Journal Bearing Single Turbo And Rb26....

[002-M-P]

I posted this over at gtr.co.uk, but haven't got any responses really, maybe you guys can help me out...

I have been searching for info on this for a while now. I would truly like to buy a GT4088R and be done with it, but right now money is tight and I'm not sure I can afford a ball bearing turbo when the time comes.

So what I am looking for is anyone's input on spool time for decently sized journal bearing turbos on a stock displacement motor with stock heads. My goals are between 550-600 whp. I have a pretty good knowledge of turbos and choosing the right turbo, but some first hand RB26 specific info would be great. Specifically these are the turbos that I am looking at mostly...but if anyone has any other suggestions definitely don't hesitate to voice you're opinion. Some specs were hard to find.

Also I must state, that this will be in a LHD Z33 and I really do not want to deal with the hassle of twin turbos and downpipe routing around the steering shaft, so twins are pretty much out. My hp goals are in the 550-600 whp on pump gas. The motor has CP pistons and stock rods with arp rod bolts...fyi.

Garrett TO4R

compressor: TO4S

.70 a/r

66.5mm inducer

84 trim

flow: 75 lbs/min 960cfm

360* thrust bearing standard

turbine: T4

.96a/r divided

P trim wheel

flow: 75 lbs/min 960cfm

360* thrust bearing

wet center section

Garret GT4088

compressor

.72 A/R

88mm 54 trim

turbine: T4

1.06 A/R Divided

77mm 84 trim

PT66

Compressor:

66mm inducer

52 trim

Turbine: T4

.96 A/R Divided

P-Trim Wheel

76 Trim

360* Race bearing

[Slide]

We reparied and highflowed a HKS T04S on a Tommy Kiara R33 GTR

All the important bits putting out 685rwhp hitting 1.5 bar at just after 5000rpm.

This is with HKS 272 degree inlet and exhast cam shafts on a near standard displacement engine (2.645) 87mm pistons built at Signal in Japan.

Most big horsepower singles are Journal

[discopotato03]

I would have thought a ball bearing TO4Z would not be the end of the world these days depending where you got it from . If you know someone who can strip BB turbos a cheap way to build a TO4Z is to buy a Garrett T3/T4R , one of them is a TO4 P trim/60-1 hybrid (cartridge or CHRA no 757179-0001) and that compressor can be flicked for the TO4R compressor that TO4Z turbos use . Some machine work is required because often bush bearing compressors use different back spacing to ball bearing ones .

HKS's TO4R is just the same P trim turbine /TO4R compressor with a slightly cropped turbine in bush bearings .

The part nos for the wheel , housing and backplate are 451470-0001 , 409722-0023 , and 408997-0018 in bush bearing TO4S outline form - according to my data . It shows the wheel as BCI-8D family .

Cheers A .

[002-M-P]

So any other experiences with spoolup time and journal bearing turbo's like these?

discopotato: Is that to make a T3 based TO4Z?...because my manifold will be T4 divided.

Edited January 24, 2007 by 002-M-P

[StockyMcStock]

plain journal GT4088 1.34 rear housing on my stock headed 25/30 was on full boost around 4500 in 2nd gear, earlier in higher gears. they're a good thing i reckon with a smaller exhaust housing than mine. they have a HUGE compressor cover so watch your clearance to the strut tower etc. TA45 split pulse flange on em i believe.

[discopotato03]

TO4Z's are really easy with turbine housings , ANY TO4 P trim turbine housing bolts up to them in a myriad of A/R sizes , and single/split T3 flange or single/split T4 flange or single/split TA45 flange which is sometimes called T4 International . The only thing to watch using Diesel spec turbine housings is that they sometimes develop cracks over time because the material spec was intended for the Diesel engines lower exhaust gas temperatures .

Garretts GT40 range of bush bearing turbos are more modern designs than their TO4S and TA 45 ranges . Better cartridge and wheel technology though not right up with the BB GT4088R . This ones a ball tearer depending on the airflow required and even has the high temp spec turbine and housings for petrol performance apps . The down side is a retail price of someting like $2750 . With our rising dollar and sales competition it may get better .

Cheers A .

[002-M-P]

Thanks again disco....any chances that the GT4088R bb center section is compatable with the GT4088 journal bearing turbo's housings? (That would be a nice stepup program for me)