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Hey mate,

Im was running that turbo with a .64 on an RB20det. It was laggy as all hell, but of coarse it will be different on a 26. I am now about to run this turbo on an RB25 which should run reasonably similar to yours. A few tuners have told me that i will not be dissapointed with the spool rate and that i should hit full boost by about 4000 rpm which is decent in my opinion.

cheers

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Hey mate,

Im was running that turbo with a .64 on an RB20det. It was laggy as all hell, but of coarse it will be different on a 26. I am now about to run this turbo on an RB25 which should run reasonably similar to yours. A few tuners have told me that i will not be dissapointed with the spool rate and that i should hit full boost by about 4000 rpm which is decent in my opinion.

cheers

I would think with a .64 housing u should see full boost a lil earlier then that on a rb25 but yeh I could emagin it would have been laggy as hell on a 20.

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Full boost.. 5psi or 24psi? Depending what full boost is the 'full boost' RPM can vary by 500-1000rpm depending how its loaded up.

Generally for 18-20psi, .6 earlier than 4k on an rb25.... Not unless you hold it on the brake for 10seconds or its an Auto.

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sorry, to be more specific i was refering to on the dyno. 4th gear at 15psi, ive been told by a few tuners that 15psi (full boost) could be seen at about 4000rpm maybe a little sooner.

Not sure what to expect really, i dont have that much experience with turbo's yet to be honest. Just given a heads up as to what i was informed.

Cheers

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15 psi by 4500 on an rb26 sounds really laggy to me.

I had an .82 gt3540 on my sr20 and could get 15 psi by 4400 no problems.

It was a built motor with cams but you would expect the 30 % extra capcity of the 26 to well beat the SR20.

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4400rpm sounds very similiar to the sort of spool a bloke was getting on his SR20 over on ns.com making 320rwkw but that was a GT3076r .6. :S

A mates Rb25 with a GT35 .82 see's all 20+psi by ~4200rpm. BUT thats behind an Auto.

.82 GT35 + SR20 = 4400rpm. Hrmm..

RB26 will be fine with a GT35 .82; they have the rev's with little modification.

Spool is subjective; the dyno type also has an influence on how it loads the motor up and for how long. Some dyno operators load it up from idle; others sit it on the brake for a sec to show a nice early spooling meaty curve.

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Ive made my mind up .82 its is! its a r26 for crying out loud! if an sr can hit 15psi buy 4400rmp them im sure my 26 will have no problems at all with spool! its a built motor aswell, thanks guys now my next question is who has a GT35 with a .82 housing for sale lol

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.82 would be perfect for an rb26. I had a 35/40 .82 on my rb25 in a vl, manual and it was pretty responsive, perfect for the street i'd say. If you went the .6 rear housing you'd deffinately be lacking the top end.

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Size the turbo to what power you want.

The .6 GT35 will get you between 300 and 350rwkw. The .8 closer to 400rwkw maybe over if really leaned on and the 1.06 a bee's docker over 400rwkw.

There's no such thing as lack top end; if it makes 350rwkw it makes 350rwkw; be that with a .6 or .8 top end will feel the same but the mid range will definitely not.

I must suck.. I've driven RB25/30's with GT35 .82's and I feel they are only 'just' bearable on the street. IMO a street Rb25/30 is awesome with a GT30. Not because I own one but because I've driven a few different setups. I'd expect the .6 GT35 to be very similiar to that of the .8 GT30 BUT with additional decrease in response due to the larger wheels/inertia that affects primarily the lower 1st and 2nd gears.

If you throw an auto in to the equation then most definitely the GT35 .82. But 5speed manual, I don't like the lack of response feel from the GT35. I guess you get used to it. :S

For the track I'd prefer the GT35 .8 simply because the GT30 .8 I think will be pretty damn hard to get out of the corners clean due to its quick spool and big hitting mid range. Of which makes the car fun on the street. :)

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