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Im looking into building a approx 400rwkw RB30 for tarmac events, track days, and street use.

I was wondering on the best (performance and value for money turbo, and wastegate size).

Alot of people recommend the GT35r, but they dont seem to make the numbers? and that is confirmed by my rough fugures on the compressor maps (i could be very wrong).

I would prefer to use garrett as i can get them reasonably cheap - oh and i dont want to run to much boost, over 20psi say as i only have access to 95octane gas.

Also, is a 38mm wastegate suitable or do i need to use a 45-48mm size bearing in mind the later is generally twice the price.

cheers

rob

do you know that 400rwkw is about 536hp, dont thing there is any turbo on the market that will produce that power on or under 20psi and still be streetable, especially on 95ron fuel. suggest you be a little more realistic with power figure, say 300kw. Can make this power with GT35/40 with 1.00 or 1.06 rear with other supporting mods safely on pump on mild boost. 38mm gate will be ample for this combination. If you go bigger like a Gt42 or TA45 you may need to step it up to a 48mm or 50mm gate. but these turbos are designed to be boosted hard. They really dont work efficiently on lower boost pressures and you are still stuck with the lag factor. Good luck with it.

Im looking into building a approx 400rwkw RB30 for tarmac events, track days, and street use.

I was wondering on the best (performance and value for money turbo, and wastegate size).

Alot of people recommend the GT35r, but they dont seem to make the numbers? and that is confirmed by my rough fugures on the compressor maps (i could be very wrong).

I would prefer to use garrett as i can get them reasonably cheap - oh and i dont want to run to much boost, over 20psi say as i only have access to 95octane gas.

Also, is a 38mm wastegate suitable or do i need to use a 45-48mm size bearing in mind the later is generally twice the price.

cheers

rob

Edited by BezerkR32

Why cant you get better fuel?

If I wanted response for track days etc I'd use low mounted 2530's or mabye N1's.

GT30? (one of the bigger ones) Dunno if it can do it on low boost but.

do you know that 400rwkw is about 536hp, dont thing there is any turbo on the market that will produce that power on or under 20psi and still be streetable, especially on 95ron fuel. suggest you be a little more realistic with power figure, say 300kw.

I agree.

Relating to the wategate sizing part of the question, there is a link in the sticky "Guide" :D

http://www.skylinesaustralia.com/forums/in...=43638&st=0

Hmmmmmm………

3 litre (not a 2.6)

400 rwkw (not 450 rwkw)

20 psi (ouch)

Track work (yep)

Response (tricky)

Hmmmmmm………

I reckon you would just about satisfy all of those with a T04Z

But you are going to need to very carefully select your compression ratio, head work, camshaft duration and lift. Then its down to tuning, tuning, tuning.

:D cheers :D

PS; tip, get some toluene and get that ron up, make the job a lot easier.

Thanks for the info guys, im limited to 95ron as im in NZ, and they dont seem to give a stuff about the quality of fuel the give us... are octane boosters worth using?

I realise 400rwkw is a bit optimistc, but its been done here many times before, see R.I.P.S skyline.

SK, i was planning on using a GTR head with standard cams and maybe adjustable gears, with a CR of 8.3 to 8.5... sound doable?

What A/R and trim T04Z should i look for???

cheers

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