Header Size at Head!!

Reply Subscribe

Thread Tools

Search this Thread

Jul 30, 2004 | 07:18 PM

polcat

Thread Starter

Elder User

Joined: Jun 2001

Posts: 508

Likes: 0

From: Corpus Christi, Texas

Header Size at Head!!

I am curious to know if any one has had this problem?? Since I am waitng on sending my heads to the machine shop I decided to do some measuring of the exhaust ports on the heads to see if they match my headers. I have a set of C8AEH heads that have never been machined or ported and the exhaust ports measure 1.960 at the widest point, after seeing this I quickly measured my headers which were arround 1 3/4 - 1 7/8. Knowing that your headers should be bigger than your heads this to me would be a performance problem. Has any one seen this or done the measurements????? Can anyone tell me were I can get a set of headers that has a 2" primary tube for a truck?? Not to expensive.

Jul 30, 2004 | 10:32 PM

Scouder

Posting Guru

Joined: Aug 2001

Posts: 2,117

Likes: 0

From: Evanston, WY

I had the same problem with my KCIII heads. No such thing as a 2" primary for an FE that is mass produced. I had to make mine from scratch using FPA flanges, Hooker collectors, and a box of 2 1/8" bends.

-Scouder

Jul 31, 2004 | 07:26 AM

RapidRuss

FE "Freakin Expensive"

Joined: Dec 2003

Posts: 6,461

Likes: 4

From: Smith Mountain Lake, VA

I have either 1 3/4" or 1 7/8" on my 390 right now..I when I get my KCIIs for my 433 build.. Im not sure of the Exaust port size?? So I will probably take and put a 45* angle on the flange and then blend it into the tube, to make a smooth transaction..

Jul 31, 2004 | 09:41 AM

EgoMan

Fleet Mechanic

Joined: May 2004

Posts: 1,436

Likes: 0

From: Montana

Ill probobly just pay someone to build a 2" set to copy my flowtechs. Or maybe sice im spending the mody Ill go all out crazy!

Jul 31, 2004 | 04:22 PM

dinosaurfan

Cargo Master

Joined: Aug 2000

Posts: 2,931

Likes: 12

From: SW Michigan

port/header mismatch

Polcat, you mean 1.96 tall, don't you ? Anyway, the thing to do is to lay a few beats of weld on the outside of the tube, and then grind the inside abit so they will flow smooth. The flow at the top of the port is more important than at the bottom. Lots of FE guys have had to do a little work here, and sometimes some up and down jiggling as well. DF

Aug 1, 2004 | 02:45 PM

polcat

Thread Starter

Elder User

Joined: Jun 2001

Posts: 508

Likes: 0

From: Corpus Christi, Texas

I kinda figured this on the headers, wander if anyone can give me any suggestion on someone that can build me a set of headers with 2" or 21/8" primary. Scouder did you get a bunch of tubing bends and weld them together or did you have to bend them your self??

Aug 1, 2004 | 05:44 PM

Scouder

Posting Guru

Joined: Aug 2001

Posts: 2,117

Likes: 0

From: Evanston, WY

A box of bends in different diameters, and a chop saw. I actually ordered 3 or 4 times from jegs, so I wouldn't end up with a bunch left over. Time consuming work, but satisfying.

-Scouder