RB20DETT TwinTurbo2Litre

[r31gts]

i would also re think your oil feed situation aswell..... the t'ed of turbo will get less oil.........

[meggala]

your car will be slow and you injecotrs and afm will max out it will be laggy as they say.

before you go futher have a read of this

http://www.meggala.com/modys.htm

then have a think

on paper it all sounds great but in reality there are issues lag etc.

this set up would be workable on a stock rb25 but did you want to go down that path there is nothing wrong with makig a mistake most of us do it If you want a bit more grunt fit a vg 30 turbo to your rb 20 and that will happily max your injectors and afm wont cost a fortune $4-600.

with the twin set up 5 grand plus will be needed to make the system work at a reasonable level if the manifold is free try it out but only use the stock boost setting till you get it on a dyno you will be coming close to maxing outyour injecotrs and you will blow your motor.

cheers

meggala

[Cubes]

Honestly I think it will lag like hell.

I can get full boost by 2600rpm by loading it up in a high gear.

Generally in second gear I get full boost if powering out of a corner by 3500rpm.

Don't be suprised if you won't get boost in first gear at all.

Remeber its not just the cc's that make a turbo spool quick its also the length of the stroke.

A short stroke 2ltr should in theory take longer to spool the same turbo than a long stroke 2ltr.. Hence 4cyl vs 6cycl 2ltr.

[R32 GTSTT]

ok so there is alot of ppl out there that think its not going to work, well it anit costing much so thats cool. What single turbo would be equivent to 2 RB20's. A TD06?? Ok it will be laggy, but on a dyno with the ecu tuned, who much rwkw would u be predicting?

[Cubes]

In theory again...

The RB20DET Turbo's generally make up to around 160-165rwkw each. So. 2 of them should make around 310rwkw. But that won't happen due to the head becoming a restriction etc.

I'd be quite interested how much power these two turbo's do make actually.

Bit off the topic but looking through my old zoom mag with the bathurst restored gibson motor sport R32 GTR is making me hang out to get my Model Bathurst R32 GTR replica... Cost me $165.

There was 2 left. Now 1...

Didn't have the money on me so I had to slap a deposit down.

[Cubes]

What would be nice is to repaint my R32 to the Bathurst R32 Colours.. Red with a white stripe down it with yellow stripe along the bumpers and a set white GTR Wheels.

I'd wait til i've got the GTR for that..

[R32 GTSTT]

yer that would look very nice, So does anyone know what power a rb20 produces with stock fuel pump, injectors, afm. I heard from a previous post that a vg30 would max out these, what type of power does a vg30 turbo make on a rb20?

[kabab]

Swap them for CA18 turbo's i'm sure that won't be very hard at all..

Its not how much peak power you make its how you get there

[5hift]

ok now before somebody goes off "here we go again" type thing let me explain my goals

I just started toying with this idea as well thinking of perhaps using the 25DET turbo and keeping the stock turbo. Would this also be laggy?

I dont want to make Massive power so yes using a single RB25DET would be sufficient for what i want. (Street quickness not drag monster)

yes 'drop in an RB25' would also be better but i alreayd know all that.

300 flywheel hp is more than enough for me. i just want quick turbo response with decent mid and high rpm performance too (dont we all). so whats the final verdict? RB20turbo + 25DET turbo?

RB20 + CA 18

or 20DET plus 26DET?

or is it possible at all to have a RB20DETT thats not laggy ?

is there a smaller ball bearing turbo that could mate with the stock one to accomplish this?

thanks for the info..sorry for the rambling...partied too hard last night

[BHDave]

2.5 year old thread. Is that a record?

You are talking about sequencial turbos, Ideally you want something smaller than an rb20 one to spool up and something bigger than an rb25 one for top end.

And then you need stupid amounts of time and money to get the whole thing working properly as you will need custom everything on the exhaust side of the engine as well as the compressor outlets.

Before you go any further, take a look at the setup an a 2jz and think about how you are going to make that work on an rb20. Once you've thought about it for a little while, you'll realise that you will get better results for less money by swapping in an rb25, or upgrading your existing turbo to something like a 2530.

[ebola]

? Let me get this straight.

you are making custom manifolds for the twin rb20 setup?

And then plumbing back into the single exhaust right before the cat?

(Just checking I have my facts right)

Question - had you considered an rb26 manifold (and do they even bolt onto a '20) and dump pipe? (EDIT - and turbos)

The setup will be laggier than standard, and probably past the stock injectors - but the boost warnings have all been given (heed them well).

Of course, you already had 1 '20 turbo...

I am actually curious as to exactly when they start producing useable boost. Good luck with the venture

Edited January 4, 2006 by ebola

[paulr33]

just go the 3 litre bottom end conversion, less cost and more bang per buck. do u want twin turbo for reason? you could make more power and earlier with the 3 litre bottom end

[5hift]

Thanks for the responses guys...thing is im in Jamaica (hence my odd posting times ) so "just getting a 3.0 bottom end" isnt gonna be so easy for me.

time and money yes i realise is gonna take a lot of planning but i really wanted to know if this was possible in theory. Of course stock fueling was not a consideration. MOst likely GTR or Supra ( ) injectors and a GTR fuel pump.

I was hoping for a twin turbo setup because if i could get it tuned and running properly it would be superior in terms of power delivery (which is higher on my priority list than peak power)

Yes a custom manifold is also necessary but ive seen it done on the RB25DET(T) on the calais twin turbo thread on this forum.

So what if I ditched the 20 Turbo went with a smaller ball bearing turbo, and then an RB25 turbo?

RE 2.5 yr old thread... hey...at least i can use the search button and didnt post a new topic hmm..maybe i should get a medal

[1400r]

meh waste of time and money on twin turbos if you really want to try and get he best of both worlds why dont you twin charge it .

supercharger and a turbo?

buy a little 4agze s/c and what ever turbo you want and you might get what your after

twin's on a 2lt are never going to be good lag city even with stock rb20 turbos they probably wouldnt start pulling(not spooling) till 3,800

[D-limo]

The gold laurel on my sig runs GTR turbo's on an RB20.. Apparently a LAG MONSTAR...

[5hift]

problem i think is I'm looking for atypical tuning methods. This doesnt sound too encouraging though. Thanks for the info and quick respnses. Bless

[Roy]

If you like the idea of some custom piping and twin turbos, then I don’t see a problem why it cant be a good / fun thing on an RB20. I would be looking at getting some R33 GTR turbos and manifolds, (manifolds flange will require tweaking) and bolting that all up. Odds are much of the std GTR piping will be bolt on, and is often available second hand from when people have added HKS/Trust hard piping kits to their GTRs.

That all said, I think if you are going to do this then you will need nitrous, so when you are tootling around with approx 100rwkws up to 3,500rpm with only about 0.2 bar etc it will make for a reasonably smooth road car. I suppose you would be making 1.1bar by about 4,600-4,800rpm which isn’t too bad considering you should be in the vicinity of 250rwkws peak power.

With the gas im sure you can get the turbos on song a lot sooner and the thing will make good strong power, and considering the cost of the 2nd hand GTR bits, the only major expense will the ECU and tuning.

Provided you are happy to use Nitrous, I think it’s a great idea, at first I didn’t think so, but with a 75hp shot of gas…you have got me thinking….

[Josh]

I was just thinking about the 1g-gte - I know they aren't that great but they have a twin turbo setup on a 2L - would it be possible to use a similar sized turbo, even the same CT12's(Could probably use the CT12A's off a 1J) on an RB20 with the right amount of custom work?? I'm not too familiar with how quickly they spool so don't know how laggy they are.. I think there were two power outputs for the engine(185hp & 210hp I think...), but I am not sure how much power they(turbo's) will handle..

[discopotato03]

R32 GTS TT , I'm not sure for the cost that a TT RB20 could give you any advantage over a larger engine with a reasonably straight forward single turbo .

Nissan sized the GTST's single turbo for 2000cc so in theory doubling the turbine /housing area would also double the boost threshold rpm . Each turbo only has half the number of cylinders and exhaust energy to drive it .

Sounds silly but the turbos designed for a three cylinder 1000 would probably be better for a 2000cc six .

I would not be in any hurry to use a balance pipe on a twin parallel turbo straight six . The reason why they work GTR style is the firing order and exhaust manifold/turbo sequence . 153624 , front back front back front back with no interference . Short three leg manifolds will have less internal volume than the 6 into 1 or 2 . I reckon a split pulsed single manifold ie the cast HKS would be easier to package and suitable single turbos are around .

With the Hitachi turbos its doubtful if you could get small enough a/r turbine housings and if you could I reckon the turbos would surge .

Factory engineering is often hard or non cost effective to beat so if I really wanted to do twins I'd use the GTR manifolds (don't bolt straight up but cheap) and turbos such as GT-SS's as they spool earlier than R32 GTR turbos .

Bottom line , TT RB20 not cost effective .

Edited January 5, 2006 by discopotato03

[NathR32]

Whoa talk about thread revival...