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Ok so it's come to a point where i really probably need to spend a bit of cash on the ol RB20 to keep it running reliably.

i.e Coilpacks, Timing belt, water pump, idler/tensioner pulley etc etc.

So i was considering an upgrade rather than sink my cash into the RB20.

Heres basically where I'm at. RB25 or SR20.

Let me frame the case each way. First of all I guess its important to point out that it's street driven on a daily basis, in traffic, and i do NOT want to be doing that with 400hp. I'm thinking around 250rwkw (Tops. Probably more around 200.) with response being the key. I do however intend on getting into a bit more circuit racing and maybe some drift events soonish. Trying to set it all up first.

Now that i've mentioned that onto the two choices.

Rb25

Pros

-Can keep the ATTESA system as long as i source it from a Stagea and run a GT-R power fc. (So I'm told.)

-Relatively cheaper if i keep the RB20 Box (Should maintain 200kw?)

-Good mid range and a fairly common swap into 32's meaning info and support should be readily available. (Ideally)

Cons

-Heavier.

-Have to get one from a Stagea or can i just get the stagea front diff/sump assembly and bolt it up to a standard rb25? Also am i gonna run into issues with my rear diff being 4.3? I THINK Stageas run 4.1? Should i just upgrade my rear diff to a GT-R item? Also running 4.1 from memory.

SR20(Please note with the SR i wont bother trying to keep the ATTESA and will just rip it all out.

Pros

-Lighter (Sr<RB in terms of weight, plus the weight savings of removing the transfer case, and front driveshafts and diff etc.)200kg?

-Better for street use being smaller capacity and easily tuned for the power range im thinking about (Yeah sounded dumb to me as well)

Cons

-More expensive as i will have to run the sr box as well, S13 Crossmember for the engine, and im not sure about the geearbox crossmember.

-Removal of Attesa means it might as well be a GTS-T

So i guess thats kind of where I'm at. I know theres a bit of infor on RB25 swaps and Im sure I could find some about SR swaps too, but I guess my case is probably a bit more peculiar being a GTS-4. I'd rather not go down the path of RB26 as I dont need the power that they entail.

Can anyone shed any light on what either swap will entail and what they think would probably be the better solution.

Cheers,

Greg

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Just briefly, based on my own experience fitting the Stagea engine:

The Stagea diff ratio is different to the GT-R (4.083 vs 4.111) You can either swap the diff from your RB20 into the Stagea engine, or swap the Stagea rear diff internals into your R32 rear diff. I initially did the front swap, then later swapped to the Stagea set (RB25 just has too much torque to require 4.375 gearing). If you run Stagea gearing, replace the speedo drive in the gearbox with the GT-R item.

I'm almost certain that the Stagea sump is not a simple bolt-up to a RWD RB25.

The original R32 gearbox seems more than capable of handling the torque. When mine was first tuned (Wolf 3D v4+), I was pushing 180 awkW (easily in excess of 200 rwkW).

Ok so it's come to a point where i really probably need to spend a bit of cash on the ol RB20 to keep it running reliably.

i.e Coilpacks, Timing belt, water pump, idler/tensioner pulley etc etc.

So i was considering an upgrade rather than sink my cash into the RB20.

Heres basically where I'm at. RB25 or SR20.

Let me frame the case each way. First of all I guess its important to point out that it's street driven on a daily basis, in traffic, and i do NOT want to be doing that with 400hp. I'm thinking around 250rwkw (Tops. Probably more around 200.) with response being the key. I do however intend on getting into a bit more circuit racing and maybe some drift events soonish. Trying to set it all up first.

Now that i've mentioned that onto the two choices.

Rb25

Pros

-Can keep the ATTESA system as long as i source it from a Stagea and run a GT-R power fc. (So I'm told.)

-Relatively cheaper if i keep the RB20 Box (Should maintain 200kw?)

-Good mid range and a fairly common swap into 32's meaning info and support should be readily available. (Ideally)

Cons

-Heavier.

-Have to get one from a Stagea or can i just get the stagea front diff/sump assembly and bolt it up to a standard rb25? Also am i gonna run into issues with my rear diff being 4.3? I THINK Stageas run 4.1? Should i just upgrade my rear diff to a GT-R item? Also running 4.1 from memory.

SR20(Please note with the SR i wont bother trying to keep the ATTESA and will just rip it all out.

Pros

-Lighter (Sr<RB in terms of weight, plus the weight savings of removing the transfer case, and front driveshafts and diff etc.)200kg?

-Better for street use being smaller capacity and easily tuned for the power range im thinking about (Yeah sounded dumb to me as well)

Cons

-More expensive as i will have to run the sr box as well, S13 Crossmember for the engine, and im not sure about the geearbox crossmember.

-Removal of Attesa means it might as well be a GTS-T

So i guess thats kind of where I'm at. I know theres a bit of infor on RB25 swaps and Im sure I could find some about SR swaps too, but I guess my case is probably a bit more peculiar being a GTS-4. I'd rather not go down the path of RB26 as I dont need the power that they entail.

Can anyone shed any light on what either swap will entail and what they think would probably be the better solution.

Cheers,

Greg

My opinion - it would be cheaper and quicker to get 200kw out of your present motor and then save up for a R32GTR or R34GTT!

if u put in an rb26 ur gona have the power u want with only a couple of bolt on mods like exhaust, cooler and abit more boost.

in my opinion it would work out cheaper seeing that it would be a much easier swap and your not going to have to buy as many parts to achieve your power goals

apart from all the headf**ks putting them into an earlier model car (It might be a tad easier on a R32 but I've seen it done twice on HR31's and both times, the actual fitting of the motor was fine, but getting it all up and running was a long and drawn out process)

I guess it's a little more involved but have you thought about going down the path of a 25/30?

I'm not really an expert on rb20's but I think you'll require the sump adapter which are about $600, an rb25 head and associated intake piping but the turbo manifold & lines should still all bolt up fine (you have to stretch them), probably also a new dump made up (or modified) and the vct line tapped & a new timing belt..

I'm not sure but I'd say the existing rb20 sump should bolt upto the sump adapter, if not rb26 sumps are pretty cheap to come by and the diff can be transfered across :)

Just a thought really - In my mind it sounds a better option as the parts are alot easier to come by!

Anyway best of luck with it!

It's not that i don't have the money for a 32gt-r or 34GTT its just that i dont want them.

Blind Elk- Do you have any more info on the swap? Any pitfalls etc? Feel free to pm me or send the details through to greg.dekwant(at) gmail.com, I'd be grateful for any insight you could give me. Cheers.

The main pitfall is retaining ATTESSA. If you are going for an aftermarket ECU, get a PnP GT-R version.

Other than that, it is a simple bolt-in proposition.

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