rb20det turbo

[craftz]

I checked up on the turbo guide for our cars and it states it is a ball bearing turbo. Would anyone be able to verify this, like having one apart and seeing if it was ball bearing or journal? I talked to Herman at Cherry Turbos and he told me he cannot upgrade it if ball bearing. I don't want to take it out for nothing.
Thanks

[RixR32]

OEM RB20 Turbo is NOT ball bearing. Journal with ceramic exhaust wheel.
Not sure on the specs of rebuilt/upgraded OEM Turbo, but getting the steel exhaust wheel is an important part.
I know Skym knows the specifics of the ugrade.
Cherry Turbos is good too, sometimes they take a while but it's done right.
I had an old MX6 IHI Turbo done out there and was very impressed.

Rick

[Skym]

Stock RB20DET turbo is ballbearing. R32 GTR stock turbo's are 270 degree journal bearing.

Rebuilt RB20 turbo is known as a hybrid turbo, as uses stock compressor, stock exhaust housings with Garrett CHRA, wheels.

Stock RB20 turbo specs -

42x59 compressor wheel
.50 A/R compressor housing
51x43 exhaust wheel
.4 A/R exhaust housing
Rated to 250hp

Hybrid RB20 turbo specs -

Garrett TB03 CHRA
72 trim T3 shaft
46.5x60 compressor wheel (60 trim T3 compressor wheel)
58.9x48.7 exhaust wheel
Machined stock RB20 turbo compressor, exhaust housings to suit bigger wheels

You can extract up to 295rwhp-308rwhp with hybrid stock RB20 turbo on stock RB20DET engine with basic boost up mods.

Basic boost up mods -

Stock ECU retune with Nistune
Boost controller
Z32 AFM + Z32AFM plug / tail
Full 3" exhaust from turbo
Deatchworks 550cc injectors
Nismo 255lph fuelpump
FMIC
BOV
Tomei 1.2mm, 80.5mm bore metal headgasket
ARP headstuds
Nissan repair gasket kit
Extra's like machining / skimming head, exhaust studs, etc.

Add drop in Tomei Poncams, ECU retune to suit, can extract an extra 24rwhp at same boost level. So 319rwhp-332rwhp is possible with hybrid RB20 turbo. Or roughly up to 396hp at engine. With adjustable camgears, could extract over 400hp at engine.

If wanted more hp, mid mount RB20 / RB25 exhaust manifold upgrade from HPI in Japan -

http://www.hpi.co.jp/products.html?cate=1&item=1

Specs, price of mid mount RB20 / RB25 exhaust manifold -

http://www.hpi.co.jp/products_zoom.html?cate=1&item=1&zoom=1&format=1

[canadianjoker]

Skym, you are the man!

this looks like what was done to my turbo, i was told it was rebuilt, but i couldnt get any solid info from the person i bought it from. (all i was told is, it was rebuild with a steel exhaust wheel, and the shaft was changed.)

would this rebuild change the sound of the turbo(mine has a whine almost like a supercharge, yet its been running strong for 2+ years) and what would be the max boost you could pull out of said "Hybrid" turbo.

Josh.

[craftz]

Thanks for the replies. I will call Cherry Turbos again, give him Skym's specs and see what he says.

[Skym]

I noticed some run 16psi+ through the hybrid turbo's on RB20DET. Wouldn't run above 12psi with stock injectors. If turbo is balanced, built properly so it doesn't chew the oil seals, shouldn't fail. Whistle sound can be airleak after turbo (especially on the intake hose joiner that connects to J pipe from intercooler intake piping) or compressor wheel touching compressor housing. Pulling rubber intake hose off front of turbo and checking compressor wheel play (excessive play, as there can be very minimal play which is supposedly normal) should tell you straight away if there's a problem. Excessive play means compressor wheel can touch compressor housing or just be very loose.

As far as I know stock RB20 turbo is made for Nissan by Garrett Japan. I found out from reasearch that a TB03 CHRA is the same CHRA as used on old school stock VG30DET turbo. Later model VG30DET are ballbearing.

[RixR32]

Wow, I always thought OEM RB20 turbo was NOT ball bearing center section.

I'm an ass I guess

[nelsonmxmarc]

They're quite underrated turbos.. I've been pushing mine a little over a year now running 14.7 lbs.. Later in the past year it saw a daily driven boost of 16 lbs without an issue. Like someone mentioned, its entirely in the balancing. The only downfall to the rb20 turbos is their ceramic exhaust wheel.. So far, only my uprated rb25 has seen exhaust wheel failure, my rb20 has not.

Another question to pose is the issue of oil restrictors in the event of swapping a journal bearing turbo to a ball bearing turbo. Many people stress over the issue of whether or not one is necessary. So if what you're saying is true, and rb20 turbos are BB as opposed to JB (or jail bait..........) an oil restrictor is not necessary when upgrading turbos? interesting..

Just out of curiosity and since we're on the discussion of turbo's, refresh my memory if the S1 S2 rb25's were journal? I believe only the NEO "garrett" stamped RB25 out of the R34 GTT's were BB.. Then in that case, people would need to change feed lines to accompany more oil capacity as journal bearings feed off high oil capacity..

[craftz]

We'll, I just got a response from gpop turbos and they say that nothing can be done to my turbo. I am still waiting for a response from cherry after I sent them Skym's info ( thanks Skym). It loks like I will be looking for another turbo.

[drader]

Sorry for bringing up an old thread but it caught my interest. Skym mentioned use of a "early vg30det turbo". I would just like clarification. Did you mean vg30et? Or vg30dett? Or did you actually mean vg30det, because those are quite a rare setup to find. I had a vg30det on my nissan Gloria and no one had ever heard or seen a single turbo vg30de before.

[Skym]

VG30ET turbo (F31 Leopard???). I always think it's a VG30DET turbo due to some use later model version of that turbo, which are said to have a ballbearing CHRA and as far as I know is found on VG30DET in Nissan Gloria's, etc.

[spinnanz]

I have seen many rb20det, 25det and 25det neo turbos, (ex skyline, stagea, laurel and cefiro) NONE were ball bearing.

[Skym]

Interesting. Were they hybrid stock turbo's????

Had to drill the stock RB20DET turbo oil feed when fitting a hybrid RB20 turbo that's non ballbearing (requested to do so by turbo rebuilder).

From what I understand -

Ball bearing CHRA = smaller restrictor

Non ballbearing CHRA = bigger restrictor

Also from what I understand, bigger turbo might need a change in restrictor size, as the oil gallery size inside turbo might be bigger.

[spinnanz]

yeah all were stock, fresh off the boat engines from Japan. Correct that BB use a smaller restricter, as they require less oil

[mattheripper]

Do you happen to know the AR's of the vg30et turbo, Skym?