Here is the situation...

I want to put the biggest cam possible into a set of stock d3 closed chamber heads. they have the non-adjustable valvetrain. I do not want to spend the money to upgrade the the adjustable type. I traded for this 460-c6 combo and I have no money in it thus far. It came with an old streetmaster single plane intake (I heard it sucks?. I am trying to go low-buck.

So, what is the biggest possible cam I can stick into that thing without breaking anything?

 

That's a new one for me. Call one of the cam grinder tech lines and they can answer you question. I'd be interested in what they recommend.

Don't expect a miracle increase in performance as you're looking at a low compression engine.