My cousin just told me that she had a turbo from an old audi she used to have, supposibly it was a spare that came off a parts car or something and was in good shape, I was wondering if this could work on a 12a running some sort of blowthrough setup. It was a stock turbo from a mid 80s 5 cylinder audi, and as long as it doesnt have any play in the turbines could this be a possible cantidate for a 12a blowthrough turbo setup? Can anyone tell me if this is something worth thinking about or should I just forget about this old audi turbo and find something more suitable?

 

It should work.

as long as you know what you are doing?

 

a turbo is a turbo find out what kinda psi those old audis made and power and if its good enough for you ive thought of snagging one off of an 90s 4 door see if shes got the IC

 

There are a lot of things that matter when selecting a turbo. You must select the correct trim and A/R for the exhaust (I have found that for a 12a, a .7-.96 A/R is ok, .86 being the best). Also, shaft play is the worst thing to judge a turbo. You need to know if the turbo was leaking/burning oil. Shaft play is normal, and is ok as long as the compressor wheel doesnt hit the compressor housing.

 

Shaft play up and down is normal, to a degree.The oil will take up the slack.Shaft play in and out is bad.

The Audi 5 bangers were in the range of 2.5L I think.Probably about 6-8psi,which is average for factory cars.
A stock 12A moves as much air as a 2.3L piston engine,approximately.The turbo should be OK for mild use.Any porting or upgrade to a 13B and you should look for a bigger unit.If you just want to make 5-6lbs on a stock port 12A,then it should be fine,provided the hot side is large enough to flow the air.Youd be surprised how much bigger stock rotary turbos(Hitachi T18) are compared to stock turbos on other cars.Some of the 4 bangers have turbo inlets the size of a quarter!

 

The 5 cylinder audis are around 2.1L to 2.2L. My guess is that the exhaust side is too small..

 

what year was it off of? I have the factory manuals if you need a reference

it will rather be a K24 or a K26 if memory serves me seanrot uses the k26 on his car.

I will dig out the books today to see what I can let you know

 

I have been called out

Im running a KKK K26 aftermarket turbo on my car it came as a kit from Japan. I'm sure the audi factory turbo is a K26. But you'll have more to deal with than me if you use a factory turbo. Most of them use water and oil to cool the turbo. Mine was just oil, less plumming on the install.

Your going to have to find a t3 flange for the exhaust manifold. You will probably have to get that custom made. That in itself is enough for me to just get a TII turbo and manifold and make it work.

If she is just going to give it to you. Put it on ebay and use the funds from it to get the TII turbo.

 

any audi 5000 turbo made in 1985 or later had the water cooling, if that helps anyone.
here is a map for whoever can read it.

 

So this would rule out the GT17 I have from a leftover TDI... unless I can find another and create a parallel turbo setup, running off each rotor.