hks 2540r on rb20..what you think

[beario]

COMPRESSOR:

-Wheel- 46 Trim - 51.7 Inducer / 76.2 Major

-Housing- 60 Inlet / 50 Outlet - 0.50 A/R

TURBINE:

-Wheel- 76 Trim - 53.8 Major / 47.0 Exducer

the unit has done 10k..would this be a good upgrade..i have the usual other bolt ons...what charecter-istics would this turbo have on an rb20det..thanks ion advance

[Sydneykid]

Hi Beario, I would have a read of this thread, and keep in mind that an RB20 is 25% smaller than an RB25.

http://www.skylinesaustralia.com/forums/sh...ead.php?t=38372

[bbenny]

i have a 2530 on my RB20, i heard to many stories about the 2540 being too laggy on an RB20.

The 2530 maybe a little laggier reaching 1bar a couple of hundred revs later than the standard item, but mid range is strong and top end difference is awesome.

at the moment im running std computer, untuned. and its putting out 210rwkw at only 0.9 bar. i havent wound the boost up as over 1bar the engine cuts (maxing out AFM i think).

im in the process of getting some GTR cams and adj cam gears to see the difference then get the ECU tuned. i hope to get about 230rwkw, any more and ill be stolked.

I just think that the 2540 would be too laggy. if people are complaining about lag on an RB25 i dont want to know about it on an RB20.

[SLY33]

i reckon! dont forget he is talking about the R version of the 2540, so it would have crazy lag.

[Cake]

beario, GT2540R has a T25 flange.

if you want it to bolt-on to your standard rb20det manifold you are going to want the GT2540.

2540R only has about 20ps over the 2540 anyway.

more info: http://www.hksusa.com/categories/?id=1092

[beario]

gees guys i have bought this turbo now...as no one replied to the thread straight away...so your saying the turbo wont bolt on to my standard rb20det manifold..??and there is going to be massive lag...someone please give me some charecteristics of this turbo on the rb20det...can i have the manifold modified so it fits easily or have i just wasted a BUNCH of money.....

[Sydneykid]

gees guys i have bought this turbo now...as no one replied to the thread straight away...so your saying the turbo wont bolt on to my standard rb20det manifold..??and there is going to be massive lag...someone please give me some charecteristics of this turbo on the rb20det...can i have the manifold modified so it fits easily or have i just wasted a BUNCH of money.....  

Hi beario, you post this question at 1 in the morning, get a reply at 2 in the morning and complain about no one replying straight away. That's a bit harsh. Plus if you had bothered to do a search on 2540's you would have read all that you needed to know.

To answer your question, you can get a bolt on adaptor to fit the T25 flange to the T3 manifold. Your local turbo shop should have them. Or you can buy a T3 exhaust housing for the 2540. Either way, in my opinion, you have a 2540 that has too big a compressor stage for a light tune RB20.

Hope that helps

[beario]

sorry sydney was not having a go...all help was greatly appreiciated...i guess now its bought i had might aswell put it on,and see what its like...in your opinion where will the boost come in...my mods are hks evc,3 inch front pipe,4 inch cat back exhaust,hks air filter,super afc,mines ecu,ported manifold(intake de burred)...will the boost be gradual or all or nothing..thanks

[Sydneykid]

sorry sydney was not having a go...all help was greatly appreiciated...i guess now its bought i had might aswell put it on,and see what its like...in your opinion where will the boost come in...my mods are hks evc,3 inch front pipe,4 inch cat back exhaust,hks air filter,super afc,mines ecu,ported manifold(intake de burred)...will the boost be gradual or all or nothing..thanks

It's a 2540, so it will show all the usual 2540 results. It will have nothing under 3,750 rpm. and go to full boost in less than 1,000 rpm. It will hold 19 psi from there to 6,250 rpm where the boost will slowly taper off to around 15 psi at 8,250 rpm. The slow boost build and rapid transition is because of the large compressor. The drop off in boost is because of the small turbine. It's the standard 2540 missmatch between compressor and turbine.

My suggestions would be;

1. a pair of standard RB26 camshafts, the higher lift will help the response.

2. something to tune the ignition timing, you have fuel correction (SAFC) but no ignition control. This is the most important weapon you have for improving the response.

3. FMIC, you are going to have severe restriction with the standard IC. I would use an R33/34 standard GTR intercooler and keep the pipework short via a 120 degree bend at the throttle body. Use 63 mm pipe from the turbo to the intercooler and 75 mm form the intercooler to the throttle body.

4. A pair of adj camshaft pulleys will also help

Hope that helps

[TTT]

OR

sell it and get something more usefull for your setup..