T04z With 0.6 Rear Housing On Rb26

[GETSET]

Just wondering what the thoughts are on this - would this create boost at 3000rpm or would it just not work? looking for about 380awkw with all necessary supporting parts.

All input greatly appreciated

Cheers

TBB

[meet07]

This is what a freind told me when I asked why he swicthed from a gt30 to a big turbo like the T04Z...I was kinda shocked of his response..this is on a rb25. I think it may be built.. Hope this helps!!

"Power wise there are a few t04z's in good combo's making 800+hp.

I went from GT30 which was like a light switch into boost and not easy to drive to a GT35, i was diapointed by the GT35's added lag and lack of top end punch and thus went to T04z in full twin scroll, in 3rd, 4th or 5th i make 2bar boost by 4200rpm and I rev to 8500... this is a massive power band, even in 2nd im making enough boost ligth up the 285 RE55's by 5000rpm still leaving it with 3500rpm of power band. My main reason to go T04z was that i circuit race more than anything else and the progresive nature and smooth spool up of the T04z make it much easier to control than the "hair trigger" smaller turbos. Most of my video i have of the T04z is just mess around stuff, I have video of it on the hub dyno putting out close to 600kw/788hp at 2.25bar boost, that said most of my usage is at 1.2 1.3bar where the car is very easy to drive."

[TiTAN]

i wouldnt reffer to a T04Z on a stock capacity 26 as responsive, if you want boost at 3000 look into a GT3076 with a 0.82 rear however on 98 pump fuel it will be limited to ~320rwkw.

any particular reason you want 380kw?

[R31Nismoid]

380kw or 380rwkw?

380rwkw - .60, forget it. Not a chance unless using race fuel

380kw - 320rwkw.. again, shit up a hill.

A T04Z front end is capable of over 400rwkw. To even let it enter discussion below that level is pointless.

i wouldnt reffer to a T04Z on a stock capacity 26 as responsive, if you want boost at 3000 look into a GT3076 with a 0.82 rear however on 98 pump fuel it will be limited to ~320rwkw.

any particular reason you want 380kw?

Agreed.

[rasonline]

it's amazing what a diff there is between 2.8l and 2.6l in terms of spool up. RB30 as well. T04z - my best guess is around 3,600rpm not 3,000rpm

[GETSET]

Thank you for your kind words

380awkw is 380awkw - on a 4WD

i have been given a T04z off a sr20 hence the 0.61 rear housing i am aware of other logical turbo choices to acheive my desired power output) - but this cost money

i have noticed the 1.0 rear housing is the way to go on rb26 to see over 400awkw

When you say not a chance unless on race fuel - what is the reasoning behind this? greater oxygen for combustion? it still comes out the small exhaust housing?

My concerns are surge?

My thoughts are - if a 6 cylinder is boosting this thing it should come in alot earlier - such as 3000rpm? obviously there would be a trade off - ie top end? hence 380awkw would be wishful thinking

I dont really care if you think this would be a pointless discussion - at least i will understand the reasonings behind different exhaust housings and possibly what may eventuate.

i am currently making 320awkw on twin trust turbos and i am contemplating whether this would be feasible upgrade

Cheers!

380kw or 380rwkw?

380rwkw - .60, forget it. Not a chance unless using race fuel

380kw - 320rwkw.. again, shit up a hill.

A T04Z front end is capable of over 400rwkw. To even let it enter discussion below that level is pointless.

Agreed.

[GETSET]

This is what a freind told me when I asked why he swicthed from a gt30 to a big turbo like the T04Z...I was kinda shocked of his response..this is on a rb25. I think it may be built.. Hope this helps!!

"Power wise there are a few t04z's in good combo's making 800+hp.

I went from GT30 which was like a light switch into boost and not easy to drive to a GT35, i was diapointed by the GT35's added lag and lack of top end punch and thus went to T04z in full twin scroll, in 3rd, 4th or 5th i make 2bar boost by 4200rpm and I rev to 8500... this is a massive power band, even in 2nd im making enough boost ligth up the 285 RE55's by 5000rpm still leaving it with 3500rpm of power band. My main reason to go T04z was that i circuit race more than anything else and the progresive nature and smooth spool up of the T04z make it much easier to control than the "hair trigger" smaller turbos. Most of my video i have of the T04z is just mess around stuff, I have video of it on the hub dyno putting out close to 600kw/788hp at 2.25bar boost, that said most of my usage is at 1.2 1.3bar where the car is very easy to drive."

interesting comments - the setup will be circuit orientated as well, does the progressive nature of the power spool equate to better times or loss times around a track

[R31Nismoid]

.60 rear would choke it down to probably 300-330rwkw give/take - it's hard to pin exactly.

The T04Z is a 800-850hp compressor, with a rear end that isn't going to flow much at all. It would have been restrictive on the SR as well. I would have thought a larger housing would have been used. Silly to put a Z on a SR with a .60, much better combinations out there for the money.

A .60 is virtually what a gts-t hi-flow is to give you an idea. Most of them peak out around 260-280 give/take.

Which trust items do you have on there currently?

Unless you just buy a larger rear housing for it I don't think its going to be an upgrade at all. Lot of cost & expense for nothing.

It could also surge indeed with a small rear like that, it'll be turning the front end very early so you might have minor surge issues in lower RPM's as boost builds - i had a similar issue with a GT30 with the largest comp wheel. about 2000rpm every so slight which hurt boost build a tad and a tiny bump in the ramp up on the graph (we guessed about 200-300rpm by the graph)

Comments on race fuel etc was as you were thinking. Same volume on the out, just better combustions going on inside for that amount of air.

side note - rwkw/awkw same thing for GTR's really (i assume you are talking GTR here). It's not a full time 50/50 split like other 4WD cars.

[R31Nismoid]

interesting comments - the setup will be circuit orientated as well, does the progressive nature of the power spool equate to better times or loss times around a track

If you are going circuit then you don't want a t04z unless you need big numbers.

I totally disagree with meet07's friend or whatever about the GT30. My setup was excellent and power came on nicely. Not uncontrollable at all.

The t04z would come on with a hard rush which you would think would make it harder to drive.

Friend of mine pulled OFF a t04z and went back to twin low mounts for this reason.

[paulr33]

am i missing something?

why not just tune the car and set it up better so that the GT30 setup is more progressive and controllable ?

[The Dan]

As Ash said, the 0.60 rear will choke it too much. I would be surprised if it saw over 330awkw.

As for spooling earlier due to being 6 cylinder, that is nonsense. An SR20 will spool that turbo exactly the same as your RB26 will. It has to do with exhaust pulses and the amount each cylinder displaces each stroke.

Also, Ash - T04Z is only rated to 750+hp which is a very generous 800 engine hp if you were really lucky and pushing boost over 2 bar.

[The Dan]

am i missing something?

why not just tune the car and set it up better so that the GT30 setup is more progressive and controllable ?

Don't be silly! that would be too easy

[R31Nismoid]

As Ash said, the 0.60 rear will choke it too much. I would be surprised if it saw over 330awkw.

As for spooling earlier due to being 6 cylinder, that is nonsense. An SR20 will spool that turbo exactly the same as your RB26 will. It has to do with exhaust pulses and the amount each cylinder displaces each stroke.

Also, Ash - T04Z is only rated to 750+hp which is a very generous 800 engine hp if you were really lucky and pushing boost over 2 bar.

i was in the ballpark lol

I know GT35's are 700hp - 380rwkw or so - took a stab around 800hp being you can make 440rwkw off a Z if you wanted to.

Probably could have googled... to much effort though

[The Dan]

i was in the ballpark lol

I know GT35's are 700hp - 380rwkw or so - took a stab around 800hp being you can make 440rwkw off a Z if you wanted to.

Probably could have googled... to much effort though

Yeah, with turbos it's never really exact anyway. That's why they say 750+. Your 800hp guess is not inaccurate

Generally with a T04Z running 26-28psi I have seen them touch on 500rwkw almost. 475rwkw on Gervase's RB26 with a 0.8 rear and 494rwkw on Michaels RB26 with a 1.0 rear both running about 26-28psi.

You don't tend to make too much more than that on a Z though. With that 0.6 rear this guy is talking about, I reckon he might be able to force it to 380rwkw with very high boost but it is going to generate a lot of heat in the process and the turbo is going to suffer as a result.

[R31Nismoid]

Ye same, i don't think you'd even be able to push that much out.

It'll be det'in like crazy due to the backpressure and then the heat as well as you say, similar to having a blocked cat - will only make so much power and anything more goes nowhere.

I'd like to see it done though just for shits and giggles aint my motor

[W0rp3D]

i have been given a T04z off a sr20 hence the 0.61 rear housing i am aware of other logical turbo choices to acheive my desired power output) - but this cost money

Here is a reallity check for you, there are 3 options below but you can only choose 2 of them:

1) cheap

2) reliable

3) fast

Pick any combination of two and the third one is not possible.

Edited December 12, 2009 by W0rp3D

[GETSET]

Ye same, i don't think you'd even be able to push that much out.

It'll be det'in like crazy due to the backpressure and then the heat as well as you say, similar to having a blocked cat - will only make so much power and anything more goes nowhere.

I'd like to see it done though just for shits and giggles aint my motor

that is what im afraid of - it would be interesting to see whether anybody out ther has experienced a change in exhaust housing and have dyno graphs to show. I have seen this done with a sr20 with a 1.0 to 0.8 to see a much more responsive turbo.