S1 Evo II exhaust manifold for sale

[aelred]

S1 E2 Exhaust Manifold now sold!!!!

[james_bufkin]

The grill is 1st on the list.
Other are making the rest of the bits.

[AndyP]

Excuse my ignorance, but WTF is a piggy umluft flange?

Sounds like something from a Monty Python sketch

[james_bufkin]

Good question.

Those S1 manifolds had an anti-lag setup on it which Audi called umluft.
The system was withdrawn in its heyday and engines had the system removed. The manifolds were modified by cutting off the umluft and plugging the holes.

Most S1 manifolds will have the umluft cut off and the pieces are gone. Two, Hohenester's glass display case and PP car in Ingolstadt seem to have the umluft still
on. I have reassembled and welded mine back together. Others are plugged off.

Here is a mockup using some parts. You can see the guts of the system.


S1 manifold with Umluft


S1 manifold without. See the nicely welded plugs where the holes are supposed to be. The very thick flange on the head.

[AndyP]

Very interesting, thanks

Is it true that in an attempt to minimise lag in the Pike Peak car they tried running with a cylinder of compressed air that was plumbed into the turbo. When the throttle was shut the compressed air kept the turbo spinning at full speed. I can't remember where I read it, but an interesting concept if it was true.

[james_bufkin]

Don't think so,
They used the system you see above. When off throttle the 2nd wastegate would open by being triggered off the Vacuum pressure on the backside of the throttle body. Thus, oxygen rich charge air could enter the exhaust manifold and intermingle with the fuel rich exhaust which would be suddenly rich due to the throttle close. This would burn in the exhaust manifold. Which would run the turbo more which would run more air through the exhaust, etc etc. Pretty much a system that feeds on itself until it reaches some happy rate of Rage which is probably at the upper operating limit of the turbocharger. The minute you crack the Throttle back open the 2nd wastegate would shut and all that charge air which was whizzing through the exhaust system would now be blasting through the engine. So it pretty much ran the manifold like a turbojet. I'm sure the crazyfast computers of the day, couldn't keep up with the system and it ran itself into puddles of molten metal. Bruno used it and said it produced 1.5 bar of boost at idle and had instant power with no lag. It was very hard on the exhaust valves as it produced very high exhaust pressures and temperatures.

A system very similar to this can be seen on modern WRC cars. They use a mechanical type of Anti-lag as well as a mis-fire type of anti-lag which is so very common to Standalone ECUs.

[Jon441cc]

A little off the subject, But was this wastegate used on the umluft set-up ?

Part # 930 123 214 1R



Cheers Jon

[james_bufkin]

Close, but the two I have are slightly different. The bottom portion of that wastegate will bolt to the secondary or the umluft portion of the manifold. Audi had removed material on the flange for weight and shaved some of the base off. To which isbolted another flange with a straight tube going down. From the body to the cap, the wastegate I have has only 3 bolts. And the cap itself is definatley a porsche cap because the one on the car had the words "Porsche" ground off with only the date 7/3/85 scratched in there. The other cap still has the word Porsche on top. It was a spare and is brand new.

But a picture might help.

[Jon441cc]

Does anyone know what material the manifold was made from ?

Cheers Jon

[s2dude]

Inconnel I "think"
The most awesome metal out there

[james_bufkin]

yes Inconel

[Chris5044]

does this antilag wear your car out .. or could you happily have it fitted? .... I 've heard of mitsobushi's having antilag .... i'd guess tho that they were also their daily driver and has anyone here had antilag fitted to their car?

[Jamo]

injecting fuel into hot exhaust gasses raising the the temo to 1000c and over does wonders for reliability!

[james_bufkin]

The Audi system injected fuel and O2 into the exhaust stream.
lots of popping and flames. At least you won't foul your plugs.

Yeah, its a no bueno kind of thing. Basically do it if you have really deep pockets and don't mind rebuilding the head frequently.

[saltinot]

Most S1 manifolds will have the umluft cut off and the pieces are gone. Two, Hohenester's glass display case and PP car in Ingolstadt seem to have the umluft still
on. I have reassembled and welded mine back together. Others are plugged off.

I snapped a few shots of the "umluft" exhaust manifold while I was at Hohenester in 2005. A very interesting piece of engineering. It appeared to be new and only 6000DM. Anyone got a few old Marks they want to give me?