Would My Car Benefit From 1 3/4" Headers?

90Indy · 10-02-2009, 02:16 PM

I am planning on pulling my 1 5/8" full tube headers and I am wondering if replacing them with 1 3/4" would result in any benefit? I am running a forged 383, superram, custom tune and 8# boost etc. I know the answer would be "yes" except for the fact that the heads are AFR 180 Eliminators. I know the heads are small and why they are installed is a whole other story. At this point I am not going to buy larger heads.

I don't want to spend the $$ if there would be little to no benefit. At this point I think the heads are well matched for the header size and a larger header will only move as much air as the heads can move. I have not had enough experience with this type of setup to make an informed decision.

If somone has real world experience or a suggestion on where to go to do some research I would appreciate a response.

Thanks,

90Indy

mnstrlt1 · 10-03-2009, 02:18 PM

i wouldn't bother with the 1 3/4" headers. they will result in a gain (minimal). At this point you've got a decent combination, and it's not the stock manifolds so the results wouldn't be so dramatic.

*if* you choose to get headers, you might as well toss the 1 7/8" headers on there. You might even be surprised that you might loose on the bottom-end only to pick up some on the top end.

The larger primaries certainly help in a boosted application; however. This is because the blower doesn't have to work as hard to get the spent gasses out of the chamber. Soooo, in a blower application the size of the primaries certainly do make a much more noticeable difference. regardless of the heads, they can benefit from larger primaries.

I think you'd be happier with cat-eliminators, to free up the flow a bit. You can get a shop to make up a set of eliminators that can be swapped in for "off-road" use. Probably gain a few horses that way.

Brand-X · 10-05-2009, 12:25 AM

[quote=*if* you choose to get headers, you might as well toss the 1 7/8" headers on there.[/QUOTE]

does anyone make off the shelf 1 7/8" headers for the C4? I'm familiar with some custom stuff but it is pretty pricey.

mnstrlt1 · 10-05-2009, 04:57 AM

Quote:

Originally Posted by Brand-X

does anyone make off the shelf 1 7/8" headers for the C4? I'm familiar with some custom stuff but it is pretty pricey.

Well, I recall talking to Merle (Exotic muscle), and he mentioned to me that he DOES have them available. Of course, the price is about double the price of his "typical" headers... keep in mind that his collectors are much nicer (I do beleive he uses Burns or equivalent collectors) on his 1 7/8" headers. They are also in stainless steel.

Other than Exotic Muscle, I don't know of another vendor (nor have I looked).