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Maxing Small 21u Rb25det R33 Turbine Housing With High Flow. What Power Would You Expect?


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I did read many posts in regarding to high flowing with the factory 21U RB25det R33 turbine housings. I did some testing in it with a modified exhaust wheel, I like to share this information publicly and I believe this is the absolute max this thing can flow.

I also managed to hold 20psi flat with that small housing using a wastegate controller and a high pressure actuator on 98 fuel.

The max power it managed was a stunning 297rwkws when its cold, with final run of 273rwkws consistent. The little sucker was burning red hot.

357658.jpg

357658boost.jpg

Video footage for all 3x runs are recorded:

video.JPG

I'm little bit concert with high back pressure. So this profile will not yet be commercially available after further testing and examination for component wear.

very nice, may i ask what supporting mods are used to achieve the above power figures, besides the already stated? also what would be a ball park figure on getting one of these done if it were to go commericially available? cheers and good job.

It runs off a factory standard rebuild engine with stock engine head with fuel mods. There is nothing in there that could alter the behavior of the turbo on a stock setup.

The heat would be a major problem. We did a check up run after the turbo cooled down, made 293rwkws. lol Any thing above 270rwkws for this housing isn't consistent. I will remove this turbo off the test car in few weeks time and see what the bearings and collars be like, If nothing is excessive then this will be replacing the current 240rwkws profile.

Its the same car he run 300+kw in last week with a different turbo..

Man that car has a different turbo in it every week... :happy:

Power curve actually looks pretty sweet too..

I have achieved similar results on more than 1 rb25 using a highflowed rb25 turbo with the OP6 housing and tolulene mixed fuel running a very agressive tune (all supporting mods including cams and a VERY freeflowing exhaust).

I have never posted dyno charts (and don't intend to) because some keyboard warrior is just going to call me a liar.

what about exhaust manifold gas temps? i wouldnt be worried about the turbo... its the valves i would be worried for!

plus the extreame temps isnt going to help with knock and summer is around the corner... i would be toning this down a bit for safety

I have achieved similar results on more than 1 rb25 using a highflowed rb25 turbo with the OP6 housing and tolulene mixed fuel running a very agressive tune (all supporting mods including cams and a VERY freeflowing exhaust).

I have never posted dyno charts (and don't intend to) because some keyboard warrior is just going to call me a liar.

we are talking pump 98 here no jungle juice.

impressive, but, to me it looks laggy for a std 33 housing! never thought id say that about a factory housing lol.

a bar at ~3700 and full boost at ~4000.

looks very similar to a OP6 / 3076 curve. a good cheaper? alternative.

nevertheless a good achievement for a 33 housing. good street only turbo.

dont worry about the heat, its not like you would have it that hot on the street...

impressive, but, to me it looks laggy for a std 33 housing! never thought id say that about a factory housing lol.

a bar at ~3700 and full boost at ~4000.

looks very similar to a OP6 / 3076 curve. a good cheaper? alternative.

nevertheless a good achievement for a 33 housing. good street only turbo.

dont worry about the heat, its not like you would have it that hot on the street...

I agree, its not like you are pumping that power out continuously on the street but an egt gauge would be a good idea. With a smaller exducer you wouldnt loose all that much top end, as the nozzle is the restriction, but it will come on much earlier.

I have 20 psi by 3k, dropping to 17 at redline, I plan to try the added spring first but what actuator was this running?

post-63525-1285677569_thumb.jpg

Its running a high pressure actuator with a gate controller. Its not possible to hold boost on the actuator alone. and that is a 23psi atmospheric scaled actuator.

The power curve looks pretty average compare to the ATR43G3s, but on road this is very responsive, comes in boost nice and early on 1st, 2nd, 3rd, totally different driving ability compare to .82 rears.

Everytime i read your threads and all the power and response your getting from hi-flows etc it just confuses me more which one to go for! haha

impressive, but, to me it looks laggy for a std 33 housing! never thought id say that about a factory housing lol.

a bar at ~3700 and full boost at ~4000.

looks very similar to a OP6 / 3076 curve. a good cheaper? alternative.

nevertheless a good achievement for a 33 housing. good street only turbo.

dont worry about the heat, its not like you would have it that hot on the street...

Ask Tao to post up a ramp rate comparison, ive had a few cars come in lately that are being tuned on unrealistic ramp rates, this ramp rate moves the curve around alot. the above graph will make 18o-200rwkw @ 4000 by runnning a pretty popular Dyno Dynamics ramp rate.... makes for a nice graph but unrealistic.

Its the same car he run 300+kw in last week with a different turbo..

Man that car has a different turbo in it every week... :)

You do realise he owns/works for a turbo company Hypergear and that car is a demo vehicle...

I wonder just how hot it would run when pushed hard.

I see people saying it would be OK for good power on the street, but personally that would mean dead engine in my hands.

I wonder just how hot it would run when pushed hard.

I see people saying it would be OK for good power on the street, but personally that would mean dead engine in my hands.

@ 270 we could do run after run without issue @ 290+ it was starting to heat up and required constant timing chances to keep it happy. do 2 or 3 runs and the timing would fall back to where it was @ 270... then it would do run after run @ that timing all day long with around 3 degrees headroom

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