Derek 357i

iTrader: (1)

I just bought a Shoenfeld 1 3/4" primary weld up header kit and flanges to make my own headers for my car. The steering gear location does not allow me to fabricate conventional headers. What I am kicking around are some tri-y headers with equal length 1 3/4" primaries 2 1/4" secondaries into 3" true duals with an X pipe. I am planning on grouping the cyls 1&5, 3&7, 2&4, 6&8.

The layout would be roughly 10" primaries merging into the Y. At the bottom of the y is will a flange for the 2 sections of 2 1/4" which I will be able to route around the steering gear keeping equal length. At the end of these (roughly 20") will be a Y merging them into the 3" collector with a flange. The 3" exhaust will be about a foot long before merging into the X. After the X the 3" duals will run parallel to the back of the car where they will flow through a Spintech Dual 3" in Dual 3" out muffler (to keep the factory look.) From the 3" collector flange back, the system would be all one piece (welded), as it an Indep. Rear Susp. car so the exhaust goes underneath everything the whole way back.

Any thoughts or suggestions would be greatly appreciated.

88SS LS1

iTrader: (9)

Have you looked at how John Bzdel exhaust is setup on his Monte Carlo?

Derek 357i

iTrader: (1)

I did, I just don't have that kind of room for running primaries. His headers look GREAT BTW.

RickyD

I would highly recommend reading all of the info you can find at headersbyed.com There is quite a wealth of knowledge there. Not a lot on actual construction but a lot on performance design.

parsonsj

Here's a useful link to some custom header construction ideas as well:

http://www.carcraft.com/howto/0304_head/index.html

John Parsons

Pro Stock John

iTrader: (34)

What about Vette or F-car shorty headers?

I sold a set of LPE prototype headers to Valvegod once.

John B

iTrader: (10)

What exactly are you working on? I just finished fabricating a set of true equal length headers (+/- 1/16"!) using 2-3/8" diameter tubes w/4" collectors that fit inside of the frame of a lowered C2 BBC that fits like a glove and I had massive steering box issues at first. After building these I am convinced anything is possible

Derek 357i

iTrader: (1)

I have tried both the F-Body and Y-Body exhaust manifolds. (I was going to be lazy and just try to get the car on the road and worry about headers later.) I have the engine too far back for the F body, and both the F-Bbody and Y-body dump the driver's side exhaust tube right into the steering gear.

John, I am working on a 1984 BMW 318i. There probably would have been plenty of room if I hadn't modified my dry sump oil pan to put the engine as low in the chassis as possible. I'll try to get a shot of the steering gear and send one to you. I am sure if I had your fabrication skills a solution would be readily apparent, but unfortunately I am not there.

Here is a link to a few low res pics.
http://www.bimmerforums.com/forum/sh...hreadid=132213

John B

iTrader: (10)

Flattery will get you nowhere!!! I'll wait for the pics.

LS1swap

Did you ever consider two passenger side manifolds? It would change the angle of the collector.It was one of the options I was thinking about when I did my swap. didn't work for me and I had to fabricate a custome manifold as well . but a thought..... Just out of curiosity how much is the Shoenfeld 1 3/4" primary weld up header kit ? Did you know GM sells a flange kit for the ls1 pn 12480130. They were $17 a side wholesale a side.

Derek 357i

iTrader: (1)

LS1swap, I didn't consider two pass side manifolds. The passenger side manifold didn't quite fit on the pass side either. I may go take a look at it and see, but more than likely I'll do the headers. I really want to keep the car balanced, so having headers on there would help in that aspect as well.

The Shoenfeld 1 3/4" tube kit was $117 delivered including 2 3" weld on collectors. I bought those flanges from gmpartsdirect.com for something like $12 each. They are very nice.

88SS LS1

iTrader: (9)

I was wodering where you got the shenfeld kit from

Derek 357i

iTrader: (1)

http://www.schoenfeldheaders.com/

88SS LS1

iTrader: (9)

Appreciate it

LS1swap

I agree that the headers will be much better if you can get them to fit. My manifold system probably leaves allot to be desired. I basically copied the V6 set up that my car came with. With the Fiero and the V8 the space is so limited that I couldn't do what I wanted. It is four short runners dumping into a lager pipe. I am sure I am loosing some horse power because of it , but on a good note at least now I have a few to spare now . I have some new ideas now and maybe someday I will redesign it. Thanks for the info!