k26 max boost?

[rallydiesel]

To the turbo experts out there, what's the max boost a k26 can handle? I've got one of the larger ones from an Audi 5000. No wastegate on the turbine housing so I'm concerned it may be overboosted. This will eventually be on a high-output IDI. Still debating whether I should go 1.6 or 1.9 but in either case the head will be a heavily ported AAZ.

I may be using this as the high-flow turbo in a compound set-up. Here is the turbo map if anyone can give me some insight:

[Rabbit on Roids]

ive been told that they will make 35 psi. but not to go much over that.

[gldgti]

vertical axis on LHS shoes pressure ratio.... so for instance the numbers up the top show 2.8 - thats 2.8 times atmospheric pressure, which is 14.7psi - so thats 40-ish psi.

however, you need to look at how efficient the turbo is there, and for what flow rate. pick an rpm (say 4000) and work out a flow rate from that (using whatever boost you envisage) and that will let you plot a point on the map which will tell you the efficency of the compressor under those conditions.

on the map - the horizontal axis is gas flow rate, the vertical axis is pressure ratio. the longitudinal bands are compressor rpm, and the things that look like "isobars" on a weather map show compressor efficienct, n. for example, the highest efficiency is about 74% (n=0.74) for the innermost isobar.

[OM617]

The K26 is known as a heat pump above 15psi.

[rallydiesel]

Hmmm, I guess I will rebuild it and sell it to a gasser guy then.