[blykins]

Where do you want the peak to be?

I had a Comp 248/254 solid roller in a 428ci FE. It peaked at 6500.

I also had a custom hydraulic roller in a 445ci Windsor, with a 250/250 duration. It peaked at 6000, but I was experiencing some valvetrain issues.

I would think with 482ci, that you could get away with the 252 cam and not have to use any exotic valvetrain pieces like titanium retainers, heavy springs, etc.

With a lighter car, a 5-speed, and large displacement, I'd go for the larger cam. I would imagine your peak hp rpm would be around 6000-6200. I think that's a good range for a hydraulic roller.

With the smaller cam, I guess your peak hp rpm to be around 5500-5700.

Either cam is going to give you good performance and with a lightweight car like a Cobra, you can live with a little wilder cam. Depending on what the advertised durations are, the larger cam will also lower your DCR, which may allow you to run a cheaper gasoline like 87-89 octane.

Be sure to recheck your P/V clearances. Even if both cams have the same lift, the valve timing events will change the results.