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Looking for a small turbo with a high pressure ratio

I've been racing a turbocharged Honda CX500 at Bonneville the last couple years and I'm hitting the limits of my current setup. Its a 500cc engine running a K03-2075 (not ideal but works) on methanol and sometimes race gas. The bike has set a couple records but there is more in it with the right setup. I'm looking for a turbo that can put out a 4.0 pressure ratio at about 21lbs/m. right now the setup with the k03 is at 2.6PR at approx 15lbs/m, and intake air temps are horrendous. We are sitting at 140rwhp and want to get to 200.
It seems like every small turbo I have found just cant supply the pressure, does it exist? or is going compound the only way?
Thanks!
-Luke
Anderson Miller Racing

Sounds to me like you need a custom hybrid turbo of some sort. You need the small turbine as you’re only working with 500cc displacement, but you need a bigger compressor so it can push more air, as for your AIT, are you running an intercooler? Maybe you need a bigger one or a switch to water/air charge cooler to increase efficiency. Are you running the fuel injection throttle bodies setup from a GL650 or are you running carbs? Draw thru or blow thru?

Quote:

Originally Posted by Daveyg (Post 1313006)

No intercooler, but this is methanol fueled so IAT isnt an issue, the intake even gets a little frosty after a long pull. This bike is running megasquirt fuel injection so no carbs to worry about. I agree that the turbine and the displacement of the engine are somewhat mismatched. The compressor side seems to be the real issue though. The turbo I have now is really running along the surge line on the map in real world operation, meaning the engine doesn't physically flow enough air at a given pressure to be ideal for the compressor. If I raise the pressure any higher the turbo will overspeed (according to the compressor map, I have no way of measuring turbo speed), so Im looking for a compressor that can really lay down the pressure at small flow volumes