If you want the most, look at Stahl. I have used them on everything from D gas to FP. For the Mini they are in the $$$$ range as apposed to $$$ for an FP Spitfire, but they work if you are looking for a little more. Ask any door car racer what the best off the shelf header you can buy. SS is real nice but the fact is you won't see one on many, if any race cars. SS over long periods of race time tend to stress crack ( for a header ). This is not so common on most of the headers "we" would use for the occassional auto-x or track day but for a pure race car, SS is rarely used.

If you ultimately decide that Stahl is your choice, you will want to know what diameter the primary wants to be for your application. There are too many little details to explain here that pertain to the primaries & your application.
Bottom line, talk to Don & he will give you the best info on the header style & primary you need.

 

Bottom line not counting bragging rights about having the so-called best.
If you look at the potential horsepower and torque per dollar numbers when comparing these exhaust systems this is a pitiful investment.

 

Bold and correct. I have tested four of the ones I mentioned both on the track and on the dyno.
All of the headers except the Stahl gave very similar results probably because they all share the same basic flange and primary dimensions.
Maybe you’re not familiar with Stahl or what they do. That’s ok; go to http://stahlheaders.com/ and check it out. The differences are numerous and include flange design & shape, primary diameter & length, formed verses merger collector, material, and manufacturing technique.

What sort of dyno inreases did you see(tq and hp),and at what points across the rev range?

I see what you mean regarding the Stahl, I suppose the others are so short that they peak at 10,500ish

So are the Stahl flanges machinesd so they have anti reversion or are they a perfect match to the head?

 

I appreciate your interest but I am not sure if you are trying to actually learn about the product and its benefit or if you have other motives. I have a policy of not posting dyno numbers because comparisons cannot easily be made. All dyno numbers do is seems to lead to the spread of disinformation. I write about this on my web site. You can post any finding you gather about my products on your own -- I cannot stop you.

From http://www.stahlheaders.com/faq.htm#round
How do I fit a round tube into a square hole?
To form the tube to fit in the flange, we lay the end of the pipe on a vise, hammer and rotate in 90° increments until it fits into the flange. We then tack weld the pipe to the flange. After all 4 pipes are tack welded to the flange, we put the header in a vise on #1 pipe with the gasket site of the flanges facing up. We use a large rosebud tip to heat the part of the tubing that is sticking through the flange, or any other part of the tubing we want to form, to a dull red color. We then use a long punch, about 10" long, and lightly hammer on the side of the punch to form the tube. Great care must be taken to not overheat the tubing. It may takes as many as 15 or 20 cycles of heating and forming to finish one cylinder.
When the pipe is formed on one side of the flange, we tack weld the pipe to the flange to hold it in place with either MIG or TIG. Then reposition the header to hold it by another cylinder pipe, for example #3 cylinder. When finished forming all the pipes, we braze the pipe to the flange on the outside.
Why do Stahl Headers cost more?
That's a fair question. We'd much rather explain the price than apologize for quality like other manufacturers are forced to do when their product is compared side by side with a Stahl Header. Stahl Headers cost more because they take much longer to build. Each header is is built one set at a time. The processes we use result in headers that frequently last up to 10 years on a oval track car, and 20 to 25 years on a drag race vehicle. We use a flange that is selected to match your port shape and location. Our expertise in selecting the right tube / collector size combination is un-paralleled in the industry.
We were the pioneers of many technical components that are used today by the racing world in general. Stahl Headers dedication to quality has resulted in a product that is the standard by which others are judged.

 

Has anyone on NAM bought a stahl header and willing to share yet?

 

I just began selling them. Three people have purchased the entire system, one just a header. Only one of the five are NAMers.

 

Also, will the catalytic converter pass the CA SMOG emission test? Better yet, is there a CARB exemption number for the header?

 

I'm always learning Don even and so should anyone envolved in cars or motorsports where there is a stopwatch involved

You can private message me the figures if you like and I promise won't pass them on to anyone else.

Our dyno should be installed at the end of the week so we'll start testing in ernest next month, I will be making a header and mucking about with primary lengths but we will always quantify these in the real world at the dragstrip.

I have witnessed serious hp gains just by switching collectors

I'm glad to see that Stahl sponsor the PHR challenge,we actually gained 70hp just by redesigning a cam for my mates 496 BBC, this was on pump gas.

If you want to send a header over so we can always show yours as being the top dog you're more than welcome.

Anyway someone has got to take Isellem record away from him so he can come out of retirement

 

I put a Stahl header on my hotted up BMW 2002 (along with dual twin side draft Mikunis) back in '76.

 

Paul--Why go to all the trouble and expense of making your own header: Stahl is in the NHRA Hall of Fame!

 

If there is sign me up for one

 

I have used many Stahl headers but I have no experience with the Mini application but I can speak to the quality. The expresion "it has to look right to be right" applies here IMHO. There is no way I'm going to say it's the best thing since sliced bread or even that the HP & TQ is worth the money, since the OE piece is not that terrible. That said, if you are looking for an edge, Stahl products have been very good to me for a long time on everything from D gas to FP. They are worth a strong look. I'm hoping that a near by NAMer will get 1 ( he's thinking about it ). If time permits I'll make a trip to NJ to see Don & the header.

 

So is my best mate Billy, though I think Shannon deserves to be in there as well for putting up with him.

 

+1 (if there is a CARB exemption number) for at a total of at least two.

 

Here is a very interesting web site that anyone interested in this thread will probably like exploring.

https://www.headersbyed.com/index.htm

The kits and stuff are interesting, but the really great part is the discussion of reasons WHY so many manufactured headers are disappointing.

Enjoy.

 

I think the biggest problem today is the gains are very very small as Don has bravely quoted on his site 7whp for a header and system.

Whereas in Stahl and Eds heyday and those big V8 were coming out with those loverly cast iron log manifold it would be easy to pick up 30-60hp which sounds a lot more like money well spent.

On a personal note my stock header cat and one ball exhaust has been able to run 114mph which equals 301 flywheel hp so to me it doesn't seem like a bottleneck, now as I put a better head on then cam and even more nitrous will it hurt it?? we will see.

 

The 7 WHP quote is for a typical street header/cat back such as Milltek. Please note, I am not referring to the Stahl system.

 

Hi, I have the Megan racing header with a cat back exhaust. I need to pass emissions at the beginning of the year. I like running without a cat. What do I need to make a removable cat so I can swap my test pipe and cat when emission time comes?

Thanks,
Hayden

 

The test pipe should be the same size as the CAT, so you'll just have to get yourself a CAT (oem would be best), and have an exhaust shop weld on matching flanges so you can bolt it in.

Basicly, buy yourself a CAT & find a custom or non chain exhaust shop & tell them what you need.

 

Awesome thank you. Quick question, why would you prefer OEM cat over something like the Megan high flow cat?

Thanks,
Hayden

 

Mostly code issues, if you're just trying to pass an inspection & going to remove it right after, less chance of a code for that period of time, if you're planning in running it, not only less of a chance of throwing a code, but the OEM's historicly last far longer due to the extra high exhaust heat our cars generate, and also, on our cars the performance gain, high flow-vs-oem are debatable and in some situations (specific engine mods) the OEM's actually work better because of the extra back pressure.

 

What, you didn't believe me Hayden? Sometimes I know what I'm talking about

 

Wow, Stahl is a couple miles from my house. Not that I need a header right now, but...
The MINI model is only $640 fully assembled (as of 5/2008 anyway).
A picture of one would be nice.

 

so, anyone else own those 200$ megan headers? any issues? i figure, if im going to get headers it would be those, obviously because of the price to HP / TQ gain ratio. why spend 2x as much if your not getting 2x the power eh?

i already have the JCW exhaust, so from the cat-back shouldnt be an issue as far as flow.