Header tube sizing 2?

Dropping the 557 stock port a head motor into the ol stang. I'm having headers made. What do you guys think for primary size? 2 1/8 stepped to 2 1/4 or 2 1/4 straight?

id say 2 1/8 stepped to 2 1/4 would be great

Thanks Nick

I agree 2 1/8 to 2 1/4 steep always works best.

2 1/8 strait is plenty IMO, I haven't seen hugh gains for the stepped stuff and don't feel for a regular bracket car its worth the agrivation. I will say spend time on the collectors, you can get big gains from them.

Put 2-1/4" on it......I see little if any down side with the "Seth" engine. Plus, if you spend $s for the smaller step heads and later put some domed pistons & a cam in that deal you'll be sick that you need bigger headers to avail yourself of the better engine package.

Lem Evans wrote:Put 2-1/4" on it......I see little if any down side with the "Seth" engine. Plus, if you spend $s for the smaller step heads and later put some domed pistons & a cam in that deal you'll be sick that you need bigger headers to avail yourself of the better engine package.

Yes I failed to mention to keep in mind that the future may call for more of a "race" set up.

No....it's 3 for the little step deal and 1 for the 2-1/4".....you gotta run the tow truck header

I made a set of Shane Diesel series headers for the DD, don't make me explain that one either, lets just say they have "girth"............

Shannon,

I ran stepped 2-1/8"-2-1/4" primaries w/ 4" merged collectors built by the late Tim Murphy of Fab-Shop Headers.

They worked great.

If you are going to use the same headers to step up your program in the future, I would lean towards the "bigger is better" thought. I built a set of 2-1/4" stepped to 2-3/8" with 4-1/2" collectors for my 605 A-head. Later, I installed a set of 5" collectors, and it went faster...
It has all of the low end power that I can use.
Yeah..I know there are all of the formulas out there to determine the "correct" size. That is just my opinion.
I guess that will be a good test for me to perform on the dyno....drag out several sets of headers, and back-to-back test pulls.
Keith

I have a set of junk (sorry Coug) 5" collectors I may toss on mine as well this winter, I could stand to kill some bottom end lol

Sure the 2-1/8 to 2-1/4 will "work" and work well. It's that the big stuff will work same or better and allow room to grow the engine package.

I have 2" on my 572 I built my self on edelbrock heads and it made good power . I'm not a big believer in large tube , keep them as equal as you can.

Thanks for everyone's input! Happy turkey day!