[TransAm 474]

Hi, we are building a 1970 YZ Ram Air 3 400 in a 1970 Trans Am for a customer. He wants it to remain basically numbers matching and stock as far as block and heads go, but stated he would like maybe a bit of a camshaft upgrade to get a little more out of it, but nothing too radical.

It is a YZ block, stock #12 Heads, factory rods, and cast "8" eyebrow pistons with no markings, but it appears the bore is .020 over when measured with a caliper. The pistons appear to be around .040" in the hole as well. The camshaft that is currently in it is unknown. The only stamping I can find on it is the letter "A" stamped in the rear on the camshaft, along with "MAP" stamped in the rear as well. There is nothing else anywhere on it, front or rear. I would like to talk him into letting me replace the pistons with normal Flat Tops, and try and get it atleast close to zero deck, either with the pistons, or having the block decked. I am going to also try and talk him into letting me replace the factory 50 year old rods with a better set of 5140 rods, this build doesn't need 4340. Compression should be up around 10-10.2 I believe, if I were to do those upgrades, and I was thinking about using the Crower 60916 camshaft, but then I suppose that would require an adjustable valvetrain?, so the cost just keeps climbing for him. This is just a street restoration project, so he doesnt really want to go all out with this build, which is understandable, although he did say he wouldn't mind a few upgrades. We are also thinking of buying the carb kit and Jets/Rods from Cliff to build the Qjet, and maybe have someone put the factory Points distributor on a machine and set up a custom curve for it.

So my question is, what would be a good camshaft for this application on Pump Gas without running into problems with pinging and detonation, while using the stock, non adjustable valvetrain. The valve springs will be Crower 68404. I like the idea of the 60916, just wish it didn't require an adjustable valvetrain.

How much compression do you think it has in its current configuration, and what camshaft would you recommend for it with its current parts and compression?(just in case he wants to use what he already has.)

Thank You