Sorry to dig this up, but wondering about anyone using these headers with EQ Magnum and/or MP R/T heads, not just the standard ones.
An OEM head has more material around the bottom of the port and allows for the big port LA headers/manifolds to seal. The EQ and MP R/T head doesn't have the same casting and the heads stop just below the port leaving little to no material to seal the large port LA headers/manifolds.
I read numerous yrs ago that the ports were different but that's a bunch of baloney. I don't know who started that but they sure didn't know what they were talking about.
The exhaust port are different. They match closely to the LA 318 ports, but are significantly shorter than the LA 360/340 exhaust port. And with the R/T and EQ heads, they don't seal. Picture here - 5.9magnum questions
