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I'm maxed out on my 745/kkk27 turbo, but don't want to replumb, new ex.manifold, etc. Is anyone using the upgrade turbo w/ the gt wheel?
Todd, do you still offer it?
How much improvement over stock turbo?
tia

It's still available. I have always used the 60mm Garrett wheel. It has the ability to support more HP and spools slightly quicker.

Hi Todd,
Have you got any dyno data? How much better is it, than stock turbo? I'm using a mbc. Cranked down on the mbc,(wastegate spring only) I can get 18-19#.

I have been using one for years on my 10/84 car and recently my drop in Tial I made work. Top end power is pretty different, it actually holds boost now, would love to see a before and after at 6psi just to see how much more power there is at 5500rpm. My car is out of fuel at 8-9psi with just the turbo upgrade, stock turbo is fine at 10psi. Still same goofy powerband nose dive around 4800 though, but that is all due to the Motronic 013. Stock M106s on MS2 actually pull a bit past 5k and just flatten out. I too was surprised by that dyno, some guy in WA had this on bimmerforums.

One of the other 745 guys dynoed ~270rwhp @7psi with his moded K27 (stock 013 Motronic), stock K27 on an M106 takes 14-15psi area to generate that with skyhigh IATs I would imagine due to that huge 47mm compressor wheel they had stock.

FWIW, I cannot imagine a stock K27 @ 19psi making more power than it would at 14psi.

marc79euro645 wrote:Hi Todd,
Have you got any dyno data? How much better is it, than stock turbo? I'm using a mbc. Cranked down on the mbc,(wastegate spring only) I can get 18-19#.

I only have stock data. My stock turbo m106 with a 1 bar spring would not hold 1 bar. It would peak at 15psi and fall to 12psi at redline. Made 273rwhp IIRC. Only mod was a 3" exhaust after the downpipe.