Which heads are best

moper said
The smaller cam will run the brakes, but won't work because of the pistons. The larger cam will work with the pistons, but won't run the power brakes.
I agree with Yellow about D. Hughes and his opinions.
None of this is hyperbole unless everything is hypothetical. We have real specs for the lower end and the OP's goals. Unfortunately those "givens" now dictate the top end to work within the provided parameters. You need to lower static, giving up any chance of quench in order to be able to run a cam small enough to run power brakes and run on available pump fuel. IMO - the "right way" would be replacing the pistons with dished, rebalancing, and running a modern, closed chamber, aluminum head. I steer clear of Magnum based stuff because the valve train costs are higher and the return on investment over an LA-based head marginal (by my opinion).
If you don't want to redo the lower end, either run a stock head (the chambers will be larger than 74cc as cast...) and a thicker gasket to end up around 9.8:1 static, or run the open chamber RPM which are no different than the closed chamber except for the .100" deep chamber milled out of them. There is no power difference you will notice between the two models of LA based RPM.

I've seen more around 68cc from the stock untouched 360 heads I've cc'd. I wouldn't count on them being 74cc unless heavily worked.

yellow rose said
Like I said, guys get all bent up over BULLCRAP like DCR and running power brakes and a cam that idles too rough etc. Most of that is BULLCRAP as well. If you are running a carb and you can tune, what is considered a large cam will idle at 900 RPM. It's all in the tune. There are men who bum around on these forums, like thumper dart for example, who specialize in carb tuning and they are Chrysler guys. Deal with them.

As for power brakes, I won't ever have them on a muscle car. I learned that in 1981 on my 1972 Demon. Even with a stock cam it never stopped well. My dad was friends with a guy who owned a wrecking yard. He turned me on to the CORRECT sized manual master cylinder and the car stopped better than new. Just converted my 1973 Dart Sport to manual. Both had disc/drum.

You are running 408 cubic inches!!!!! Think about that! 20 years ago that was BIG displacement. What was a large cam in a 340 is a pea shooter in a 408.

The last thing I want to say is about compression. I love it. I do everything I can, to squeeze every single bit out I can for the application. BUT I will NOT compromise combustion chamber modifications at the expense of compression. I mean I will not keep .5-.75 more compression if it compromises air flow or chamber design. You can mentally beat yourself to death over picking the fly poop out of the pepper.

I can take or leave power brakes easily. I don't think they're necessary on a 4000lb truck, much less a car that weighs several hundred less and that's one I can't see why it'd be a necessity. You should have brakes that don't suck- the late model discs with 10" rear drums is a decent enough combo.

You forgot "low-end torque" like a 2900lb car is going to see a huge benefit from making over 300 ft/lbs at a 500RPM idle most couldn't tune out of it rather than making more at higher RPMs. Doesn't even make sense for a medium duty truck that'll haul all day long...