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What's the HP limit for the 21U turbine housing?

As per title what is the the HP limit for the 21U housing due to backpressure?

(I'm talking about high flowed units)

 

Thank you!

Just found this, so 270RKW at best?

 

 

Edited by Torques

I pulled 293rwkws on a 21U once with a custom CHRA set and tones of work to the turbine housing. The problem is OEM housing does not contain enough materials to containing a big enough turbine wheel. For that experiment I deliberately broke through the rear housing then filled it back with blanks. I got pretty good result, but not for the time and efforts put in.   

3576297.jpg

Thanks for the replies ... I'm about to install a new hybrid with billet wheel.

My car has already a hybrid (21U) installed and makes about 14PSI @ 3500rpm  / 540NM @ 3900 and about 260KW at the rear.

I like the responsiveness but the engine gradually runs out of urgency from 5000rpm onwards (boost declines), so 280KW+ would be nice.

Now I could have the OP6 housing machined and put on that new turbo but I don't want to introduce too much lag.

(car is used mainly in traffic or around town)

 

I read here that I would lose about 500rpm for same boost levels ? (OP6 vs 21U)

 

 

 

 

 

TT2.jpg

TT1.jpg

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BOOST.jpg

Both R33 RB25det not Neo. using identical size core, the 21U is more responsive while OP6 made more power.  also correction on the dyno reading of the modified 21U rear housing on Friday's the 10th post, the correct reading has been updated (on P98 fuel) 

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