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hey guys !!!!

got a hi-flowed turbo and all supporting mods on my r33 s-II (coil packs, fmic,z32 afm, pod etc.).

the turbo can't flow enough air at high rpm so it drops from 18psi to 15psi and making only 301rwhp.

any ideas/ suggestions on what my options are to get to 350hp mark ?????

Will I have to get a new turbo altogether or are there any other options???

If new bigger turbo is the only answer, what turbo? are there any bolt on solutions?

here's the dyno graph ..

post-58092-1229821581_thumb.jpg

Cheers !!

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How big is the front, if the front is big enough maybe its just the rear housing that is not flowing enough, in that case the simple option is a vg30 rear housing which is .8 not .6 like and rb25 turbo, i have a high flow with one, only have fmic, k&n panel filter, 3" exhaust, hi flow cat and one piece split dump and it makes 299 rwhp, once i put in bigger injectors, z32, fule pump and management i will be maxing it out at around 350 rwhp.

My dyno graph is much the same as yours but i am making the same power as you at the same rpm but with less boost, my 299hp was at 6000rpm @ 14psi.

post-27276-1229835901_thumb.jpg

what wastegate actuator are you using? if you have a rb25 one then they are weak as piss and can cause this.

get a upgraded wastegate actuator with a 15psi spring and then re-tune it to 20psi and you should get close to the power your after

  W0rp3D said:
How big is the front, if the front is big enough maybe its just the rear housing that is not flowing enough, in that case the simple option is a vg30 rear housing which is .8 not .6 like and rb25 turbo, i have a high flow with one, only have fmic, k&n panel filter, 3" exhaust, hi flow cat and one piece split dump and it makes 299 rwhp, once i put in bigger injectors, z32, fule pump and management i will be maxing it out at around 350 rwhp.

My dyno graph is much the same as yours but i am making the same power as you at the same rpm but with less boost, my 299hp was at 6000rpm @ 14psi.

post-27276-1229835901_thumb.jpg

  Guilt-Toy said:
what wastegate actuator are you using? if you have a rb25 one then they are weak as piss and can cause this.

get a upgraded wastegate actuator with a 15psi spring and then re-tune it to 20psi and you should get close to the power your after

Thanks for the replies guys, I'll check with the guy who hi-flod the turbo, what housing .6 or .8 and what wastegate actuator were used. At this stageall I know is the wastegate is internal...

checked with the workshop and it was the stock rb25 wastegate actuator used (3 psi or something). will change this to a better one in Jan... he said this will be a 13.8psi... will this do the trick??? I guess only one way to find out !!!

  • 3 weeks later...
  Ninja_09 said:
checked with the workshop and it was the stock rb25 wastegate actuator used (3 psi or something). will change this to a better one in Jan... he said this will be a 13.8psi... will this do the trick??? I guess only one way to find out !!!

Just wondering if setting the higher boost duty circle will help holding the boost?? :D

  Ninja_09 said:
checked with the workshop and it was the stock rb25 wastegate actuator used (3 psi or something). will change this to a better one in Jan... he said this will be a 13.8psi... will this do the trick??? I guess only one way to find out !!!

Can anyone confirm the size of the stock wastegate actuator? I thought it was 7psi?? Cause i think they did the same with my gt3076r upgrade. Its a lag fest. I got a 18psi spring going on next tuesday.

In your case there is no way you will make 350rwhp with a high flow. I bet Andrew told you that you wouldnt see those figures too. Thats why i went the gt3076r and not a highflow.

However i reckon you might get 325rwhp at most on his dyno with a 1 bar actuator. The boost will come on heaps early and should hold all the way.

  Pattygtst said:
Can anyone confirm the size of the stock wastegate actuator? I thought it was 7psi??

I was under the impression it was 5psi.

5psi to get the low boost setting and 7psi for the highboost setting (in the stock boost controller).

um, rb25 actuators are 7psi, rb20 actuators are 10psi, HKS actuators are adjustable but from memory the minimum is 14psi? correct me if im wrong,

thats why people say using the rb20 actuator on the 25 turbo ends up working better,

HKS actuators cost mmm well with our crap exchange rate now probably $200, was $130 delivered when i checked last before the crap dollar

  Pattygtst said:
Can anyone confirm the size of the stock wastegate actuator? I thought it was 7psi?? Cause i think they did the same with my gt3076r upgrade. Its a lag fest. I got a 18psi spring going on next tuesday.

In your case there is no way you will make 350rwhp with a high flow. I bet Andrew told you that you wouldnt see those figures too. Thats why i went the gt3076r and not a highflow.

However i reckon you might get 325rwhp at most on his dyno with a 1 bar actuator. The boost will come on heaps early and should hold all the way.

I kinda realised that I'm not gonna get 350hp with this turbo, but if I can run 17-18psi and hold through out the rev range I'll be more than happy (with what ever the rwhp number I get)

I don't wanna pay for whole new turbo setup just for few hp

Is it straight forward to change the actuator to a 1 bar actuator? which brand is recomended??? are there 18 psi actuators out there?

and yeah !!! Andrew told me that 350 is not gonna happen with this turbo. :D

Just get the HKS actuator. My stock actuator got busted, stuck at 0.4bar all the time. Got the adjustable and wind it up til 0.73bar which was max for the stock turbo (using stock ecu). Winding it up anymore would cause like hitting a wall kinda feeling. lol

BTW the HKS acutator can go over 1 bar easily.

post-48477-1232715076_thumb.jpg

Edited by teng
  Ninja_09 said:
I kinda realised that I'm not gonna get 350hp with this turbo, but if I can run 17-18psi and hold through out the rev range I'll be more than happy (with what ever the rwhp number I get)

I don't wanna pay for whole new turbo setup just for few hp

Is it straight forward to change the actuator to a 1 bar actuator? which brand is recomended??? are there 18 psi actuators out there?

and yeah !!! Andrew told me that 350 is not gonna happen with this turbo. :P

Well if you hadnt noticed your thread says im after 350rwhp. Your asking the wrong questions.

Get a suitable turbo first!

Do people know how much you can get out of a high flowed r33 turbo? Mines a RB25 and im making 290Hp at 12psi. But they guy that tunes it said he wound the boost up too 20psi but only got about 10 more Hp. Does this sound right?

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