Rb26 With A Gtx3071 .63

[lozz_ti]

Hey,

Im sure this has been covered before but I cant find any info can some one point me in the right direction please.

Atm I have a pretty much stock r32 gtr with a link v4 ecu and a dump pipe back exhaust. I have a gtx3071 off my other car that has a .63 exhaust housing on it and im thinking about throwing it on a cheap manifold and maxing out the injectors and seeing how it goes. If it works ok then I will go bigger injectors, fuel pump, pressure reg, e85, 6boost manifold maybe a bigger exhaust housing .82 or 1.06? etc..

The question I want to know is am I wasting my time putting this turbo? Should I just save my pennys and go for something else? Any recommendations?

Any real info would be much appreciated, cheers, lozz

[Guilt-Toy]

it would be a awesome street setup! even with the small rear housing

[lozz_ti]

Im keen to do the odd track day aswell but it will be mainly street. What sort of power would be achievable with that size exhaust housing and a fuel system to support e85?

Cheers, lozz

[wolverine]

Mick_o made 335rwkw (unigroup dyno) with a 0.82 on E85 so somewhere around there is a fair guess.

A bit less power with a 0.63 but would liven up the bottom end a fair bit.

[PN-Mad]

My SR20 is making 290kw on 98 with a GTX3071 0.82 on 18psi ext gate. MickO was I/G wasn't it?

If you get your hands on a 0.82 housing and I think you'll have a nice 300-340kw car without pushing too hard.

[lozz_ti]

Thanks guys I will throw it on and if it works but i want more power than I will up the exhaust housing and see how that goes. At the moment it is an internally gated housing but if I go bigger I will get an external gate housing

Cheers, lozz

[Mick_o]

336kw mate

Mick_o made 335rwkw (unigroup dyno) with a 0.82 on E85 so somewhere around there is a fair guess.

A bit less power with a 0.63 but would liven up the bottom end a fair bit.

[discoPumpkin]

so u will put it on to c if it works and then tear it back down to change to a 6boost + external gate

u must like either work'n on yo car lots or payin a mechanic mega bux

[scotty nm35]

^^ Reading that gives me a headache.

On topic, I made 341kw on the gtx3071 with 1.06 Tial, at 30psi maxing the compressor. This was through an auto running stock a VQ25det, stock cams, stock manifold.

[discoPumpkin]

^ get some panadol 4 your headache or take a pregnancy test just to be on the safe side

Edited May 28, 2013 by discoPumpkin

[wolverine]

out by 1 lousy itty bitty kw

[34GeeTeeTee]

out by 1 lousy itty bitty kw

They all count

[lozz_ti]

I have a turbo off my other car. Cheap second hand manifold I can get for $150. And I have all the necessary bits and pieces to put it all together myself i cant see it costing to much. If I like the set up then I want to do it right. Eg good manifold and maybe go up a size in exhaust housing for more power

[GTScotT]

with a .82 ewg this would be pretty fun on the street.

Theres no harm in trying the existing housing if you can do all the work yourself, but I'm sure you will need to pay for a dump and other bits on top of the tune. It could prove costly.

consider getting yourself a manifold and .82 straight up. That way if it doesn't make enough power for you you can simply swap it for a larger GT30 based turbo and retune then. Bolt for bolt. Look at the recent FP 3076 HTA results for example.

that is how I would do it anyway.

[lozz_ti]

I have a dump pipe I just need to modify it a bit to fit my car. But I am happy to spend the money on the manifold and exhaust housing if I can do it once and do it right.

Can anyone tell what exhaust housing I should go for then if I want to get somewhere around 300kw maybe more if I run e85. other mods I plan on doing is injectors, fpr, fuel pump and maybe cams.

[34GeeTeeTee]

with a .82 ewg this would be pretty fun on the street.

Theres no harm in trying the existing housing if you can do all the work yourself, but I'm sure you will need to pay for a dump and other bits on top of the tune. It could prove costly.

consider getting yourself a manifold and .82 straight up. That way if it doesn't make enough power for you you can simply swap it for a larger GT30 based turbo and retune then. Bolt for bolt. Look at the recent FP 3076 HTA results for example.

that is how I would do it anyway.

Awwwwwwwww yeah!

[Roy]

I have tried a ~ 0.63 housing and a 0.86 housing on the same turbo and same engine. Made the same peak power but moved the curve a long way with far poorer response with the bigger housing. So if you are running E85 then go the smaller housing. If you are running pump the tune wont seem to handle the back pressure as well. If its a track car that is going to see sustained high revs and load then perhaps make sure you are not giving it a gob whack of boost when at the track like you can on the street.

I am now running a T67 with a 10cm (~0.74) housing but once a few things are fixed on my car will be gong back to the 8cm housing (~0.63) Thats on a 2.5L 6cyl

[scotty nm35]

There are drawbacks with smaller housings and larger ones. Just because your setup made no extra top end bumping up the housing size doesn't mean there is no benefit.

I noticed the transient response was better with the larger housing, torque should increase as should power if there are no restrictions, and obviously there will be less manifold heat and pressure. A couple of hundred rpm response lost isn't a huge price to pay. For a track car the larger housing is an obvious choice I would have thought.

E85 doesn't change the back pressure, it just masks the effects imo.

[Roy]

Thats my point. E85 masks the problems associated with higher than desirable back pressure. I agree that I preferred the way the 12cm housing performed on the TD06-20G on a 2.5L but 100% made for a slower car. The 8cm spooled up and hammered in a heart beat. The 12cm made for a lazier thing to drive which is a subjective like it or laothe it thing

The below graph shows all the same turbo. Its an RB20 with 8cm housing. Rb25 with 8cm housing and RB25 with 12cm housing. The 12cm housing tunes were pretty rough and ready and boost curves not stressed over. They were slapped on , minimal ignition and just initial power runs to see the characteristics of the turbos before swapping and changing setups and cams etc. But you could get a feel which way it was headed

Not all sized turbos and setups would give the same result...but for me a street GTR with occassional track work then I think based on my experience with the smaller TD06-20G and 8cm and 12cm housings I would go the smaller housing.

[Lithium]

Are those two setups exactly the same turbo? Probably irrelevant, GT30s and TD06s are quite different beasts - an RB25 (let alone an RB26) with a .82a/r GTX3071R would make an RB20 with a .63a/r GTX3071R look silly at every point in the rev range, I'd put money on it. I'd strongly suggest the .82 over the .63 in this case, personally.