RB20 Questions

[VLRB20]

just wondering if anyones knows the answers to a few of my questions...

all questions are related to a rb20 computer...

do they have speed limiters?if so what are they?

when cutting the speed sender wires at the back of the ecu... does it effect anything else?

i know it has rpm limiter, but what is it?

what is the boost cut set at?

what is the max. boost you can run (SAFELY) with stock internals,fmic and exhaust?

does anyone know the most power you can get with these mods?

cheers

[VL-TRBO-RB20]

well i know you have a rev limiter at 7000 - 8000rpm

i dont think you have a speed limiter coz ive been off my clock and nearly hit the button thing

i dunno what the boost cut is set at... ive got a T04 and im running 15 psi with a stock intercooler...

i wanna get a bigger FM n try run 20 -25

[adrnln]

I have been told don't run the stock ceramic turbo over 14psi 1 bar as bad things happen ( boom) It is usually ideal to get a steel wheel in the turbo.

just what Iv'e been told and i'm not the one to try the theory out

Andrew

[cefiro]

limited to 180kmh, I know you can cut the wire although not sure which one it is on the cefiro may be different.

rev limiter @7600

not sure on boost cut mayny 14psi, I think most people will agree that its more your standard turbo going to crap itself if you run much more than 14psi through it as its got a ceramic exhaust turbine which is fragile. but speak to people and see what they say. I think for $3000, you can almost get away with a new turbo and ecu remapped which will better your chances at running more boost and up your power a heck of a lot.

but not everyones got $3k to blow in one hit.

[Ceffo]

VLRB20:

Im assuming rb20 computer hasnt been remapped etc.

1. Yes they do have rev limiters. On mine its 7300-7500 revs.

2. Speed limit is alo rectriced to 180km/h on standard rb20's

3. Its wire #53 on the ECU harness to disable the 180 kph speed cut. It also disables the hicas. Whihc most guys disable anywayz.

4. With stock internals,fmic and exhaust(im assuming trubo bacj exhaust here) i would be running only 1bar max.. even that. Try and get it dynoed tuned b4 trying this thou. 40 bux compared to a new engine/turbo

5. Ive seen my mates on with same mods get 134rkw (dismell numbers i know)on 1bar boost. Soory man but its a sad fact of life with the rb20

[cefiro]

I dont think the rb20 is bad at all, I have a few mods on my car and have taken out ss commodores, modified wrx etc, I have a fmic, 3in from turbo, hks2535, boost running about 1.2bar on a tuned rom. I would say you are half the way there just need turbo and tune. should be able to make around 200+rwkw. thats nothing to smirk at.

I recon you can tune your car with your mods for around 160rwkw, if you up the boost. thats around 220kw at the flywheel, pushing a car weighing around 1360kg is not to bad. power to weight of 6.1 kg/kw. you are going to be competitive against most cars you will run against, such as ss commodore, xr6, etc.

its definitley worth getting a run on a dyno if you can and see how you go but as ceffo said no more than 14psi seems to be the general concencus of the limit of your turbo.

[VL-TRBO-RB20]

ive taken out VY SS utes its fun

[VLRB20]

i have heard about cutting the wire, and the 14psi but was just asking opinions...yeh its a turbo back but its in a vl calais so its pushing 1600kgs... but anyway thanks....

[VLRB20]

i have been told with my mods i should be able to get about 160 at the wheels with 14psi! i have seen it a couple of times but its hard to compare...

[BHDave]

For 160-165rwkw, which is the absolute maximum you are going to get with the stock turbo you will need a full exhaust, pod filter, front mount, some kind of boost controller or hks actuator and run no more than 13psi as the stock turbo is at the edge of it's efficiency at this point and only makes heat after that and so the engine likes to ping and thats about it. And i ran about 16 degrees base timing. Pretty easy really. But expect your turbo to die quite quickly at these power levels. Mine actually died at after about 6 months on 12psi.

Stock fuel pump is fine at this sort of power, mixtures are fine but a little rich in the midrange though not by much and spot on at the top end (or atleast mine were at 163). AFM is maxing out at this level, injectors are generally running pretty hard with the stock pump too. for more power you need a turbo and management.

My car had no boost cut.

Cutting the speed sensor wire will effect the speed sensative steering as well and bugger up the automatic box's shifting if you have one.

[dangerous_daveo]

I'll agree with Dave on that one. I had my boost on 13-14psi, now its back on 12-13psi and feels heaps better. Im still running the stock cooler tho. And I got 142rwkw with that set up, but Im still running a stock dump pipe.

[someonestolecc]

god daveo that's a big figure for stock turbo.. should be nice in the cef!

As for speed cut I don't think the VL would have speed cut as it's aussie vehicle? I mean I've never owned a rb20 or commo but I don't see why it would have one (it's not an import).

My boost is currently about 13-14 and I think its slow (i'm getting used to it).. i'm starting to want a bigger setup.. sigh this is bad.

[dangerous_daveo]

If the conversion has had all the wires and sensors hooked up too, then its going to work just like any other RB20.

[inark]

as stated dont run anywhere near 1 bar boost on a stock turbo with no retune unless u like seeing what happens to an engine when it leans out

i thought id have a little fun one night and upped the boost to 16psi lol

soon as i hit around 5000rpm *blat blat blat blat* lol

straight back down to 13psi

[someonestolecc]

If the conversion has had all the wires and sensors hooked up too, then its going to work just like any other RB20.

Ah conversion. I thought it was a factory rb20 - oops that ain't possible.

[dangerous_daveo]

Ah conversion. I thought it was a factory rb20 - oops that ain't possible.

Not unless he was lucky and got a prodotype Vl with an RB20 in it

But yeah, Im also running a RRFR (riseing rate fuel reg) so Im not overly worried about leaning out, just my fuel bill

[VLRB20]

thanks guys for the input... yeah they speed limiter is definately hooked up, its a manual so no need to worry there... so are there any steel wheel turbo's out there that my ecu with running efficently?vg30?