Gt35r Vs Garrett T04z - Discussion (just Post In This Thread To Create A Database)

[Rezlo]

No probs, for a while I thought I was the only one here - design engineer/fea monkey that is.

One of the reasons I dont open my own shop :-) modding cars is much nicer as a hobby than a living... got 4 350kw+ sr20's done in the last 12 months all GT35 ha ha that excludes some non nissan projects.

[Jap_Muscle]

how large were all your exhaust systems when you made the 400kw?

did u guys run straight pipes? any cats?

[wallas]

what an informative thread, well done with the info chaps

[wrxkilla]

a very old quote but im slowly getting through the thread.

not that i dont believe you sky30 but i find it extremely hard to believe your making almost 400kw with a .86 rear......especially only on 20psi. that sounds like something a 5L motor would do.

im running a rb30 gt35r .86 @ 20psi only made 335rwkw. no head work as such but still....

do you have something to back that up? i do hope you prove me wrong because it gives me hope for my setup lol

i nearly made that on my rb26 with stock head and stock bottom end. bp ultimate, 20psi. Just cams.

i would expect your rb30 to make much closer to 360kw and maybe closer to400kw on 24psi ???

[tommis85]

Hey all, I thought I'd come back to this thread first and tell you all that I've had to convert my project back to factory twin turbo setup from a GT35r.

It was a very hard decision for me and here were a couple of reasons for this including me running out of money and also insurance problems lol so yeh, I will do a proper post in the selling section on SAU I guess. (I haven't tried selling on here before so am a bit unsure) I'll get up some photos too. Manifold and turbo, brand new, no more than 350-400km on it - don't laugh lol - it's been in the workshop more than at my place!

One of the guy on here mentioned a while back that he wouldn't mind seeing how a .63 exhaust housing performs as most the guys run the .82 rear end and yeh, it comes on hard at around 3800-4000 on a bog stock engine running splitfires, E11v2 and a 044. I had it dialed in at about 13 pounds from memory and it came on with a nice thump....a fair bit earlier than the 0.82 housing which I also ran before downsizing (for those who recall my posts in this thread).

So yeh, hope to post a proper thread up in the for sale section tomorrow ;-)

[tommis85]

Here's the add in the For Sale section.....anyone trolling through this thread looking for a brand new GT35r, please have a look here!

[Rezlo]

As I was saying earlier in this post, dyno's here suck,,,

Anything over 6000rpm even at only 1.7bar and set to boost up as slow as possible the sx roasted its 285's... made 428kw at 6100rpm with the T04z,

Going to be going up country in the next few weeks to use a hub dyno and do a run at a semi decent drag strip so I can try convert the 210kph trap speeds into somthing decent ET wise.

[Brockas]

Just got back from the workshop.

Compared my GT3582 setup (blue line) with a Cerbera's T04Z setup (green line), which were both run up on the same Dyno Dynamics dyno in shootout mode.

Not sure if Simon's had any issues, but my setup is strangled HARD in the top end. So much so, that adding 5psi and 2 degrees ignition timing gained me a whole 1hp up top. Did gain about 30hp through the mid range though, but I obviously have a large restriction in my inlet/exhaust which isn't allowing any more than 500hp flow.

Anyways, enough ricers excuses, here is the comparison:

Edited August 10, 2009 by Brockas

[discopotato03]

What sized turbine housing did the GT35R have ? No pun intended but the greatest difference between Diesel and petrol GT3582R's , center section aside , is the housings . Big GT40 suckers on the Diesel ones which is a size up from the T04 ones on T04Z's .

If Garrett were doing the GT3582R justice it would be in a large frame BB center section and in housings like the GT4082 or GT4088R's have . As they are the turbine housing is a bored out GT30 one and the cold side a T04S one .

The best you can do for a GT3582R petrol turbo is to use the largest 1.06 A/R T3 flanged one or a modified T4 International flanged T4 housing . I think ATP do a large flanged TS housing for them .

A .

[R31Nismoid]

Paul - I think its also struggling earlier on as well.

It is a bit lazy up onto boost, any idea what is causing that at all? Could be a double edge sword once you fix one end the other comes good.

If you have the peak of 24psi on around 30km/h earlier (115/116 as opposed to 140), it would make that mid range even more interesting in the GT35's favour.

Would be interesting to see just how much difference it would make too, definitely you would notice it just driving around if the difference is as good as i suspect it might be.

(just the assumption here as following on from the ramp up before it starts to build slowly from 21 to 23.5psi)

Were those runs same day?

[Brockas]

Cerbera's car has been parted out for about a year, so the T04Z run is a little old.

We're stumped as to why it's restricted. The only thing we can think is the head I'm using (off a 34 N1 motor) has a few imperfections in it which is causing turbulence. I'm using a china manifold, but the same type on Natalotto's car did 630hp with a T04Z. Exhaust is fine, intake is free, plenum is stock, cams are pretty big (270x10.8).

Disco, I'm using the GCG T04 rear for the 35. It's a T4 flanged 0.84 housing. I don't think the rear housing is the issue to be honest.

[shanef]

Cerbera's car has been parted out for about a year, so the T04Z run is a little old.

We're stumped as to why it's restricted. The only thing we can think is the head I'm using (off a 34 N1 motor) has a few imperfections in it which is causing turbulence. I'm using a china manifold, but the same type on Natalotto's car did 630hp with a T04Z. Exhaust is fine, intake is free, plenum is stock, cams are pretty big (270x10.8).

Disco, I'm using the GCG T04 rear for the 35. It's a T4 flanged 0.84 housing. I don't think the rear housing is the issue to be honest.

It could well be the head, upwards of 500hp is near capacity for the gt35 so everything would have to be working pretty damn near perfect in conjunction with each other to get everything out of the gt35.

Actually, after comparng ur graph to a mates latest tune graph, i would almost put money on it being the head. Both power lines are near identical until ~106kph where his power picks up extremely fast. His graph is below, his is a built 25 but his head has solid lifters, 1mm exhaust valves, extensive porting and chamber work but only 260/9.15 cams. It's on a pretty safe tune aswell and theres plenty left in it.

[discopotato03]

Some people are doing well with the 1.06 twin scroll T4 International flanged turbine housing , I guess it depends on what your position is with TS .

Also the 82mm compressor is GT40 family and tends to like keeping it in the family with a GT40 back plate and comp housing .

If you look at HKS's comp housing for the T04Z I believe most of them have a larger diameter diffuser wall cast into them . The GT40's diffuser diameter is larger than the T04's and I believe a step in the right direction .

If you can have a look at the GT3582R's compressor map , narrow ranging for an 82mm GT family compressor end . Also from the turbine maps you can see how they scribe an arc rather than rising to a sort of plateau and flat lining .

The more expensive option but a well setup GT4088R is better overall for higher outputs than either a Gt3582R or T04Z .

My 2c only , A .

[Rezlo]

Just for interest sakes, what is the most amount of power one of you guys has got out of a GT35 .82 T3 flange? regardless of motor setup.

[Brockas]

How long is a piece of string?

I made 560rwhp then 510rwhp on two dyno's only a week apart.

If you're chasing figures, a GT35R isn't for you. If you're chasing a great track/street turbo then..... well.... I rate it.

[Rezlo]

How long is a piece of string?

I made 560rwhp then 510rwhp on two dyno's only a week apart.

If you're chasing figures, a GT35R isn't for you. If you're chasing a great track/street turbo then..... well.... I rate it.

I wasnt asking how long a piece of sting is, I was asking which is the longest

The GT35 isnt/wasnt for me, I know that, I ripped it off and went T04z, just wondering what the highest figures are guys pull out of the medium A/R GT35's...

Heard rumours of some very high HP GT35's running around... just wondering what the "norm" power at 30+psi is you guys expect,

[DCIEVE]

WA at least the highest I've heard of is ~600 on a hub dyno but I dont know the specifics of the setup (a/r, boost etc). I'd say I could get there easily with more boost but who knows when the set-up will run out of legs, 'only' 25psi at the moment.

Brockas set-up is as much as 110hp down on mine under 4500, something is amiss there.

Edited August 10, 2009 by DCIEVE

[Rezlo]

Thinking of a GT35 twin scroll for a new project im working on, aim would be 550-580whp so maybe I can squeeze it, T04z would be a touch violent for a 600kg car.

[DCIEVE]

Would be very interesting to see how a twin scroll t4 1.06 a/r rear (as recommended by fr) would perform compared to the garden variety single entry t3/t4 0.8x. FR claimed spool and response would improve, but I wasn't convinced the difference would be great enough to justify the expense considering I'm already making pretty good power by 4000rpm (more than most low mount twin combinations I've seen).

Edited August 10, 2009 by DCIEVE

[discopotato03]

When you want all that the GT35 turbine and the GT40 compressor can give you have to move beyond the housings Garrett fit to the GT3582R .

As a center section the GT25 based BB one is on borrowed time with wheels of this size . Occasionally if leaned on really hard GT3582R's have been known to bend the turbine shaft and the compressor then does a elliptic orbit and trashes itself .

I'm not 100% sure but I think this turbo may have grown out of the HKS spec "GT3240" - which itself had a bored out GT30 based turbine housing and a T04S compressor housing .

Geoff Raicer played about with a few things and came to the conclusion that for these turbos to survive super duty work they need to be built into the larger frame (center section) size with its beefier bearing section and larger diameter shaft . Once the cartridge can survive then you can use housings better suited to the gas flow requirements of 650 + horsepower .

Turbonetic built one with a slightly larger turbine - and shaft - and call it F1-35R , it also used a reasonably beefy twin scroll T4 International flanged turbine housing to make it work .

I think in the end Geoff though why go through all this grief and expense when Garrett already had their GT4088R which is a far more modern thing on all counts .

Garrett went to a lot of trouble with the 78 trim GT40 turbine and housing to make these units responsive for their size .

The compressor may look wuzzy on paper (52 trim) but your talking 52 trim in an 88 mm diameter wheel so not really lacking . The SPEED match is what makes that 88R's wheels complement themselves really well .

If you get the chance go have a look at a GT4088R because they are big on performance but possibly not as physically big as people may think not having picked one up . Nothing like GT42R big .

In my opinion they are more of a 3L engine turbo than a 2.6 one , Geoff did try them on RB26's and to be honest I can't remember how they went - probably as you'd expect a 650-700 Hp turbo on a low compression 2558cc engine .

The T04Z does have its place , its just IMO that HKS put all their smarts into their housings because they knew the Garrett ones were a bit ho hum on a high performance petrol engine .

Cheers A .

I believe just north of 500 is where the "T3" flange runs out of real estate . Maybe a bit less in twin scroll form .