exhaust port shape

[terry]

hi folks i was helping a friend install a 408 magnum stroker with mopar aluminum heads on it now the exhaust ports are square BUT on the TTI 1 5/8 step headers that he bought the flange ports are round on the headers. did they give him the wrong ones? his p/n is 340aw2c3 which seemed to be for an A body with w2 heads? this just doesn't look correct

 

[Map63Vette]

I think all of their tubes might be round at the flange. I bought a set for my 5.7 hemi swap which is square ports and the headers are round at the flange. They cover the entire port (the circle fits the square inside okay), but I agree it's a little odd.

 

[RedFish]

A smaller diameter that would create a step could cause problems. A diameter larger than the port shouldn't be an issue.