I was only looking at 1-7/8 cause that's what was recommended on mopar's website for my motor. I just didn't know on size or what headers. I've been looking at dougs cause the autozone deal. Tti cause they make a 1-7/8.
A long as I've seen the TTI/Dougs comparison/debate, I finally looked the Doug's up. It appears that they are 1 5/8" all the way! The 1 3/4" step on the TTI's do make them more versatile than straight, essentially a 1 3/4" header. Properly spaced/sized, the step helps scavenging/flow and are used on a variety of race headers. I've heard of Stock eliminator 350 Chevies actually start out around 1 1/2", but stepping up 2 more times! Straight 1 5/8" pipes could be considered a restriction for street/strip or race applications. My opinion is that 1 5/8" would be a restriction and 1 7/8" would be too big. I had custom 1 7/8" headers on my 360 W-2 bracket Challenger weighing 2,800 lbs and running as fast as 10.22 @ 131in the '80's & '90's. But I didn't even consider going bigger.
