Audi Sport wastegates

[Hollizini]

Hello!
I think I've read everything there is about Audis wastegates in the rallying and racing cars, and there isnt much to find.
James Bufkin says that the bigger wg in the umluft setup in S1 was a Porsche 930 wg and from what I can tell only a handful of cars seems to share the membrane housing, thats all.
Exhaust housing looks like a one of part for the S1 with wider mounting flanges and bigger housing, seems costly to have a special part taken into production for ~30 wastegates...
The smaller he says would be from a 944 (951) which does not share any resemblance.

Have anyone of you any knowledge?

Cheers,

[Error404]

I wonder if it is a modified 935 part? I saw pictures of a 935 part which looked similar and carried a 930 part number. Surplus from Porsche’s old big-budget parts bin perhaps?

[Hollizini]

Usually the exhaust housings have a 935 part number and the membrane housing a 930 number, but as far as My googleing goes it seems not to be a Porsche specific part either, neither of Porsches racing cars uses a similar wastegate. The Audi Sport exhaust housing as well as the lower membrane housing seems totally uniqe from what I have found out so far.

[PRY4SNO]

What does this 930 part do that modern wastegates cannot?

Or is your interest more in line with understanding the history?

[blackS2]

Just some photos from my camera...

[Hollizini]

What does this 930 part do that modern wastegates cannot?

Or is your interest more in line with understanding the history?

The last, kind of!

I run a 2,2T with a 90 quattro Imsa 34.76 turbo bolted on a S1E2 copy exhaust manifold, I'am not intresting in building in a modern wastegate in an Audi Sport tribute.
Wanna see how difficult it is to find out what parts it is made out of or what path I will take in the wastegate decision.

[Error404]

It seems there were a few flavours used. Those that blackS2 posted looks very similar to the 935 part, with the Porsche logo and p/n machined off.

1383358239_ven12_531.jpg

[PRY4SNO]

The last, kind of!

I run a 2,2T with a 90 quattro Imsa 34.76 turbo bolted on a S1E2 copy exhaust manifold, I'am not intresting in building in a modern wastegate in an Audi Sport tribute.
Wanna see how difficult it is to find out what parts it is made out of or what path I will take in the wastegate decision.

That's fantastic. Appreciate your attention to detail and effort to preserve history.

I'd love to see more of your project, do you have a build thread?

[twoqu]

I looked into this previously and could not find the distinctive flange on any Porsche wastegates including the exotic ones! Conclusion is Audi had their own one cast and used the Porsche larger valves and hardware. Although on occasion they used the familiar Audi chamber!
So probably the next best thing is going to be the stock Porsche one .
There may be some interchange between the two, Audi and Porsche, to get the appearance. Unfortunately the Porsche ones were not cheap enough at the time, or indeed now to investigate for purely cosmetic purposes.

[Hollizini]

That's fantastic. Appreciate your attention to detail and effort to preserve history.

I'd love to see more of your project, do you have a build thread?

No project thread to this date, but maybe I should start one in the near future, here is a early mockup on the hotside story and a bonus pic on the Imsa drysump copy i accuired.

Maybe the best path for me will be a Porsche wastegate and dont bother that much in all the appearence, would look authentic enough.

[twoqu]

Hopefully attached are some pics of the Audi Motorsport wastegate from various vehicles. You may be able to identify something of use.
It's possible the difference in the wastegate flange is due to Audi using a seat (ring) for the valve as per usual rather than the Porsche plate. It looks to be one piece.

[Hollizini]

Hopefully attached are some pics of the Audi Motorsport wastegate from various vehicles. You may be able to identify something of use.
It's possible the difference in the wastegate flange is due to Audi using a seat (ring) for the valve as per usual rather than the Porsche plate. It looks to be one piece.

Great pics!
I think I will have to search the internet a bit further to find out if there is some info on this out there.
I have tried to come in contact with James Bufkin but sadly he did not answer to my questions.

Thanks guys!