Silvia Club of NSW

Just wondering if anyone here knew if the S15 turbos have got a steel wheel on the exhaust side?


Thank YA!

yep, all the genuine Garrett turbos (T25, T25G, T28) have steel wheels.
The ceramic ones were a Nissan / Garrett development, and they're branded Nissan, or Nissan Motor.

Here's an RB20 turbo: http://www.zgeek.com/albums/album11/RB20turbocomp.jpg

And here's an RB25 turbo: http://www.zgeek.com/albums/album11/RB25_compressor.jpg

The turbine from the RB20 one looks like this: http://www.zgeek.com/albums/album11/RB20turboturbine.jpg

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The Engine Whisperer - fixer of things

Dumhed is pretty correct. Lucky guess

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Disclaimer: I actually DO know everything

Sil80 - SR20DET 231rwkw
Silvia Race Nugget - SR20DET 225rwkw
Stagea - DeathWagon - RB25DET 185rwkw.

My Lame Gallery: http://www.toomuchboost.com/gallery/main.php

but my rb25 turbo has a steel wheel?????

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meh

also....are the jdm BB? and the aus ones non bb?
i read that somewhere at ns.com

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got 15?

Thats what I believe from what I have read up on, alothough its not 100% anywhere

The way I see it if you want a T28BB then get a jap spec one and you'll know its BB for sure.

I think that is still highly debated.

Either way to be 100% sure buy one from Japan.

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S13 Silvia Tuning - The Definitive SR20 Modifying Site

thanks fellas! Highly appreciated!

*smack!*

Actually, my RB25 turbo apparently has a steel wheel too, but I'm not sure how to tell exactly. It was definitely new, and looks steel (ie, not like the RB20 turbine) but it also looks a lot like other ceramic wheels.

It doesn't conduct electricity, but either do a couple of other turbine wheels I have which are steel. They must get some sort of oxide coating that's an insulator.

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The Engine Whisperer - fixer of things

Heheh wind her up to 18psi and see if you find it the cat!

Hmmm that brings me to my other question! What makes a steel wheel handle more boost than a ceramic? Doesnt the ceramic wheel just come off as a whole as the glue or whatever holds the wheel there just let go? So then wouldnt this be the same with whatever is holding the steel wheel on?!

The problem with the domestic ceramic wheel turbo is the bonding process between the shaft and the wheel.

With a steel wheel turbo, the usual process of bonding the exhaust wheel to the shaft is called 'friction welding' which works by holding the wheel stationary, and spinning the shaft into it at ridiculous rpm intil they 'weld' themselves together. This technique has proven to work extremely well as I personally haven't ever heard of a steel wheel dislodging from a shaft.

The problem with ceramic wheels is that you cant weld ceramic to steel, so a bonding agent (glue) must be used. These bonding agents are designed for a given maximum load, and when you go winding up the boost, you generally exceed the load that the bond is designed to take. Also the bond no doubt deteriorates over time.

Another problem with ceramic wheels is that they are extremely fragile. It only takes a little bit of crap through the exhaust ports to chip them, whereas a steel wheel would mulch any foreign object up real nicely with no damage to the wheel

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Disclaimer: I actually DO know everything

Sil80 - SR20DET 231rwkw
Silvia Race Nugget - SR20DET 225rwkw
Stagea - DeathWagon - RB25DET 185rwkw.

My Lame Gallery: http://www.toomuchboost.com/gallery/main.php

damn... good explanation!

I think a rename of this topic would be good for any1 doing a search!

A guy at work has interesting way of testing for ceramic wheels.
Use a 24volt battery (I rekon 12 would do) two leads one with a 10amp fuse and touch them onto the wheel. If the fuse blows its gotta be steel never seen it done till today would have been funny if he fried himself He rekons it works on coated wheels too. Problem with a mulitimeter is the current flow is too small to create continuity through the coating.

yeah I was thinking that might work.
My multimeter actually uses a lower voltage than most too, which could cause a problem.

Might have to do some more testing
Pity I gave *someone* the T25G I had

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The Engine Whisperer - fixer of things

He he. There is something not normal bout that turbo but I cant put my finger on it. I flow tested it yesterday with the engine recon place down the road to make sure it is okay. It out done a T3/T4 that was built for a VL even with the shaft play. sound normal to you?
I measured my meter today(i was bored stiff at work) it only has a 9 volt output with .5 amps