GT30r vs GT35r on RB25det need help deciding

[zachariah]

what do yo guys think i should i run on my rb25 a 30r or 35r and how much power can my rb25 stock internals take any help would be awesome thanks!

[Burglervr6]

what do yo guys think i should i run on my rb25 a 30r or 35r and how much power can my rb25 stock internals take any help would be awesome thanks!


If you want response go 30R, and with supporting mods you can make 500+ to the crank

If you want more top end and power go 35R, and you wont have to sacrifice tooo much response.

I'm currently doing my swap (Rb25det w/35R) and aiming for about 400rwhp. Your best bet is to check out the Aussie forums because they know their shit and have all the info you could ever want and need.

[jspaeth]

If you want response go 30R, and with supporting mods you can make 500+ to the crank

If you want more top end and power go 35R, and you wont have to sacrifice tooo much response.

I'm currently doing my swap (Rb25det w/35R) and aiming for about 400rwhp. Your best bet is to check out the Aussie forums because they know their shit and have all the info you could ever want and need.

What? RB25 with a 35R......you should be able to put out WAYYYYYYYY more than 400.

[mayco_86]

What? RB25 with a 35R......you should be able to put out WAYYYYYYYY more than 400.

I agree. He should be able to put over 500 whp.

[zachariah]

yeah i have a seen a guy make 500 wheel with stock internals on a 35r and he even had a stock intake plenum. can an rb25 handle 500whp on stock internals or is that not a good idea?

[HYPNOTIK]

95% of this depends on the tune. I know of several 600+hp RB25's on stock internals but it all depends on the tune.

[Walperstyle]

19 years old? wanting to keep stock internals. This sounds all to familiar. You have access to the tools necessary to do a full rebuild of a Rb25? If the answer is no, then I wouldn't chance stressing out an engine being each engine is different. If a previous owner didn't maintain his oil properly, or the oil pickup was damaged and dirt got in around the mains, you could be looking at some serious issues with the internals. Its a big IF, and whenever you are stressing an engine, you just bring more variables into the mix. Big Horsepower guys usually start from the bottom up and make sure everything is couture

If you are going to go big, do it right, and do it the first time.

[nsn240]

19 years old? wanting to keep stock internals. This sounds all to familiar. You have access to the tools necessary to do a full rebuild of a Rb25?

Bingo.. that's a big chunk of change for a 19 yr old.
Either way, I'd run a twinscroll 35r no questions
And like everyone else said it all depend\s on the tune.

[zachariah]

yeah thats what i want to do is a 35r but i cant afford to have everything built from the bottom end up right now, would i just make more sense to run a 30r for now and try and make around 440 wheel later do the 35r when i can afford a build to make sure nothing gets messed up and ends up costing me more money?

[coreansurfer]

fail. do it right, do it once

[blkwrx]

fail. do it right, do it once

yeah i get that makes sense it will just take me to long to afford all that i would rather have decent amount power in the mean time before i can get the money to build the motor.

[coreansurfer]

yeah i get that makes sense it will just take me to long to afford all that i would rather have decent amount power in the mean time before i can get the money to build the motor.

if you are moving from stock sr or ka to rb, the power boost will be sufficient until you can save up for an hta twin scroll gt35r

[zachariah]

if you are moving from stock sr or ka to rb, the power boost will be sufficient until you can save up for an hta twin scroll gt35r

yeah i could understand if i was but i have an r33 skyline i have had for probably a year now, and before this car i had a s14 fully built 2.2L sr with a twinscroll gt30r. and that was extremely fast so now my rb feels prety slow. but i guess winter is coming in my area so maybe il just start saving up

[zachariah]

so if i wanted to shoot for the power goal of around 470whp what turbo upgrade and stuff would you guys recomend me running? is that possible on a gt3076r?

[MURPHY]

What other mods? I have a series 2 I'm putting a 35r on with boltons.

[zachariah]

What other mods? I have a series 2 I'm putting a 35r on with boltons.

i would have pretty much all supporting mods and cams. are you going to going run cams and whats your power goal?

[Zacho]

Thought I would add my input,

I pulled off my head to put in the proper oil restrictors (1.25 rear, 1.5 front iirc), and I put a new OEM HG in place. Because I will be tuning it myself, I'd rather have the HG as the weak point vs. something else, for who knows what may happen. I used ARP studs, engine has an N1 water pump, new timing belt, new valve seals etcetc. I have faith in the stock 25 bottom end, after reading the SAU forums for hours on end I think you have to take what they say with a grain of salt, and take into consideration the purpose of your car.

Anyway, my setup will be a 3076R with the .82 rear housing on a 25. Going for about 375-400 rwhp. I'm just waiting on engine management/downpipe to get finished and I can fire it up.

How long your 25 lasts seems to be very dependant on your tune. So I would reccomend to not skimp out on management. I also conclude from a lot of reading this: The rb25 seems to be pretty solid at 400rwhp with a good tune. Once you start going past that, it gets more questionable. However we could argue all day long what it "really" is capable of I decided to find out for myself. So time will tell.

The kicker....I'm younger than you ;). Good luck. Let us know what your plans are.

[zachariah]

Thought I would add my input,

I pulled off my head to put in the proper oil restrictors (1.25 rear, 1.5 front iirc), and I put a new OEM HG in place. Because I will be tuning it myself, I'd rather have the HG as the weak point vs. something else, for who knows what may happen. I used ARP studs, engine has an N1 water pump, new timing belt, new valve seals etcetc. I have faith in the stock 25 bottom end, after reading the SAU forums for hours on end I think you have to take what they say with a grain of salt, and take into consideration the purpose of your car.

Anyway, my setup will be a 3076R with the .82 rear housing on a 25. Going for about 375-400 rwhp. I'm just waiting on engine management/downpipe to get finished and I can fire it up.

How long your 25 lasts seems to be very dependant on your tune. So I would reccomend to not skimp out on management. I also conclude from a lot of reading this: The rb25 seems to be pretty solid at 400rwhp with a good tune. Once you start going past that, it gets more questionable. However we could argue all day long what it "really" is capable of I decided to find out for myself. So time will tell.

The kicker....I'm younger than you ;). Good luck. Let us know what your plans are.

hey thanks for info man i appreciate it im definately going to spend some time thinking about what to do with it. i saw one guy with the same setup as your going to do stock bottom end with cams he made 433whp and 351tq i just dont if i would be happy with that but who knows if i do go for big power i need to do it right.

[Burglervr6]

hey thanks for info man i appreciate it im definately going to spend some time thinking about what to do with it. i saw one guy with the same setup as your going to do stock bottom end with cams he made 433whp and 351tq i just dont if i would be happy with that but who knows if i do go for big power i need to do it right.


Power is nothing without control and the ability to get it to the ground. And as for the my 400whp mark....that is DD boost. I never stated my high boost numbers. In terms of mods, I plan on a stage 2 valvetrain, springs/cams, port and polishing, and a tomei headgasket (lowering CR). Not to mention a snow performance system as insurance. The headwork won't be until spring. As for now I am working on acquiring a PowerFC and 810cc injectors/fuel rail.


Either way, like others have stated read the SAU forums, Nicos RB forum and on here. There are ALOT of resources at our disposal so their is really no excuse.

[driftrb25det32]

What? RB25 with a 35R......you should be able to put out WAYYYYYYYY more than 400.

Im running ballbearing 3540 with 82r housing on rb25det gtr injectors making 360hp on 1bar very responsive full boost by 3500 same turbo making 410hp on friends rb30det same boost

[jamg]

look into borgwarner EFR turbos.

they actually perform better than garrets.

http://www.full-race.com/articles/borgwarner-efr-turbos.html

[jr_ss]

Dude, you bumped a 5yrold thread to add your two cents. Next time pay attention to post dates.

[Clicky]

^^^^^^ hes pissed