Rb25/vg30 Hi-flow Turbo: Results/comparison

[Al]

Recently there have been a couple of threads discussing the adaptation of a VG30 exh. housing to a hi-flowed rb25 turbo. I have completed such an upgrade and would like to compare my results with others. I am more interested in the response of your setup for this type of turbo, but power comparisons (all though limited) are also appreciated.

So please copy the fields below, past them in a post and edit as required:

(NOTE: Required support mods/systems are assumed to be fitted to the car.)

ENGINE: RB25det, R33 S1

- Std. plenum

- Tomei Poncams (256 Duration, 8.5mm Lift)

- Head "race" ported

- Std. exhaust manifold, but has been ported/hi-flowed

- IN (VVT still active) and EX cam gears. IN set to 0deg, EX set to -2deg

- STANDARD BOTTOM END

ECU: Wolf 3D Ver4+

Exhaust: 3" with cat, long "hotdog" and hi-flow muffler.

RESULTS: 270rwkw@15psi

270rwkw was acheived quite easily but due to the std. bottom end, boost was reduced, to acheive about 255rwkw, and tunning then continued. Hopefully this set-up will last approx 12 months, then the bottom end will be treated to forgies and this combination's true potential will be explored. With forgies i plan to run about 20psi, experiment with both IN and EX cam gears, and have alot more runs to achieve a better tune.

[arm85]

al i know this might be a bit off topic to your thread but i just installed a wolf on my r33 s1, now looking to upgrade the turbo, wondering where you sourced this turbo from and how it compares to a standard hi-flow?

thanks mate if you dont clog up this thread PM me.

[Bunta]

Faaark nice result!!! B) Congrats, you must be stoked

[Al]

al i know this might be a bit off topic to your thread but i just installed a wolf on my r33 s1, now looking to upgrade the turbo, wondering where you sourced this turbo from and how it compares to a standard hi-flow?  

thanks mate if you dont clog up this thread PM me.

<{POST_SNAPBACK}>

Get your std rb25 turbo hi-flowed, either by ATP (Vic) or GCG (NSW), mine still has the roller-bearing core. The hard part is finding the correct VG30 turbo. It has to come from an early model, single turbo'ed, 300ZX, as this will bolt straight on like factory, but has the larger A/R rating. Your best bet is to ask ATP or GCG to source it for you, as they have better contacts.

I bought my hi-flowed rb25 turbo second hand; Paid $900, which included a aftermarket dump/front pipe. This made about 235rwkw, without cams or porting, but due to the small std rb25 exhaust housing and roller-bearing core, it fluttered (compressor surged) at light throttle. I rang ATP and they found the correct VG30 exh housing. I was charged $500 for the housing, machining and fitting. So the whole turbo combo costed me $1400 .

I am absolutely stoked with the result, even my mechanic was grinning from ear-to-ear.

Best part; Turbo still looks factory!

[The Mafia]

Excellent result, but It looks a little laggy.

So its a Standard RB25 turbo, highflowed with a VG30 rear?

I've got a GT30r with a VG30 rear end. Goes for a tune monday morning.

Will definately let everyone know the results.

[Al]

That's why i want to compare results with ppl that have the same turbo.

On the road it is absolutely great, but during the SAU VIC's motokahna day, the lag was felt.

Also on other threads, ppl have mentioned that after adding the VG30 exh. housing, the setup was not much laggier. But all my headwork and VG30 upgrade mods were done at the same time, so i am not sure if the setup should be this laggy.

[Al]

No-one

[Cubes]

Definitely a little laggy.

15 psi by 4810rpm.

Others have stated the GCG/VG30 setup is pretty much all in by 4000rpm. However the VG30 turbine housings used there was the later model Cima/Leopard VG30DET, this VG30 turbine housing also happens to be the same as the R34 GTT turbine housing.

What boost controller?

Edited November 27, 2005 by Cubes

[R31Nismoid]

No-one

Pete is in QLD, so dont expect anything from him for a few weeks.

But his setup comes on boost not too different to stock, its a tad later but you dont notice it that much.

[zoom]

That's why i want to compare results with ppl that have the same turbo.

On the road it is absolutely great, but during the SAU VIC's motokahna day, the lag was felt.

Also on other threads, ppl have mentioned that after adding the VG30 exh. housing, the setup was not much laggier.  But all my headwork and VG30 upgrade mods were done at the same time, so i am not sure if the setup should be this laggy.

<{POST_SNAPBACK}>

the gcg/vg30 is definately laggier than the normal gcg highflow. i'm getting 18psi in 3800rpm & 20psi in 4100rpm, whereas the normal gcg highflow 18psi in 3400rpm.

[Al]

The Wolf3D controls boost, using the factory soleniod and actuator. We are going to be playing with actuators and also other components, mechanic is fairly confident that he could get it spooling faster.

[benl1981]

Zoom - Are you stilll around?

I just got my VG30 highflow BB and it isn't too bad on lag, but quite a lot less responsive to stock. I haven't had a tune yet so all the AFR's could be out the window, since I have fitted a Z32 afm and just made some corrections.

Zoom - Did you get a bit more response from your VG30 highflow after tuning? Or was the difference still about 400-500rpm.

It builds boost a lot slower now. You have to be above 3000rpm to get some decent acceleration now. Whereas before from just over 2500rpm in 2nd would be fun.

It has an awesome top end, though Im still only running 9-10psi. Can't wait for injectors and tune..hopefully running about 17psi.

Hope I've made the right decision since I'm only aiming for about 230-240rwkw. Will the VG30 Hi-flow make that target easier (maybe with less boost) than the rb25 hi-flow?

Edited October 9, 2007 by benl1981

[1400r]

so what vg30 rear housing do you need?

got 6 or 7 vg30's at work but seeing as there in good condition and the rb20 boys love them there not

just the price of the rear housing

[benl1981]

Look for "OP6" printed on the exh housing. They are the ones you want.

Anyone help with my query? cheers

Edited October 9, 2007 by benl1981

[NYTSKY]

I think mine is laggy also.Full boost doesnt arrive till 3800.But when it hits its awesome.Mods in sig.

[benl1981]

Thanks Dave.

250rwkw - bit of a monster hey! Is your turbo a GCG?

Just looking at old videos of my car accelerating in 2nd. Used to get 8psi by 3000rpm. In 2nd I reckon it's more like 8psi by 3800rpm now...

It has lost some of the crispness at low revs. I guess once its tuned when you want to hit it it will go hard, but for the street I reckon that little stock turbo was pretty fine.

[benl1981]

bump

[1400r]

sweet works got 3 op6 vg30s

[Bass Junky]

I run this turbo.

The standard R34 GTT turbo has the "VG30" turbine housing.

I run GCG high flow and some other bits and pieces and make full boost by 3000rpm, any gear, any time.

Fat power curve.

I highly recommend it, my tuner tell me that he's never seen one like it that spools so quick.

She's a bit backed up at high rpm, but this is because of the size of the rear housing. it needs to be a little bigger to support more kw without running on detonation.

[benl1981]

Was it always that responsive? Or did the tune help? How about boost control?

Edited October 10, 2007 by benl1981