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Upgrade Rb 20 Or Put Rb 25 Or 26 Into My R32 Gts-t?

335

By 335,
in Engines & Forced Induction

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335 Rising Star

335

Posted
Posted

Hello

I am wondering which is best and makes more since money wise, to upgrade my RB 20 or put a RB25 or 26 in.

My goal is 300 plus horse power, 350 if possible. I want to have a car that is quick and good mid range which can hit it if I have too. I do not want a laggy car.

Is it better to put a RB25 or 26 inside?

I live in Japan, so I will buy parts here, cheaper. My R32 is manual, so besides engine, wiring harness, computer, and transmission from a R 33 or GTR what else would I need?

Or should I build my RB 20?

Help please

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R31Nismoid Grand Master

R31Nismoid

Posted
Posted

220-250rwkw.

RB20 will do it safely enough, as will a RB25 or 26

Just comes down to how much you want to spend, of which you've not said.

Pretty basic though either way.

RB25 and put a GT3071 on it IMO, same as the billions of other people before you now.

GTScotT Grand Master

GTScotT

Posted
Posted
RB25 and put a GT3071 on it IMO, same as the billions of other people before you now.

+1

I do however also have faith in a basic RB26 swap. The RB26 will land you more than what you are looking for on OEM parts. The RB25 will require a little more money thrown at it (ecu and turbo upgrades) to make that power.

You can expect 260rwkw~ from an RB26 with exhaust, boost and remap (the stock ECU is remapable). The same mods from an RB25 will see roughly 200rwkw (but you will need slightly more than just an exhaust and remap).

GL.

335 Rising Star

335

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Posted
220-250rwkw.

RB20 will do it safely enough, as will a RB25 or 26

Just comes down to how much you want to spend, of which you've not said.

Pretty basic though either way.

RB25 and put a GT3071 on it IMO, same as the billions of other people before you now.

Well

I would put the engine and transmission in with help from people who have done engine installs .

I estimate that I can find a 26 engine for free(someone has one in storage but has abandoned it possibly) or get one for about 1-2000 dollars.

So my price range is about 3-4000 dollars to do this. Also Rb 25s are about 500 dollars used here. So thats even cheaper.

I am wondering if it makes since to put a bigger engine in instead of modding the RB20. All work for the install can be done by myself and help from people who know what they are doing.

What is this slump thing that I read about here with the RB 26 that needs to be modified to fit the R32? Is this only if I do not use the GTR transmission? I am looking to use the R32 GTR engine and transmission if I go the RB26 route.

What are some bad points about the 25?Help please

Sheriff Wan Proficient

Sheriff Wan

Posted
Posted

Hey mate,

For $500 you can't go past the RB25...

When you put an RB26 in you will have to modify the sump. This is due to the RB26 being a 4 wheel drive motor so you will have to look after the front diff as your GTSt doesn't have one...

Hope that helps.

335 Rising Star

335

Posted
  • Author
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if the 26 is free then i think you know the answer

Just if I do the 20 besides exhaust, intake, inter cooler, bigger fuel pump, injectors, head gaskets, ecu tune, what else would anyone recommend I do to put the 20 at 300hp or over?

335 Rising Star

335

Posted
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the biggest difference between a 20 putting out 300hp and a 25 putting out similar power will be the low down power. the 25 will leave the 20 for dead in the lower rev range

I know the low end is not so good. How can I improve on the low end in the 20?

bubba Grand Master

bubba

Posted
Posted (edited)
*note car will be off the road for years...

wut? my car was driving with the 3L for nearly two years, the reason it is off the road now has nothing to do with the fact it has a 3L. If you really must know, the whole RB30DET conversion was done in a weekend. Drove it in Friday arvo, drove it home in the wee hours of Monday morning. It's not fkn rocket doctory.

My point was, there's not a whole lot you can do to get more low down out of the RB20.

Edited by bubba
SimonR32 Grand Master

SimonR32

Posted
Posted
wut? my car was driving with the 3L for nearly two years, the reason it is off the road now has nothing to do with the fact it has a 3L.

My point was, there's not a whole lot you can do to get more bottom end out of the RB20.

N2O haha

I'm going to have a crack at some 50/50 E85 soon and see if we can gain some bottom end grunt :D

bubba Grand Master

bubba

Posted
Posted
N2O haha

I'm going to have a crack at some 50/50 E85 soon and see if we can gain some bottom end grunt :blink:

bah at quoting before I edited :D

I'd love to run straight E85 but until it's readily available over here (read: not having to buy it in 200L drums) I cbf.

limpus Mentor

limpus

Posted
Posted

An rb20 will always be alittle doughy down low....its inherent in the design of the engine...small capacity and short stroke...there is not much at all you can do for it down low...just make sure it screams once it comes on boost...

And IMO...if 300-350rwhp is the goal...the rb20 will make it quite easily...and it'll be a heap of fun too...and if necessary...for that extra kick in the pants...run E85...the extra ignition timing you can wind in will make it a lot more responsive...

335 Rising Star

335

Posted
  • Author
Posted (edited)
An rb20 will always be alittle doughy down low....its inherent in the design of the engine...small capacity and short stroke...there is not much at all you can do for it down low...just make sure it screams once it comes on boost...

And IMO...if 300-350rwhp is the goal...the rb20 will make it quite easily...and it'll be a heap of fun too...and if necessary...for that extra kick in the pants...run E85...the extra ignition timing you can wind in will make it a lot more responsive...

I do not want to be a weak geek on the street. I am not looking to become fasty man, but I dont want to be passed by VW or Non STI Subarus or The ugly Nissan Fugas and their so called Skylines that came out a few years ago, and mazadas and S-14's and S-15's.

I want to be able to hang with the Toyota Mark IIs and R-34 GTTs and others..

Edited by 335
Spurdo Experienced

Spurdo

Posted
Posted (edited)

if you want to "hang" with the R34's then forget about the rb20. they are a waste of time IMO. if you want more low end out of it without going broke then do what everyone else before you has done and get an rb25. for your power target the rb25 is more than adequate and very cost effective.

it is by far the most economical way to make more torque

but then im biased, i have an r32 with an rb25 and i love it! and i've always been of the opinion that building an rb20 is a waste of time. you can polish a turd all you like but its still a turd.

Edited by jonboy

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