Turbo for AAZ

[Big Daddy Roth]

I'm going to be swapping the AAZ in my B3 with a factory rebuild (I got a smokin' deal on it). I'll upping the turbo from the Garret T2. To what, I'm not exactly sure yet.

I have a K26 from a Audi 5KT. Would the be a good swap? Or should I be looking for a K03?



I can easily make an adapter.

[burn_your_money]

What kind of boost do you hope to make?

What did the T2 lack that you hope the new turbo will provide?

[Big Daddy Roth]

approx 25psi.

Working with Giles pump, intercooler, and open exhaust.

The T2 is balls.

[stewardc]

The bigger turbo will give more boost, but more lag also. I tried a T3 from a 1.6 TD on my AAZ and like it well enough. It easily makes 25psi when you need it, but EGTs tend to be a bit high.

[burn_your_money]

Guiliano has a K26 stuffed in a K24 housing and his EGTs are through the roof. I don't think it's a good match based on his car's results. A T3 or K24 is probably the easiest choice. Giles has a T3 on his Passat and doesn't have a problem with EGTs. He is running 20 PSI.

[dcg9381]

Before deciding on a turbo, learn to read the turbo maps - find one in the pressure ratio (14psi = pressure ratio of 2) and CFM flow that is still efficient for your motor.. You can basically equate CFM to HP, some estimation is required... but the better that turbo is in terms of efficiency, the cooler your EGTs will run and you'll make more power.

A more efficient turbo can produce the same power at 5 psi less than a non-efficient one.

You can also alter AR ratios on the Garrett series to tweak the spool up and high end flow...

[1outof5]

Before deciding on a turbo, learn to read the turbo maps -...

where can I find those kind of explanations? might be worth adding to the FAQ section ...

[Rabbit on Roids]

Guiliano has a K26 stuffed in a K24 housing and his EGTs are through the roof. I don't think it's a good match based on his car's results. A T3 or K24 is probably the easiest choice. Giles has a T3 on his Passat and doesn't have a problem with EGTs. He is running 20 PSI.

its pretty much agreed upon that a K24 hybrid runs hotter than a straight K24 or straight K26.

[Rabbit on Roids]

I'm going to be swapping the AAZ in my B3 with a factory rebuild (I got a smokin' deal on it). I'll upping the turbo from the Garret T2. To what, I'm not exactly sure yet.

I have a K26 from a Audi 5KT. Would the be a good swap? Or should I be looking for a K03?
I can easily make an adapter.

a K03 is basically the smallest turbo a vw came with, while a K26 is the biggest turbo they came with, that i know of atleast. a K26 is gonna be one hellaciously laggy turbo. they are even bigger than a stock T3 or K24. by quite a bit.

i just think its funny that the 2 turbos you have are good for 2 completely different uses. one has hardly any spool time, but hardly any max boost either. the other has a huge spool time, and makes lots of max boost. basically you have a great daily driver turbo (K03), and a good drag racing turbo(K26).

[burn_your_money]

Guiliano has a K26 stuffed in a K24 housing and his EGTs are through the roof. I don't think it's a good match based on his car's results. A T3 or K24 is probably the easiest choice. Giles has a T3 on his Passat and doesn't have a problem with EGTs. He is running 20 PSI.

its pretty much agreed upon that a K24 hybrid runs hotter than a straight K24 or straight K26.

Most hybrids have the K26 compressor and K24 turbine (or the other way around, I forget) Guiliano has the whole K26 stuffed into the K24 housings so that it would bolt on.

[wildenbeast]

I'm going to be swapping the AAZ in my B3 with a factory rebuild (I got a smokin' deal on it). I'll upping the turbo from the Garret T2.

What condition is your T2?  How many miles?  I would be very interested in purchasing it from you.

[Runt]

Most hybrids have the K26 compressor and K24 turbine (or the other way around, I forget) Guiliano has the whole K26 stuffed into the K24 housings so that it would bolt on.

I can see how this would create a world of problems.  Turbos compress the air by moving it, not by squeezing it.  (a sloppy explanation, but it makes the point.)  Stuffing the bigger wheels into the smaller housing will probably help spool, but I'd actually expect compressor temperature to be higher than either original wheel/housing pair, because the wheel is moving more air, but without the room for the air to move away from the wheel.  I'd also be on the lookout for some of the nasty compressor surge effects, which can damage te turbo wheels.  On the turbine side, the problem is even worse.  A bigger wheel in a smaller housing will definitely start to spin faster, but even a cursory analysis would expect more restriction with this setup. 
'Turbo Maps' are great, but they can be difficult to read, some companies publish their maps differently, eg. holset, and nobody reliably publishes any information on the turbine sides, which have more to do with spooling than the compressor sides.  Logically, if spooling is the point that the turbo starts to create boost, the drive side that starts it spinning is the larger initial contributor.  The compressor map is useful in determining that the compressor will happily and mostly efficiently compress the required amount of air, without heating it up to much, or entering a surge condition.
I have a couple ideas that I've picked up from gasser hotrodding that I'm curious to try, but I have not had the chance to actually try any of them yet.  I'll start a new thread, if anyone's interested in an unorthodox idea or two check it out.

[stewardc]

We need a turbo service like Giles offers for pumps. Call a number, tell him your combo and driving style....POOF...the perfect turbo for your app.

[GEE-BEE]

I would say GPOPSHOP.com is the best for the price....

Basic OHC 395.00

They also do Ceramic coated housing for cooler temp's and corrosion control.