check valve to piston clearance. At least .120 on the chase valve. These are both flat tappet cams, but are both nasty enough to make this thing run. Most people "overcam" their small blocks. That is why I do not feel a roller, is needed here. Roller rockers, 7/16ths studs, and a stud girdle, are a must to spin those type of rpms. Also, I have found over the years that the holley 660 center squiter works best in a two carb situation. That have been said, from experience, I can tell you, you can go just as fast with a single 4 barrel. These days tunnel rams are pretty much for show....