HRC Super 20g Upgrade "problems"

[Phatty95GSX]

Ok, im having some weird ass problems here.... just replaced my stock turbo on my 95 GSX... put the HRC super 20g turbo with 2g install kit on my gsx.... Have most basic mods but for some reason i can only boost 5psi max at around 6000 - 7000 rpm's. Have stock fuel injectors and fuel pump, but should be able to push the 10psi the wastegate can hold. Have a big exhaust leak at the o2 housing / downpipe, could that be the problem? Havent found any leaks in my Intercooler piping. Just sucks that when upgrading from stock to 20g you lose alot of hp... if anyone has a clue of what could be wrong a little help would be great. Just got the Turbo XS duel stage boost controller.. could it be the way my boost controller / wastegate / vacuum lines are hooked up? .... Have vacuum line running from intake manifold - bov.......... wastegate - boost controller ...... and turbo - boost controller.... nothin has to be run to intake correct, have stock intake with after marker filter. Let me know Thanks all....

 

[GSX4LIFE]

The leak at the downpipe will not affect boost. Just make sure thats where it's coming from. A leak at the manifold to turbo will cause boost problems. Try taking your boost controller out of the loop. Just run a hose from the nipple on the turbo to the wastegate actuator. If you get 8psi or so, the problem is in your hookup of the boost controller.

 

[badgsx]

Why would you put a 20G on a car thats still running stock pump and injectors?

 

[4g63awdtalon]

hey badgsx i dont think thats the question he asked....so leave your comments out. but i am sure he wants to upgrade from the t-25 and didnt want to mess with 14b, 16g, evo316 so he got a bigger one, i am sure he will upgrade soon enough.

also on the compressor housing of a regular 20g there is a spot to run a boost controller that could be leaking. do a boost leak test on it and that should tell you exactly where it is

good luck

 

[dsm]

i dont know if its a new turbo but my old hrc s16g the wastegate flapper inside broke and it woulndt let me boost more than 5psi or so. also check connections with the boost controller but i doubt thats the problem, those turbos come with a 15psi actuator OR 10PSI, i never got mine to boost lower and when it did thats when i found out that problem with the wastegate flapper.

 

[Phatty95GSX]

I think the wastegate is the problem... because it doesnt move like my stock one did, how did you fix that problem thats what some friends of mine said.... the wastegate flapper was probably broken ... anyway to convert to external wastegate?

 

[badgsx]

It was just a simple question 4G63awdtalon. Its just not a common thing to see a turbo that big on a car with a stock fuel system. I certainly dont think I asked it in a rude way. But Im pretty certain I didnt ask you a damn thing so I dont know why your anwsering me.

 

[Phatty95GSX]

The answer to your question badgsx.... I have some 660cc injectors and a walbro 255lph fuel pump.... put the turbo on knowing i wasnt going to boost more then the wastegate can allow atm... I was waiting on my boost controller thats why i didnt install, and i dont want to install my injectors / fuel pump if its only gonna spool 5psi, until i fix that problem and can adjust my boost with my controller im not puttin the upgraded fuel system in. now, if anyone knows how to convert the setup to external wastegate, like the tial 44mm... fill me in, i need this wastegate problem fixed. Thanks

 

[dsm]

i bought a new exhaust housing, only choice unless its still under the yr warranty, u can take it off with out having to undo all the coolant lines and oil.

 

[Phatty95GSX]

new exhaust housing as in o2 housing? or the turbo housing.. the thing the wastegate connects to?and where woiuld i find one for an external 3wastegate? let me know

 

[1fast97gsx]

new exhaust housing as in o2 housing? or the turbo housing.. the thing the wastegate connects to?and where woiuld i find one for an external 3wastegate? let me know

for an external wastegate you have to have the flapper from the internal wastegate welded shut on the exhaust housing of the turbo...

 

[Phatty95GSX]

my other o2 housing wouldnt fit on this turbo because the little circle the side of a quarter about.... was welded shut wher eyou can see the flapper thing open / shut... so is it already hooked up for external wastegate?

 

[TSI4PSI94]

I have a super 20G turbo... it can be a little confusing at first, but dont worry. The wastegate is actually routed through the same hole as the turbine outlet. All of the exhaust gas comes out through the turbine outlet, regardless if it passes through the wastegate or actually hits the turbine wheel. You're supposed to buy HRC's 2.5 inch O2 housing with the turbo so it will mate correctly; I did, and i have no boost creep and amazing flow. I run only about 16 PSI boost so i know that the wastegate works correctly.

 

[dsm]

yea housing from the turbo.