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What turbo upgrade for rb25 in gu patrol

Gu rb25

By Gu rb25,
in Engines & Forced Induction

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Gu rb25 Rookie

Gu rb25

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Hi guys new to this forum thing but need your help with choosing some new upgrades :D hoping you guys can point me in the right direction.

Ive recently completed an engine conversion on a 98 gu patrol went for something a little more exciting then the 2.8td that was in it instead with a rb25det that i had from a previously  crashed r33 of mine, the engine is unopened and has very basic mods so far but im keen to change that very shortly. 

Im looking for a turbo upgrade at the moment but ive got limited experience so not really 100% sure, but ive been contemplating the mambatek gtx3071r the company seem to have fairly good reviews for the small amount i can find, but im just not sure on the turbo choice and rear housing choice either .63 or .82 so any help would be appreciated.

Due to the fat arse patrol the poor little rb has to push around now im hoping for something not to laggy and capable of about 350rwhp 

 

Thanks in advance :1311_thumbsup_tone2:

admS15 Grand Master

admS15

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For 350rwhp/260rwkw, my advice would be to get your stock turbo high flowed by hypergear. That turbo will do 260rwkw and full boost b4 3500rpm. Not too sure about the mambatek. Not many results around with those. I know they sound attractive but you will be a bit of a guinea pig.

Gu rb25 Rookie

Gu rb25

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Ok cool i did look at the highflow stuff a little but thought it might be worth getting something a little bigger so ive got some headroom for later chances are once i get 350 I'll want more:D dont really want to pay twice but i might have a chat to the hypergear guys aswell.

 

Dont mind being the guinea pig with the mambatek stuff its just hard to know what mods to do as the rb obviously delivers its power different in the patrol with all the wait and im also run a extremely heavy flywheel hoping to gain some low down torque but it messes with the top end a little

Gu rb25 Rookie

Gu rb25

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If i was buy a motor i probably would of went with that( and i just really wanted to start driving it, took a little longer than i wanted to do the conversion) as they make some good low down power but i had the rb25 already running read to drop in so thought id see how it went first before i went the rb30/25 way also ive never looked at whats involved but im guessing it might be more then i could do myself would definitely be good though.

I am still suprised at how well the near stock rb is going with the amount of weight its pushing around though

 

hypergear Grand Master

hypergear

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For your application might not necessarily have to build an Rb30det, we can high flow your factory turbo to meet your goal. and it will be very responsive for the power it makes. 

Gu rb25 Rookie

Gu rb25

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Ok i would definitely be interested in the highflow option if i can get around the 350rwhp out without squeezing  every drop out of the turbo.

I have to put a ecu in over the next few weeks hopefully and get a tune on the standard turbo i seem to have lost some top end rpm with the massive flywheel (im guessing) so that might make me go the highflow more than the gtx3071r if ive cut the top end out it probably wont be worth looking at the gtx 

hardsteppa Grand Master

hardsteppa

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2 hours ago, admS15 said:

 he has developed plenty of turbos for the rb for you to choose from.

this is why I rate hypergear, very happy with their hiflow i'm currently running. Plenty of good turbos around, but tailored specifically to rb's , well...worth supporting someone that puts so much R&D into a specific application.

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admS15 Grand Master

admS15

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Ok i would definitely be interested in the highflow option if i can get around the 350rwhp out without squeezing  every drop out of the turbo.

I have to put a ecu in over the next few weeks hopefully and get a tune on the standard turbo i seem to have lost some top end rpm with the massive flywheel (im guessing) so that might make me go the highflow more than the gtx3071r if ive cut the top end out it probably wont be worth looking at the gtx 


A r33 high flow will get you there close to maxed out on 98, on e85 it will make 400+rwhp. A r34 high flow will get you a bit further. I'm not sure what effect being in a patrol will have with your heavy flywheel and whatever diff gears they have. Hopefully someone who has done a similar conversion can chime in on this.

Also the mambatek gtx turbos can't be compared to a genuine Garrett gtx turbo. I've seen a result for a gtx3076 mamba on a rb25 neo and from what I remember, it was very laggy and still fell short of a Garrett in the top end. Got to compare apples with apples and mamba results are far and few between.
Gu rb25 Rookie

Gu rb25

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Ok the e85 is this the flexi e85 at servos or a race bend? I dont know much about it.

Yeah i thought the mambas  wouldn't be as good consideeing there half the price but i havent had a great deal to do with turbos so i didnt think it would be alot if its a copy but like i said im new to this.

I'll have a look at the hypagear web site now:14_relaxed:

Gu rb25 Rookie

Gu rb25

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I didnt think of using the rb30 one i went with the rd28 flywheel, but it seems to have knocked the top end rpm around ive got to dyno it yet but seems to finish up around 6000rpm but a tune might help

Its not as bad as u would think on fuel i got 16l  per 100 thats with 3 days of beach work and a split highway and around town for the rest and i was giving it a hiding only on 11.5psi though

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