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Thinking of replacing my hiflowed turbo to a GT35/40R 0.70 / 1.06 internally wastegated turbo.

Has anyone else done this conversion and can you advise the handling ie lag, dyno results, drivability, when boost comes on etc.

Currently do drags and circuit in SII GTS-T with intercooler, Power FC, Hiflow injectors, Z32 airflow meter, fuel pump, fuel pressure reg etc. - acheiving 302hp in third gear dyno. Would really appreciate hearing from someone who has gone through the exercise - good or bad???

Cheers

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I have been doing alot of research on this (haven't done it though) but in alot of cases, I wouldn't go for the 1.06ar exhaust housing, due to MASSIVE lag on a RB25.

I have a friend that has this turbo on his 95 supra (3.0l) and it hits full boost at 4200rpm. A guess at full boost on a rb25 would be 4500 - 5000rpm!!!

Thats way too much lag for me. I'm not an expert, but thats my opinion.

I hate lag, so I am going to eventually purchase something with a .63ar exhaust. If you are looking at big power, I'd go a .83ar exhaust.

Not sure on the Compressor size though..

SK might have an idea if he reads this thead.

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over 5k IMO

its bigger than my GT30 (4200rpm/16psi) and then your going bigger again on the Exh housing.

get a .82 and it'll be much nicer. Id even say a GT30 like mine. Its awesome for all forms of use

Hi Nismoid,

Thanks for the feedback. I was trying to keep the internal waste gate due to simplicity, cost etc. but seem to be only able to get the thing in a a/r1.06 exhaust. comp is a/r 0.7. I'll do some research on the GT30. Can you tell me your dyno result atrw and qtr mile times...much appreciated

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I have been doing alot of research on this (haven't done it though) but in alot of cases, I wouldn't go for the 1.06ar exhaust housing, due to MASSIVE lag on a RB25.

 

I have a friend that has this turbo on his 95 supra (3.0l) and it hits full boost at 4200rpm. A guess at full boost on a rb25 would be 4500 - 5000rpm!!!

 

Thats way too much lag for me. I'm not an expert, but thats my opinion.

 

I hate lag, so I am going to eventually purchase something with a .63ar exhaust. If you are looking at big power, I'd go a .83ar exhaust.

 

Not sure on the Compressor size though..

 

SK might have an idea if he reads this thead.

Thanks mafia,

I'm very concerned about lag as well... as I use the car on the circuit and need quick response as well as long legs in the straight. I want the best match for the engine capacity but am finding it very difficult to get a straight, independent answer...hence why I'd like to get feedback from anyone whose fitted an ungrade turbo and their actual results

Cheers

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so far, the all hailed shootout mode

330rwkw with a hybrid mix of fuel, not just normal PULP on 24psi

made around 270rwkw without the fuel and 17psi

and the show is on well and truly around 4200rpm-4500rpm.

Best match is the GT30 for an RB25, if you want bigger power then a GT35 is the go but it comes at a cost, and mine is quite nice on the street

Im heading for some drag this friday so i'll have a rough time/mph then

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Stealth,

Have you considered importing a HKS GT2835ProS (270-280rwkw) or HKS 3037ProS (300-320rwkw) from japland? They are both Internal gate. hence the PRO

Form memory they are around the 2.6k mark, unsure exactly the extra tax's and crap on top. I did look in to it a while back and have since forgot.

I 'think' stamp duty is only 3% on turbo's then you pay the GST. or is it the GST first then the stamp duty on that. :D

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my mate and i have just finished a conversion in his vl. its an rb25 with a gt35r/1.06 rear.

the engine is standard except for tomei poncams,splitfire coils,xf throttle and fuel and computer obviously.

it is running through a vl turbo 5 spd.also a 3:45 diff ratio

the engine makes 20 psi by 4200rpm and is producing 313rwkw.

personally i would recommend the .84 rear housing and a 4:11 diff

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