Headers

kasbatts

kasbatts

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Any body got info on headers?, I'm going to make a set for myself RHD) but would like to know primary pipe lenght and diameter and secondary pipe lenghts and diameters, I read on a 5 series board somewhere 1 1/2 inch primarys and 2 inch secondarys, any body got a set lying around they could measure? pretty please :) :) :)
 
Header pipes

I have had 4 different sets of headers over the years: 2 Stahl, Headercraft and Supersprint. For 3.0 L engines, Stahl and Headercraft used 1 3/8" primaries, while Stahl made 1 1/2" primary headers for 3.5 engines. The collectors were basically the diameter of the exhaust system (entry pipes into front muffler).

I measured the Supersprint: 1 9/16" primaries and 1 3/4" secondaries; and Stahl 1 1/2": 1 1/2" primaries and 1 5/8" secondaries.

These were all made in the 80's, so I'm not sure what you can get now.
 
From Ireland Engineering: Go to the e3/e9 listing and look for Intake/Exhaust

NEW PRODUCT -- This header can fit the E9, E12, E24, E28, E34 with the M30 (big 6) engine. This header has 1 5/8" primary tubes so will work well for modified engines. If you would like the header ceramic coated add $140. The picture is of our proto type. We expect to have finished headers by 5/1/07. Cost has increased so the price is a little higher.

https://secure3.nexternal.com/share...usType=BtoC&Count1=363201320&Count2=280341744
 
Let me know how you get on as I may also want some if they can be made to fit on RHD.
cheers,Bryce
 
Let me know how you get on as I may also want some if they can be made to fit on RHD.
cheers,Bryce
Click to expand...

When I was talking last year to the fellow fabricating the IE headers, I asked whether they'd be available for RHD, and he said they would not. Apparently the collection point is right where it shouldn't be to clear RHD apparatus.

As I understand it, this particular header design is based on a Hartge unit for later applications (E28) with some modifications. Note that some creative downpipe fabrication will be be required to get from the end of the IE header to the resonator..

For RHD, Jaymic would know more.
 
The problem with RHD cars is that the exhaust has to clear the steering box, sneek around the clutch master cylinder and brake master cylinder.
A problem that wasn't really solved until BMW dumped the box and went for a rack a la E34 (5-series) of the 1990's

Besides the obvious of looking pretty a decent exhaust manifold will only give you another 2, maybe 3 BHP if your lucky.
There are some basic rules to follow if you decide to make your ownin the case of the 6 cylinder engine 3 into 2 into 1 is probably the best way to go

All individual exhaust pipes should be the same length and diameter, so in the case of the above the 3 pipes from cylinders 1,2 and 3 and 4,5 and 6 should be the same length as they enter the join. Then the 2 pipes sould be the same length as each other before joining into 1. There are other "tricks" which may give you another 1 or 2 BHP... But they are pretty minor and should only be considered if your going for all out racing!

To be honest BMW's RHD solution is pretty reasonable and you will gain more HP for your pound/dollar/yen/beans by careful porting, triple cutting of the valve seats etc than you will from a fancy looking exhaust manifold!

Ok I'll shut up now :roll:
Malc
 
Hi, comments re difficulty in achieving headers for RHD are what I thought and read in other posts. But if RHD headers can be made somehow, then my motivation would be purely visual and hopefully sound enhancement (not necessarly louder). But first I've got to get the car back together to make any noise at all!
Cheers,
Bryce
 
As a matter of interest, did the e24 have a steering box same as e9? and if they did are headers available for them? anyway us Kiwis love a challange, never say never and all that! allthough after i've started it may be a different tune I'm singing!!, still have'nt had any info on pipe LENGHTS yet can any one help here?
 
I'm sorry I can't be of any help with regards to lenght and diameter of primarys, the only thing I have to offer on this subject is that in order to be able to clear the gap between the engine block and the steering box maybe you should consider taking the primarys forwards before collecting them together. This was a solution used by TVR on some of their V8s when space was tight.
 
OK As far as I remember there as some critic points to remember:

1.. For a 6 cylinder engine either 6 into 1 or 6 into 2 into 1 is the best way to go.
2... Lets go 6 into 2 into 1 as it is probably the easiest to fabricate in this situation.
3... Each of the 6 pipes must have an area the same, or slightly larger than the area of the cylinder head exhaust ports.
4... The VOLUME of the 6 pipes must be equal to or greater than the VOLUME of each cylinder so for a 3litre engine the pipes must be at least 200 cc.
5... From the calculated volume and the known area you can work out the length of each of the 6 pipes. Now if you want longer pipes try and work in multiples of the volume, for example 400 cc, 600cc etc etc.
6...When joining the 2 sets of 3 pipes into the next pipe. this pipe should have an area equal to the sum of the 3 pipes and a length, in this case equal to a minimum of 600 cc in both cases them must be equal!
7... and finally when you join the 2 into 1 try and make the 1 have an area equal to the 2!

Make sense as I haven't explained it well :roll:

Pipes should be mandrel bent or use packed sand to ensure bends are smooth and kink free.

One last thing I have seen people use alkathene (spelling) pipe, the blue and yellow stuff used for water and gas mains to make a full scale model of a manifold before fabricating in steel. the stuff is easier to bend when dunked in hot water and or a heat gun is used.

Malc
 
Cool thanks Malc, all makes sense, I'll pass all that over my engine guy to see what his thoughts are, he's like a demi god down here very well respected by all in the motor sport fraternity, by the by, he also looks after a turbo 02 race car down here, a money no object car, best of everything that makes about 400 hp!, not all together slow in a straight line!
 
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