Which head/combustion chamber is better for performance? Speed master aluminum LA or aftermarket magnum iron head?

StreetSleeper said
Can one assert that the stock magnum heads 5.2/5.9 are base level and then the R/T next level?

I want to say I have heard that the cast iron R/T's were better than the old EQ's which were better than OEM. So that is how I would rank them.

StreetSleeper said
Should the next level only be used for stroker builds?

For a stroker build, I would guess even an R/T head would limit them without some work unless the cam was pretty mild.

For a stock stoke build, I would say the EQ's or R/T's would be fine depending on the cam.

For a stock Magnum build, I think even the current EQ's are fine as the cam is the bottleneck.

But I am not someone that would give advice on these things so they are just my guesses.

StreetSleeper said
How would that cast iron R/T head (intake runner 179cc -??) compare to the aluminum magnum head?

No real idea on that. If the Speedmaster is a ripoff of the Edelbrock aluminum head, I would guess the Speedmaster would have better ports. But complete speculation on my part.