Vg 30 Turbo Onto A Rb20

[Drift Freak]

I'm thinking about upggrading my RB20 with a VG30 turbo high flowed by GCG turbos in sydney. I was wondering if anyone out there has tried this combination and were the oil and water lines compatible or do i need to manufacture new ones. Also what sort of power figures did anyone end up with???

[blackprincegts]

1 of my mates has an r31 wagon with rb20det and vg30 turbo, running a microtech and extra injector in the crossover pipe. he is making 152rwkw's on 10psi but i must say that i feel that his car is slower than when he had the stock turbo on, VERY LAGGY. iv driven it heaps of times and i personally prefer my wifes complete stock 32 gts't auto (which actually pulls away from his car ina drag) because theres barely any lag.

On the other hand, another of my mates has a 31 sedan with rb20det, with vg30 turbo also on 10psi running stock ecu with no remap and thats about it and his car consistantly made between 166 and 168rwkw's on the same dyno as my other mate was on. Iv been in his car and it absolutely hooks, pushes you back in your seat from around 3000rpm which is practically like the stock turbo.

i think my mate with the wagons motor is just a piece of poo though, its always been a wierd motor, laggy for some reason, even when stock turbo was on it lagged like hell.

so yeah if going by the 2nd result then i think youd be happy with the vg30 turbo highflowed running 14psi i rekn you could make maybe 180-190 at the wheels..

cheers.

[blackprincegts]

oh and im 99.9% sure that they used the stock oil and water lines from the rb20det when installing the vg30 turbo, ill ask them and post up again if i find out otherwise.

[WazR32GTSt]

can you say lag?

its laggy enough with an rb25 turbo...

[GTAAAH]

off topic but how much laggier exactly? What RPM you got boost kicking in and out?

Getting mine in the mail today, i thought they were only the tiniest bit laggier (series 2 turbo off a 32/33)

And yeh i also heard that the vg30 is hella laggy, but it bolts str8 up.

Edited July 26, 2006 by r32 gts-turbo

[MANWHOR3]

Well, people say 4-500 rpm later. The rb20 with stock turbo isn't exactly a response machine as it is.

Sydneykid says that the rb25 turbo flows about 50% more than the rb20 unit. So yeah, of course it will be a bit more laggy.

But that's the price you pay for more power.

[Munna1]

Will be very laggy mate rb25 turbo, GTSS or a 2530 would be a better match

[r33_racer]

The joys and compromises of turbocharged engines. Some awesomely magical turbo with a malleable rear end that can grow or shrink the AR based on exhaust gas flow as to eliminate all lag down low but not compromise top end power when at full song....a 1000hp turbo with no lag!! big smiles for everyone. One day it will come...one day.

[GTAAAH]

ahh 4-500 later isnt so bad, just have to drop it higher when taking off. As for a 2530 i thought that'd be bigger again price is sorta crazy for those.. Is a 33 turbo "big" for a rb20, in relation to other commonly used turbo set-ups for acceleration? Lag isnt such a bad thing anyway, part of the fun having a turboed car is watching the revs build up then getting smacked back into your seat ;

I'll be dispatching a ransom notice to you drift freak that will stipulate when, where and at what price, you can get your thread back.

Edited July 27, 2006 by r32 gts-turbo

[WazR32GTSt]

rb25 turbo on rb20 is not much laggier (if at all) than stock..

i was referring to the fact that the rb20 is laggy. whatever turbo.

maybe not if a turbo off a suzuki cappuccino was bolted on?

hmmmm 6*mini-turbos? on a wicked custom exhaust manifold?

the closest thing to power without any lag...

[Rolls]

The joys and compromises of turbocharged engines. Some awesomely magical turbo with a malleable rear end that can grow or shrink the AR based on exhaust gas flow as to eliminate all lag down low but not compromise top end power when at full song....a 1000hp turbo with no lag!! big smiles for everyone. One day it will come...one day.

They already exist, not exactly as you described but they are called variable vein or something. On audis etc, have instant boost with no lag.

[Shaolin242]

They already exist, not exactly as you described but they are called variable vein or something. On audis etc, have instant boost with no lag.

theyre out now dude - VCT and VGT turbos - Variable Vane/GEometry Turbo's - Porche 911 turbo has them now, the A/R shrinks at low RPM and increases at high RPM eliminating lag and giving a good top end...makes a virtually lagless system on a 500hp car...

[TTT]

Sydneykid says that the rb25 turbo flows about 50% more than the rb20 unit

If you’re going to quote the man at least get it right dude.

[Cool Hand Luke]

I really doubt the fact that an RB25 turbo on an RB20 is laggy. It doesnt have NA instant response, but considering the power gain i thought it was a more than fair trade.... not that i tried to drive it hard below 3000rpm.... its an RB20 afterall. If thats what your looking for, maybe your better off with an RB25/30 because even with the stock turbo, its not that impressive that low in the rev range.

Even my last car which had an SR20 was thought to be "laggy". To be honest, when you drove it correctly, it wasnt a problem... you just had to adjust to the fact that it wasnt transmission smashing instant hp, and below where it made boost not to bother.

It was, when driven how it should be, awesome, and made awesome power from 4000-75000rpm which is as good as most N/A 8's with similar power would do.

In the worst case senario with the RB20 when the boost response wasnt instant, you could just pop the clutch and it would spin the wheels at 70kmh in a 180sx... Not to bad for a more or less stock engine.

From my time on this forum, and everything else i've read, my advise would be (and im not a turbo guru). If your looking for around 180-200rwkw go for the rb25 turbo... its an awesome upgrade and without many sacrifices. 220-250 look at your 2530/gtrs respectively...

Edited July 27, 2006 by Cool Hand Luke

[Angry]

i ran one on my rb20 for nearly 12months .....on 1bar.... spooling by about i dunno 2800 , 10psi by 3700-800 & 1bar say 4500 holding it to 7500 .... not 100% on the rpms coz i dont really drive staring at my boost guage. i also ran a turbotech bleeder which helped quiet well for spoolage. .. without it .. it was pretty bad.

powerwise .. at a guess iwas creeping up to 160rwkw with th auto

0-100 in 6seconds. very similar to a 25 turbo on my m8s silvertop .. just fractionally later that my opinion though

my turbo has a ceramic rear wheel on it.

only reason i put it on .. was the turbo was very cheap .. and as its first turbo car i wanted to see what everyone REALLY meant by rb20 lag monster. very lack luster for response if u want "go" liek a stocker turbo

if u drive in traffic alot ..its pretty useless.....alright if ur going in a straight line for a while..... shit for track or twisty use unless ur in the revs the whole time.

Edited July 27, 2006 by Angry

[Cubes]

Stepping up to a much bigger turbo (vg30 highflow) will result in the first 2 gears being useless, and I mean useless, almost to the point where it feels like its hardly boosting.

I ran a late model vg30det turbo on my rb20det, first gear felt a little crappy as it didn't really boost and in the later gears it lost that hard snap in the back turbo feel, it came on progressive. Which is quite obvious really, its a turbo designed for a 3ltr with lots of exhaust flow they don't want the turbo spooling at 1500rpm now do they.

The vg30det turbo is nothing more than an rb20det turbo with a larger compressor cover and larger turbine cover.

So yes.. the vg30 runs the same compressor and turbine wheel as the rb20 turbo.

Nissan have done this as to shift the spool and power band if you like higher up in the rpm on the big 3ltr yet still make lowish power levels. If they were to leave the same rb20det comp and turbine covers on the turbo it would spool too early and power would nose over hard after 4000rpm.

This is what makes it a bad match for the rb20, the turbo favours exhaust flow, which is not what you want on an rb20.

As said.. go the rb25 turbo or step up to a 2530 and beyond but do think about your goals, a street car that doesn't boost in the first 2 gears is not fun.

[Drift Freak]

Cheers guys, invaluable information all round. I can see your theory about the air flow needed Cubes and i like 1st and 2nd. I think a R33 2.5ltr turbo will be the choice, extra power stock oil and water lines can't go wrong i suppose without busting the bank.

[WazR32GTSt]

good idea mate..

i did this recently but also went some adjsutable cam gears to help with early spooling. check out my results with an auto transmission: http://www.skylinesaustralia.com/forums/in...=115398&hl=

[Brocaine]

I had a VG30 turbo on my Cefiro. It made 167kw@wheels on 13psi.

Wasn't really that laggy at all, infact I thought it drove pretty well.

[coprims]

RB20 with VG30 Roller + FMIC + 3" turbo back exhaust + remap made 196rwkw on my laurel

and as for the nards calling it laggy...BAH

no effing way...make sure you get it remapped by Jeff at The Speed Lab you will have no dramas with lag...