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Is that good or bad?

EDIT: By the way. I read this old school info sheet form R31 skyline club ( the last of the mass produced aus skylines).

It states tha the RB20DET's should be fitted with RB30ET turbo's for good simple power upgrade. So seeing as many 20's have 25 turbo's I thought a 30 turbo would be similarly good.

Apparently not.. meh

http://wiki.r31skylineclub.com/images/2/24/Nissan6s2.jpg

Edited by reNEGaDe88

Well I'd be using something native to an RB twin cam if possible because it means more factory bits should fit together , less customisation means cheaper conversion generally .

I reckon a ceramic R32 era turbo is a better thing for an R31 era RB20DET if you speaking strictly factory parts .

You may even find that an R33 25DETs turbo works ok but I dunno where the factory management can get you if its expecting to see a really small bush bearing turbo (NICS type thing) .

I've never had one but it sounds like RB20DETs need all the help they can get in so far as getting the turbo pumping goes .

Bush bearing turbos are always going to bit a bit lazy to get going (oil sheer drag) so are often small to keep the exhaust gas velocity up .

You sort of get the worst of both worlds by fitting a larger bush turbo because the turbine housing (VLT T3) is larger meaning the exhause gas speed will be lower from a 2L six at lowish engine revs .

Once the engine revs climb the gas speed comes up but you still have the extra oil sheer drag to overcome so you get two stages or excuses for lag so to speak .

Also T3 era compressors and turbines are pretty dated now days so don't tend to work over as broad an engine speed range as current units .

If you really like RB20s and R31s a later RB20 with its later turbo and engine electrics is a better way to go IMO , an RB25DET better again .

A .

Yeh disco. I didn't see how putting a heavy steel wheel'd, bush bearing turbo would work well on a RB20DET. It would be ultra laggy.

I was just clarifying. That document might have been written in like 1996. So AM turbo's were limited and Silvertop RB20's were not as widely/readily available.

PS. I had the VL T3 turbo on my R31 for 2 years. Ran a bov for 6 months, then got a FMIC and had no bov = flutter. Then for a year I ran a dose pipe. so 1.5 years of compressor surge. The turbo still has very little shaft play. Same as when I put it on 2 years prior. They are 20 year old turbo's. And still going strong. Can't be that bad.

Is that good or bad?

EDIT: By the way. I read this old school info sheet form R31 skyline club ( the last of the mass produced aus skylines).

It states tha the RB20DET's should be fitted with RB30ET turbo's for good simple power upgrade. So seeing as many 20's have 25 turbo's I thought a 30 turbo would be similarly good.

Apparently not.. meh

http://wiki.r31skylineclub.com/images/2/24/Nissan6s2.jpg

Ancient tech document.

I would ignore that.

If for whatever reason you had to use one of those Nissan/Garrett T3s I would have picked on the slightly smaller variants off a later intercooled FJ20ET or Z18ET . They had 0.48 AR turbine housings (vs 0.63) and smaller trim compressors , I think lower ratio compressor housings as well .

Your calls but really the only thing that's right is the mounting flange on the turbine housing , the rest shouldn't have escaped into the 1990s let alone the noughties ...

Wouldn't the youngest of the VLTs be more than 20 yrs old ?

A .

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