Stahl Headers

AceAndrew

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So for a counter point on header sizing, has anyone tried actually talking to Jeff or Jeremy at Ireland?
 

rsporsche

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So for a counter point on header sizing, has anyone tried actually talking to Jeff or Jeremy at Ireland?

i have not - but it could be worthwhile. i spent a lot of time talking to a couple of guys at korman. i found it very informative, and since i have indepth experience with them - i have a sense of trust that they know BMW, and both street performance and racing BMWs - as enthusiasts, engine builders and racers.

my advice to anyone who is thinking about performance with their coupe is to drive it, and first decide what you most want to improve with it. where does it feel lacking to you - the answer of more power isn't sufficient ... where do you want the power? where do you push on the accelerator and NOT get the response that you want? ok - everywhere means go buy a different car.
 

David

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If Im following this at all:

Kormann recommends the 1 3/8" with a schrick 282 cam and 40 dcoes

Tom has 1 3/8 on a 3.5 running DCOE40s and a slightly hotter cam

1 3/8 is going increase bottom end, larger will affect the top end, unless you have a modded 3.5.

What I don't understand yet is, what is the impact of a 1 3/8 on a stock 3.0 with dual weber or zeniths ? Is the performance increase, even on the smaller 1 3/8, only noticable with DCOE40/45 ?
 

TodB

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What I don't understand yet is, what is the impact of a 1 3/8 on a stock 3.0 with dual weber or zeniths ? Is the performance increase, even on the smaller 1 3/8, only noticable with DCOE40/45 ?
This is my question also. Will "strapping on" a pair of 1 3/8 headers to an otherwise stock 3.0 or even 3.5L B34/B35 motor with dual carbs yield any positive results and if so where in the RPM range? I reviewed the Chevy chart and understand the concepts, but is the OEM BMW exhaust (exhaust mani's and dual downpipes) that constricted that headers will free it up? If the headers are that much more efficient, will the motor run leaner? What changes, if any, will need to be made to the fuel delivery once the headers are installed?

I think, with a stock M30 motor, B34, B35, etc., there is potentially more bang for the buck/better performance gain with a hotter cam like a 284 still exiting through the OEM exhaust. You mod the exhaust last after you address the fuel (carbs or FI) and cam and even then, you need to be very careful how the exhaust is configured so you don't lose low end torque which, I think, is what most folks here are after.

That'a my hunch with no data to back it up and I could be totally wrong. I'm just trying to understand better.

That all said, I am considering the headers group buy as well but I have a cam and Weber 38s installed on my 3.3L already.
 

rsporsche

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Tod,

i suspect that you are right - the cam will make a bigger difference than the header alone. together, they will make a significant difference.

let me tell you where i see the rub. stahl is going out of business at the end of the year, from there the 2 primary sources of headers that i am aware of - one is coupeking (expensive) and ireland (affordable). both are short tube, ireland is 1 5/8". so me, the option is to buy the stahl now - i might not install it right away ... but at least i will have it.
 

David

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Tod,
let me tell you where i see the rub. stahl is going out of business at the end of the year, from there the 2 primary sources of headers that i am aware of - one is coupeking (expensive) and ireland (affordable). both are short tube, ireland is 1 5/8". so me, the option is to buy the stahl now - i might not install it right away ... but at least i will have it.

That's where my head is right now too. Seems like at this price I can sell them later and recover my costs if I decide not to use them. But come Jan, this part is gone forever.

I wish Paul Cain or TJ Noto were still around to offer their thoughts to this discussion.
 

TodB

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let me tell you where i see the rub. stahl is going out of business at the end of the year, from there the 2 primary sources of headers that i am aware of - one is coupeking (expensive) and ireland (affordable). both are short tube, ireland is 1 5/8". so me, the option is to buy the stahl now - i might not install it right away ... but at least i will have it.
X 3.
There is also the Scheidmann source in Germany but I think the quality is similar to IE and they are shorties. Your reasoning is what is keeping me interested in the group buy also. Certainly not going to lose $ at this price :). I still would like a SFDon, Mario, etc. to weigh in on header effectiveness on a stock motor but I'll get off that kick.
 

Stan

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Jigs are for sale

from their website,

All models of jigs/sample headers/bending and assembly instructions are available for sale. *Contact Judy or Jere Stahl if interested.

I don't know the first thing about bending pipe.... Maybe Sven!
 

rsporsche

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this is from korman's website - there is no comment regarding cutting the frame rail. see other fitting notes. also see that they don't even sell the 1 5/8" header (only for race engines). for radical engines, they use the 1 1/2".

Korman-Stahl Headers
These high quality headers provide a 6-10% power increase on stock engines, much more on high performance engines. Engineered for trouble free fit and long service. Also available with ceramic thermal barrier coating (described below) for additional performance, durability and improved appearance.
BMW 2800, 3.0, 3.0CS, Bavaria
1 1/4" 18215114 (1)
1 3/8" 18215138 (1)
1 1/2" High Perf. 18215150 (2)

Notes:
(1) Connector length to the center resonator pipe must be shortened. If a 4 speed model has been converted to a 5 speed, must trim the edge of the transmission support bracket.
(2) Only for 3.0, 3.3, 3.5 engines over 270HP, must radius edge of engine casting for clearance.
 

Brian D

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I'm coming at this from a slightly different position, Paul Burke is finishing up my 3.5 engine with 10.5:1 compression and a N31 cam(can't remember the specs right now, sorry). I'll be calling him next week for his opinion on what size primaries to run, and I'll ask about engines that are closer to stock also.
 

Stan

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Paul Cain's

"Yes, lots of work went into swapping center mufflers. headers are Hargte 1 5/8 '' tubes with dual exhausts to the rear bumper. "
 

AceAndrew

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X 3.
There is also the Scheidmann source in Germany but I think the quality is similar to IE and they are shorties.

The quality of the Schmeidmann are not similar to the IE headers. The Schmeidmann's are made from a Chinese manufacturer and leave quite a bit to be desired. I could go on, but would rather not.

On the pipe sizing, the IE intermediate-length headers do follow a different design methodology than the Korman/stahl longtubes. To directly compare primary sizing between them (1 3/8 vs 1 5/8 ) would be akin to debating to different religions.
 

TodB

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The quality of the Schmeidmann are not similar to the IE headers. The Schmeidmann's are made from a Chinese manufacturer and leave quite a bit to be desired. I could go on, but would rather not.
I hadn't heard the best about the IE header quality either.
 
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AceAndrew

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I hadn't heard the best about the IE header quality either.

I'd be interested in your source.

In terms of quality they are made here locally by one of the old guard (has been racing and making headers since the the 60's). They are at least equal to the Stahls in manufacturing quality. I've got some of both here if you'd like close ups.

 

TodB

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I'd have to dig. There has been talk on the mye28 site about the build quality and fitment. Some have had good results, some have not. Perhaps the quality is not as bad as the Scheidmann product.
 
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