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Well as from my sig you guys can see some of my cars' stats.

I now have a RB25DET with a stock ceramic, ball bearing RB25 turbo. I am running 291rwhp @13psi

It will eventually blow up, and may go into the engine. I can't afford to fix that.

So I have a VL T3 turbo from a RB30ET which is steel wheel'd and has journal oil bearing. It is watercooled.

So anyway. I want to slap the T3 on the RB25DET. I only want to run the 15 or so psi the T3 is good for so the car can make 300rwhp and not be laggy. I also have all the water and oil lines from both turbo's and the dumpipe/wastegate setup for the T3.

Would it work?

Edited by reNEGaDe88
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Well the RB25DET turbo is a certain size right. It was a T28 with a T3 flange. It was undersized for a RB2DET as per factory standard. It is good for 300rwhp, but usually at like 14 or 15 psi. At that pressure the ceramic rear wheel is likely to shatter.

Now the RB30ET is a T3. So its slightly bigger. Its has a steel wheel so it won't blow up. But I hear they run out of puff at 15psi+. So if I run the T3 on the RB25DET, then in theory it should still make 300rwhp.

RB25 turbos dont make a legitimate 300rwhp, i dont know who's been telling you that, but its wrong.

Its more accurately 260-270rwhp.

Back to the VL days... i dont remember many (if any) making 300rwhp on stock turbo's

I got 291rwhp @ 13psi on a stock RB25DET with wolf 3d v500, 3" zorst with custom dump, FMIC. Dyno could have read high, but thats fine. So the T28 @ 14 psi ~ T3 @ 15psi, at a guestimate.

I know T3's don't make 300rwhp on standard RB30ET' with FMIC and zorst. But with the RB25DET having DOHC and a higher compression ratio, I think its possible. The the engine is down 500cc, the turbo is a bit bigger, not ball bearing and not ceramic so it would have a bit more lag. But i reckon it would even out.

I literally just want to replace the stock 25 turbo with a steel one so its reliable.

I have the T3 turbo, lines and dump pipe. I don't mind getting a custom front pipe to match, and a few turbo lines to get it connected. I think I would just have to rotate the comp housing. So it would cost ~600$ instead of 2000$ for a highflow.

I got 291rwhp @ 13psi on a stock RB25DET with wolf 3d v500, 3" zorst with custom dump, FMIC. Dyno could have read high, but thats fine. So the T28 @ 14 psi ~ T3 @ 15psi, at a guestimate.

I know T3's don't make 300rwhp on standard RB30ET' with FMIC and zorst. But with the RB25DET having DOHC and a higher compression ratio, I think its possible. The the engine is down 500cc, the turbo is a bit bigger, not ball bearing and not ceramic so it would have a bit more lag. But i reckon it would even out.

I literally just want to replace the stock 25 turbo with a steel one so its reliable.

I have the T3 turbo, lines and dump pipe. I don't mind getting a custom front pipe to match, and a few turbo lines to get it connected. I think I would just have to rotate the comp housing. So it would cost ~600$ instead of 2000$ for a highflow.

me thinks it was a very happy dyno then.

my R34 with powerFC manages 255HP atw on 14psi sooo i highly doubt it.

i have done this swap on my car for the same reason you did. i regret doing the downgrade (is what i call it)

The VL turbo will give you a 20hp difference. and in difference i mean 20hp LESS power then the stock rb25 turbo.

Keep the 25 turbo. drop the boost 1 or 2 psi and enjoy the car how it is. Do not put a VL turbocharger on it. They are garbage.

all i remember is back in the day before i was a tuner, i took a step backwards. the car was more laggy and slower and also only made about 20hp less then others had on their cars. they are just not a good upgrade and the VL turbo i had was a high flow! with bigger compressor and machined front housing by Mr Turbo in QLD

Thanks heaps for the info guilt toy.

So you didn't put a stock T3 VL Turbo on uir RB25DET? You had a T3/4 highflo?

How can a T3 which is a bigger turbo make less power. Mine isn't hiflo so it won't be that much laggier than stock 25 turbo

Its simple, its not a bigger turbo at all. Throe in a crappy exhaust housing and it makes it even worse. FYI teh rb25 turbo is a t3

Yeah the exhaust housing does not look very good, especialy with the wastegate flap in the dump pipe design which pretty much gives you 0 options for a 3" dump pipe. they are known for cracking around the wastegate hole as well. The dump pipe design is crap and the turbocharger uses plain bush bearings and older designed wheels etc etc.

I suggest you sell the turbocharger and try find yourself a VG30 or R34 turbocharger!

No, a RB25DET turbo is a T28 with a T3 flange. The VL Turbo is T3.

The VG30 turbo's in VG30DET design are 90% the same to RB25DET turbo's. Ceramic, ball bearing T28. It just has a slightly larger exhaust housing. = makes a good hiflo. Not a worthwhile upgrade for RB25DET.

The VG30ET tubo's are 90% the same as the VL T3 turbo's. Oil journal bearing and steel. So the same.

The R34 turbo is nylon and ball bearing. Has a larger exhaust housing, so it would be ok.

EDIT: Has anyone bothered to put a R34 Neo turbo on a RB25DET from a R33? I thought even the stock Neo turbo's don't like 14+ psi cos they are nylon = also shatter at high rpm

Edited by reNEGaDe88

The facts about what people call a VL Commode T3 .

I've actually got the compressor wheel and housing right next to me ATM and they are not what you'd call healthy or along modern lines for a twin cam four valves per cylinder 2.5 L six .

What everyone forgets about the RB30ET was its garden variety cylinder head and its soft soft soft state of tune . You don't have to throw much more air down the hole of a 3L six to make it torquier than the NA RB30E .

Off the top of my head they made a whole ~ 153 Kw std , had a very mild cam , low static compression ratio and no inter cooler .

Those turbos were a reasonable upgrade for early FJ20ET's which made ~ 147 Kw from 2L and four cylinders .

Really the main differences between the early FJ "T3's" and VL "T3's" was the slightly larger AR comp cover and comp wheel trim , from memory the VL was 60mm 65T and the FJ 60mm 55T .

What Nissan did back in the 80's was opt for Garrett small turbine series T3 cartridges and add turbine and compressor housings made by someone else , that's why the comp covers have "Nissan Motor" on the comp cover with a Nissan emblem as well .

The favorite trick was to bore the small turbine series Nissan turbine housings out for larger turbines ie TB31 ones and use larger T04B compressor wheels - or the 299-4 wheel which was the Buick Grand National comp wheel . They don't work very well , the only ones that did were a small number Fred from Turbo Logic made up and they were based on the RS500 Sierras 0.63 AR turbine housing designed around TB31 turbines .

You may be surprised to learn that the VL T3's comp wheel is smaller that the RB25's Hitachi wheel , you could look at is as the low tech grand pappy to the 60mm GT wheels in the GT2860R series turbos .

I wouldn't bother with the VLs dinosaur , it would cost good money to get it fitted and I think you would be disappointed with the results .

Ceramic turbines can be a liability but only usually if pushed beyond their limits .

The first R33GTST I ever got in had more than reasonable performance and it still had its std turbo , the mods were a pipe kit and GTR IC , and a ported head with over sized exhaust valves and slightly higher CR . Cams were std and the computer was a PFC .

A .

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