Confirm Stock Turbo R33 Gtr

[Pezhead]

Hey Turbo experts, I need you to confirm this. I bought an R33 GTR from a fellow SAU member in August. I was told that the engine was totally worked over and had N1 turbos. I just had a tune and it didn't make the power it should have. In fact the tuner said the turbo's came on like stock.

I've removed the heat shield but can't see any Serial Tags on the Turbos. Attached are some pictures of the compressor side. I used a magnet against the wheel and it will stick to the shaft/nut but not to the impeller. So that means these are stock ceramics right? And I've been running 1 bar low boost and 1.2 high boost. I'm a bit furious now! But I guess at least I found out before the ceramics let go and ruin my motor.

[EDIT]

I think my may have been too quick to jump. I tested it again but with a multi-meter this time and the wheels conduct so they aren't ceramic. Odd that the magnet didn't stick. They must be some hybrid alloy that's non-ferris like stainless or perhaps titanium.

I'd still like a confirmation just for peace of mind in my assessment.

Thanks for the correction. Do I have egg on my face. Too much to learn.

Edited January 24, 2008 by Pezhead

[N1GTR]

Well if they're stock they wont last long on 18psi

[joe blo]

did you get receipts for the motor? if theres no receipts the works not done is my thinking.

though its not always true coz i put a new motor in my vl turbo and didnt have a receipt to give the dude but it was definately new.

[rev210]

the compressors aren't ceramic mate, even on the stockers. They are made of alloy so no magnet sticks to them.

What you are looking for is ceramic exhaust turbines. Obviously on the exhaust side not the compressor side.

be carefull before going off about it.

[R31Nismoid]

^ As above. Pretty excited post over nothing far as i see it

You really need to know what your looking at... its meant to be the exhaust side dude.

Check the exhaust side, then let us know.

Alternatively check the ID plate on the turbos

[VSPEC-33]

The ceramic wheel on the turbine is on the exhaust side, so dumps would need to come off to truly see what you have if theres no serial numbers.

As to why the magnet doesnt stick to the intake blades, could it be inconel (or whatever its called, special alloy) maybe a magnet doesnt stick to it?

With a A/R42 front housing it could still be garrett -7 N1's.......

[Pezhead]

Thanks for the quick reply fellas.

I've amended my earlier post. I'm still trying to figure out why the car is low on power. I guess I was a bit hot too from working two hours just to get the exhaust shield off but still can't see the turbo serial no's. No excuse for me.

Should I check the exhaust sides too? I'm reassured by the shop that did the work that they are N1's with reworked stock housings. Since the original owner ran high boost all the time I guess these must be at least steel or they'd blown by now.

I did get the original receipts but they don't list the actual parts since some were bought second hand. The original worked motor was purchased and freshened before it went into my car. Don't have the original parts receipts.

Maybe I'm just paranoid, the car does have most of the other goodies listed, but a few are missing - oil cooler and alum radiator that were originally on the ad.

Edited January 24, 2008 by Pezhead

[Duncan]

I've seen Seb's car around previously including at Eastern Creek track days, and it was definately making good power on big turbos. Of course thats no guarantee that something hasn't ben changed but it used to go great.

What power did it make, and at what boost. What were the compression test results. What is the cam timing set to assuming it is adjustable? Does it have upgraded cams?

[Beer Baron]

.42 AR compressor housing is stock size. my stab is that they are stock turbos, or perhaps rebuilt stock turbos. check the rear housing and look for A/R. it should be 0.64 if it is then they are something decent.

[Pezhead]

Thanks Fellas. Sorry for the panic earlier, I read a few posts where people were suggesting the Magnet check and turns out it doesn't work at all. I'm a bit tired from working in the hot garage - what a sweat box!

I can't really get to see the rears unless I unbolt the dump pipes and a lot more stuff so going to wait for an exhaust upgrade or something before I do that.

I did check the cam gears and they are HKS adjustable. Intake is set to 7 degrees advance, 0 advance on exhaust. I wanted to check the cams too but thought I'd check the lift through the oil filler before I take off the valve cover. I used my digital calipers to measure the distance from the bottom of the oil filler seat to the cam lobe. Lift looks like about 9.8 mm but could be off since my crude method of measurement.

Don't get me wrong. The car makes great power and drives terrific. I'm trying to go through everything now and ensure that the machine is in tip top shape and do the mods necessary to ensure the longevity of the motor and parts.

1) add 19 row oil cooler since it doesn't have one at all and oil hits 90 degrees just doing street driving

2) big radiator upgrade - the M-spec Alum version from here

3) gotta do something about intake temps. temp is 50-60 degrees off boost on a 20-25 degree day. Engine bay is very hot and pods are pulling in the hot air. Want to enclose the pods, but they are bigger than normal and will require a lot of custom box building.

4) cat has split open due to road rash (is the lowest part of the car)

5) new Trust/Greddy suspension on the way (but back ordered darn!) to get the car back up in height to solve cat prob and even out camber on the front wheels

6) Oil pressure and water temp gauges so I can keep a better eye on things

I think the tune I bought it with was a bit off. UAS was able to significantly increase the power without sacrifice to mid-range. It was only making 180 rwkw @ 18 psi when I drove it in and now at 253 rwkw @ 17 psi (interesting 1 psi drop from original tune). Even they say their dyno reads a bit low compared to others. Seb said the car made 320 kw @ 21 psi. I originally thought the high boost was set there but it is not.

By the way. Low boost @ 1 bar is fully in before 4000 rpm and high boost 17/18 psi all in before 4400 rpm. Does that sound 'bout right for N1's?

Trying to make sure I'm confident in everything before I try turning up any more boost. I've had sports cars before but nothing like the GTR (which is why I had to have one). I knew buying a modified car would force me to climb the steep learning curve on import tuner's.

Thanks again for your help guys. I'm up for the challenge.

[ali-turko]

well stockies usally come on boost earlier, what model n1s are they suppose to be? and what else has your car got?

[Pezhead]

Its got a big trust imitation intercooler, 550 cc Nismo injectors, Autronic SM2, HKS EVC and 044 pump with rising rate reg & surge tank. Tuners said that the fuel system works great and held constant 12:1 at full boost (raising from 14:1 at low end).

I'm a bit stumped because the tuners thought the turbos should come in earlier too.

I'm also getting terrible mileage too. Car was getting about 250k's per fill (filled at 1/4 tank) and now is only marginally better at about 280. I've read up and most folks are getting a lot more with same or more power.

Could this be an exhaust restriction?

Thanks.

[ali-turko]

you may have a vaccum leak, split intercooler hose or something, my car got robbed by atleast 50kw and got me bout 200km per tank when i had a split cooler hose,

its just a suggestion