R33 Gtr - Stock Turbo Limit For Track Use

[tommis85]

Hi all, I seem to have stumbled across an oldish thread where a heated duscussion raged on what caused stock ceramic wheels to fail. I recommend this thread:

http://www.skylinesaustralia.com/forums/Ce....html&st=60

I posted a couple questions at the end of the thread but I don't think many people frequent this one much anymore so I thought I'd re-post my question here.

What is the limit of stock 1995 GTR turbos when using them on the track? In one of my recent posts I was assured that taking out the boost restrictor was perfectly fine....

BUT....is this safe for track use? I have been advised on the above thread that it's suicide.

Could someone who's in the same boat please help me out here, because if it is unsafe then I will put my boost restrictor back in for the next track day (to bring it down from 14 pounds to 11 pounds approx)

I'm under the impression that 14 pounds / 1 Bar(ish) is OK for a squirt every now and then but is very dangerous for 5 "hot laps" on Queensland Raceway lol

Any experiences would be much appreciated.

Cheers

Tom

[ferni]

It's not black and white, its grey.

I ran 1bar on stock turbos/engine at the track with no problems. So have a lot of other people. But of course 11psi would be safer than 14psi...

[tommis85]

What's not black and white lol? I'm lost....did I mention that somewhere lol?

Well, I went for a quick squirt after getting exhaust and pulling restrictor out and I too still have my turbos in there. See this is where it gets difficult, when you have people who apply the 1 Bar rule-of-thumb without any problems and love it and then also get people who say it's "suicide"....just quoting from the linked thread above.

I guess it depends on how you drive too. If you drove up a continuous incline, in 4th on max boost (14 pounds)....then well, the answer is obvious.

...but Queensland raceway, it's a series of corners and hairpins with only really the front straight when you can open up them throttle bodies

I have to have a look but I dont think I'm running exactly 14 pounds....I think it's a tad over 13. Maybe I should put my controller in and wind it down to 12 or something for track use - that's still a good level.

Do you now run upgraded turbos? Or are you still on your stockies?

I've been checking out GT2560's, 2860, GT-SS and GT-RS's....lots and lots of reading lol

[djr81]

I ran an older GT-R (A 32) at the track over a number of years on 13#. There is no reason why you should have problems at this level as it is relatively safe. It is however always possible. There is no hard an fast rule, but there appears to be a consensus that 14# is a perfectly acceptable number for these turbos.

Be sure that the engine is warm before you go out on the track & give the thing plenty of time to cool down after each run.

Also be aware that wear and tear will be relatively high on your car mostly the brakes and tyres. Keep an eye on your oil temps too.

[tommis85]

djr81,

Yes that's very true with the brakes and tyres. Yep, the oil temp crept up a fair way on my GTR which makes me want to get a proper cooler for it. Yup, I drive for a good 45mins or so to get to the event so there's some good heat going into that engine on the way. Sometimes it's too tempting to keep going - but normally I try to use the cool-off "in lap" for what's it there for lol and then, in the pits I let it idle for ages with the bonnet popped.

I do sat-arvo sprints and also want to get into top gear sprints....so, because they're just sprints there's no reason why you cant take it easy on the first lap if one's that concerned about the motor ;-)

Well, at the momment there are more people voting for 14 pounds rather than against. A bar is 14.9 or 14.6 pounds anyway so I'm not even on a bar yet.

Tom

[djr81]

Try and organise yourself so you can fully utilise the three flying laps you are given. Don't chuck away a third of the days running because of something you are missing in your set up.

[tommis85]

That's very true mate. Should get the car all decked out...at least turbo wise so I can run a proper 14 pounds like most turbo cars do with stock engines (WRX's, Cordias....anything wtih Vr4's in them etc)

I just got a quote from one of the turbo specialists in town and they're around $1200 each for a pair of T28's. (I believe these would be a version of the bolt on T2860's) So that's not too bad of a price but I better comfirm it on the Garrett site.

What do you run in your's if I may ask???

T25's,T28's, GT-SS's, GT-RS's and N1's seem to be a common upgrade...???

[ferni]

I run GTSS now.

Get an oil cooler - heat is what will kill the stock turbos, keep the temps down.

If i were to buy a stock GTR (or GTR with stock turbos) I'd take out the restricter and run 14psi on the track, but that's just me. Others may prefer not to. But you always have to be prepared for things to break on the track, your driving it harder than you will ever be able to on the street.

I'd get it tuned as well before going out on the track.

[tommis85]

A GT-SS is a GT2860r-7 correct?

I'm looking into those at the momment - they appear to be a pretty good upgrade with stock cams etc - actually, they're meant to go well with the cams.

Yes I did notice the oil temp creep up last time which alarmed me...it went about 1/3 up the gauge. But then it is driven exceptionally hard!

These may be silly questions, but what sort of things should the tuner be checking for? AFM's, fuel pressure, timing, O2 sensors, spark/coil packs...I have been lead to believe that the GTR's ecu can overcome some tuning problems on it's own....but that may be just a heap of sh]t???

Thanks for the help Ferni

[ferni]

Not sure if the -7's are GTSS equiv - i always get confused, I thought they were the -10's that were the same as GTSS.....?

They are good for around 300rwkw safe, or pushing towards 350rwkw if you really get on them. Good turbo choice for a stock engine...

Get a nismo centre cluster gauge so you can tell the oil temp rather than guessing with the stock one - or a real oil temp gauge if you like. You want to keep oil under 120deg. If get gets over 120-125 you should be backing off to let it cool. But defiantly get a good oil cooler setup.

As for a tuner - Yeah pretty much what you listed, i dunno i just pay the money and drive my car I think with a stock ecu and stock turbos, they up the boost to about 1bar, put in a fuel pressure reg to lean it out a little, and tune it that way. You could look at getting a powerFC, they work well with the standard setup as well.

[djr81]

That's very true mate. Should get the car all decked out...at least turbo wise so I can run a proper 14 pounds like most turbo cars do with stock engines (WRX's, Cordias....anything wtih Vr4's in them etc)

I just got a quote from one of the turbo specialists in town and they're around $1200 each for a pair of T28's. (I believe these would be a version of the bolt on T2860's) So that's not too bad of a price but I better comfirm it on the Garrett site.

What do you run in your's if I may ask???

T25's,T28's, GT-SS's, GT-RS's and N1's seem to be a common upgrade...???

If you are not going to push the motor too hard then the smaller of the Garretts (GT2860 707160-7) or the HKS GTSS are a very good turbo.

Equally some people are happy with the HKS 25-30 or the Garret GT 2860 707160-5 which is basically a size up.

Personally with the prices of turbos these days I would much bother with old N1's or similar.

If you search the site you will find out what mods (eg AFM's, ECU, injectors, pumps etc) are needed to go with a given amount of rwhp.

[tommis85]

djr81,

I just want some nice decent power - around 300rwhp or so for track use (sprints etc - not drag).

I've been in contact with my mechanic and he has recommended a pair of GT2560's which are meant to be the N1 equivalent (according to him) I thought the GT2860r-7 is N1 equivalent (for the R34 GTR)

I just gotta remember that these bigger T28 turbos are only fed by 1.3L lol!!!! There would be jack all low end power...the GTR would become one of them lag monsters! I've been told that the 2860's make awesome power on SR20's.....you sure they're not too laggy on only 1.3L input?

....or?

Yeh, I'll have a look at the other threads - are some really good ones on here. I want to look up single turbo conversions too.

Cheers,

Tom

[djr81]

djr81,

I just want some nice decent power - around 300rwhp or so for track use (sprints etc - not drag).

I've been in contact with my mechanic and he has recommended a pair of GT2560's which are meant to be the N1 equivalent (according to him) I thought the GT2860r-7 is N1 equivalent (for the R34 GTR)

I just gotta remember that these bigger T28 turbos are only fed by 1.3L lol!!!! There would be jack all low end power...the GTR would become one of them lag monsters! I've been told that the 2860's make awesome power on SR20's.....you sure they're not too laggy on only 1.3L input?

....or?

Yeh, I'll have a look at the other threads - are some really good ones on here. I want to look up single turbo conversions too.

Cheers,

Tom

If you only want 300rwhp then you don't need to change the turbos. The stockers will run safely at this power level.

For a time the 2860 was known as then 2560. The core was even tagged as such. Mine are. So your mechanic is probably referring to the exact same turbo - or he should be. Check the Garrett site but the item is, irrefutably a GT2860 707160-7. Make sure what your mechanic is talking about has the correct flanges etc as some of the old Garrett options did not bolt up directly.

The are a number of different sizes/types of 2860. So yeah one or other of them probably suits an SR.

Check the other threads you will find the GT28-60 707160-7 does not have lag issues.

[tommis85]

Thanks mate - ok, I'll have a look. Thanks for your help. Are you sure that the stockers make that much?

If the GTR makes approx 220hp at the rear on stock boost which for me was around 11 pounds....then, how much would it make at 13.5 pounds you reckon? 260-270hp??? It has 3" system to help with flow (and also hi flow intake.)

Also, if I went for the upgrade turbos you mentioned above....what sort of power could I expect from them? I think I may have under-estimated them by the sounds of things? Would I be running these upgraded units on around 15 pounds as my entire engine bay and support system is stock (ie, pump, injectors, regulator, coil packs....the works)

[ferni]

Stock turbos,1bar of boost cam gears and a quick tune, you should be getting about 250rwkw, which is about 330rwhp

If you go for GTSS equiv turbos, on a stock engine, stock inj/pump etc... 300rwkw is about as much as i'd put into it which is about 400rwhp

[tommis85]

Andrew, I just got a questions for your last post there...

You say a "quick tune".....what should my mechanic look out for? AFM's, timing, injectors, spark....O2 sensor readings???

I know that after so many years the GTR definitely needs to be tuned...it's just that people have told me that the GTR can look after some of the tuning by iteself???