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

[Lithium]

"GT3566" sounds like its moving closer in the direction of a T04Z than a GT3582R. One of my mates made 1bar by ~3500rpm with a GT3582R and a 6boost manifold on an RB25 so 20psi by under 4000rpm with a cammed RB26 and a good manifold could be conceiveable. The 4300rpm 20psi 370wkw setup was with a first ever effort manifold made in the garage and probably gives a fair bit away to things like 6boost/Fullrace manifolds.

[Rezlo]

For those that love to hate.

T04z on RB25 with small cams planted in a S14...

1bar by 4000rpm

1.5bar by 4300rpm

2bar by 4500rpm

Done in 4th gear because I cant hold the video cam and drive in 3rd as the 285's loose traction (got some vid of that as well)

If you want to see the video supply an email addy as its 19mb because as soon as i compress it you cant see the rev counter...

Edited December 31, 2008 by Rezlo

[tommis85]

For those that love to hate.

T04z on RB25 with small cams planted in a S14...

1bar by 4000rpm

1.5bar by 4300rpm

2bar by 4500rpm

Done in 4th gear because I cant hold the video cam and drive in 3rd as the 285's loose traction (got some vid of that as well)

If you want to see the video supply an email addy as its 19mb because as soon as i compress it you cant see the rev counter...

Rezlo,

I wouldn't mind checking the video out as I too am tossing up between a T04z and a GT35. Maybe you could post it up on youtube? My email is [email protected]

Cheers,

Tom

EDIT: yep, I'm hating already! LOL

Edited December 31, 2008 by tommis85

[Rezlo]

Sent,

Both vids are with a full 3" exhaust as well (they very serious about sound emissions here) when I run the 4" dump from the down pipe for drags it spools up a bit faster.

[Roy]

Rather then looking at what boost it has at 4,000rpm, can i ask how much torque and power it is making at 4,000rpm?

[Rezlo]

Unfortunatly I can not tell you that, we only have one proper hub dyno in RSA, thats about 1400km from where I live, all our local home brew dyno's love to have cars walk at anything over 300kw so we learn to do without dyno's for tuning or power runs.

First round of our nationals are in feb, will see if I can get it on the hub dyno,

Edited January 1, 2009 by Rezlo

[daineisdabomb]

i have a fully built rb25 with a GT35 with .82 rear housing. it hits 20psi at 4000rpm, which is great for the track but i drive the car on the street more and find it a little laggy on the street. im goin to change the rear housing to a .62 as i feel i would enjoy driving it more and its not all about how much power it makes its about how it makes the power n wen. dont get me wrong it is reasonably responsive n 4000rpm for 20psi is good but u need the rev the crap out of it all the time to hav the power n u just cant do that on the street unless u want to loose ur licence. but hey like i said wen ur on the track and the revs are up round the 4000k plus the turbo spools very quick n is awsome.

[discopotato03]

Well OT but IMO you could have made more than enough power with a GT3076R which for its size is a better thing than a GT3582R in small turbine housing form . 2WD RB25 , how much can you get to the ground .

My opinions only , cheers A .

BTW has anyone looked into the large frame BB P/60-1 ?

http://www.atpturbo.com/Merchant2/merchant...tegory_Code=GTB

http://www.atpturbo.com/Merchant2/merchant...tegory_Code=GTB

Cheers A .

Edited January 2, 2009 by discopotato03

[T04GTR]

ive drivven both round a track. the 35 is more lazy and comes on sooner but much less urgantly. it drops right of on gearchanges

t04z has to be driven in anger comes on much harder but makes more power. it is much laggier on the track but. it doesnt drop of nearly as much as on gearchanges once its going.

unless you are a gun driver (which im not) the 35r will be a better choice. but you will miss the exitement and power of a t04z.

you really need to work out if you can live with lag. 350-400kw is a very broad and dificult target to reach with minimul lag.

[Lithium]

t04z has to be driven in anger comes on much harder but makes more power. it is much laggier on the track but. it doesnt drop of nearly as much as on gearchanges once its going.

You mentioned this dropping off on gearchanges thing, thats a bit weird - was it more than one car that you have experienced this dropping off thing with GT35Rs? I've been in cars running .63 and .82 GT35Rs on RB25/26/30s and once you are in the "happy zone" they have always come on nice and hard and certainly no falling over in gears - wonder if what you have experienced there is something a bit different.

[Rezlo]

Maybe it had the new HKS BOV? of the 3 Ive now used on turbo's bigger than GT30's with 1.5bar or more they all dont shut fast enough making the vehicle feel terrible between shifts

Edited January 2, 2009 by Rezlo

[leg46y]

What would the other determining factors (other than the turbo) as to where/how quick your car builds boost/power?

Eg; if two cars using identical turbos (incl rear housing), what would be the major things that differntiate their power outputs?

eg

-maifold design

-cams

-exhaust size

because i guess you could get a properly set up T04Z making power nearly as early as a poorly set up GT35 Right?

sorry if this doesnt make sense, im just trying to understand the 'bigger picture'

[T04GTR]

to me it felt like the inertia of the t4 kept it spinning longer than the 35r inbetween changes. both cars had a properly functioning bov vented to atmo (ie no flutter)

[Rezlo]

Yes I agree with you, if I change over 5000rpm that power is there almost instantly in the following gear...

the T04Z/T67BB/whatever people call them are "So pre-2005" these days haha.

Makes me wonder how the GT35 is so much more advanced for having so much less power and only fractionaly faster spool up.. Maybe Garrett is working backwards?

[Lithium]

Makes me wonder how the GT35 is so much more advanced for having so much less power and only fractionaly faster spool up.. Maybe Garrett is working backwards?

Because while the GT35R has a lower power potential makes a reasonable amount less power, it is MUCH better in terms of spool. Here is a dyno comparison of a GT35R and a T04Z on very very similar engine setups and boost levels:

You can see the GT35R is starting to fall over though the T04Z setup with 270deg cams might have a bit of a breathing advantage as there is no other rational explanation for it to be making more power through the midrange on less boost.

[DCIEVE]

I'm fairly sure thats my 35r in the plot above. Here is the original which explains the strange power curve. The mid-range is weak as its only 1.3bar, boost creeps as revs rise as does power. The drop-off up top is due to boost coming back down to where it should be.

My head is stock with only tomei poncams whereas Simons gtr (I'm fairly sure thats his in the plot) has some headwork/cams. Looks like Paul has scaled my plot to account for the difference between hubbers and dd.

Edited January 6, 2009 by DCIEVE

[Lithium]

If he has scaled it, it looks like he has given the T04Z the benefit of the doubt as really with the amount of boost the GT35R is creeping up to in the midrange I'd expect it to surpass the T04Z at those rev ranges, though the T04Z will no doubt edge it out before and after those points.... shame about the "funny" boost curve as it doesn't do the GT35Rs strengths over the T04Z justice, even in shape of the curve. Its still pretty blatent how much better it spools, though.

[bubba]

If that graph is of Simons' GTR then that's not really a typical example of a T04Z on a typical RB26.. it's all horses for courses though!

[Lithium]

If that graph is of Simons' GTR then that's not really a typical example of a T04Z on a typical RB26.. it's all horses for courses though!

Simon who? Its some SAU member's one, can't remember his username. There is a Simon in NZ who has a Stagea with a T04Z on it which is also much laggier/weaker down low than any dyno plot I've ever seen for a GT35R - but it makes good power, of course.

The overlay above is the only decent reference of one in comparison with a GT3582R though - do you think its better or worse than usual?? Its consistant with what I've seen overall - all things being equal, the GT35R is invariably a fair bit better spooling than a T04Z and the T04Z is capable of more up top. Its not too surprising, as the T04Z is like 6mm larger on the inducer, bigger turbine, and older design - I'm not sure what magic people think they have which would make them spool similar to a GT35R.

Hell my mate who has a GT35R on his GTR can launch the thing at the drags at 5500-6000rpm without bogging, if it launches the way guys with low mount twins like GT2530s need to he just fries the tyres through 1st - and T04Zs are laggier again than those. Go figure.

Edited January 7, 2009 by Lithium

[bubba]

Simon aka R32-GTS is who DCIEVE is talking about (I think ). Too much headwork to compare to any old 26 with a T04Z