Jump to content
SAU Community

Recommended Posts

Hi, i was wanting to know how much the RB20DET box can handle? i now it would be best to get the RB25det box, but at a third of the price its hard not to consider the RB20det box. my car is a relatively stock (for now) R33, my goal is one day to have round the 250-280rwkw mark, with track days etc in mind. will it be fine with just a better clutch or what?

Cheers

Link to comment
https://www.sau.com.au/forums/topic/352978-rb20det-box-on-rb25det/
Share on other sites

RB20DET is a piss weak gearbox. I wouldn't put one in a stock RB25 street car, let alone tracking @ 250rwkw.

Also, FYI an uprated clutch puts extra pressure on the gearbox, not the other way around. It's meant to be the weak link in the driveline. What's wrong with your current gearbox?

also depends alot on how you treat your car/box.

i have a 20box running behind a 30DET with 285rwkw and a bucket load of torque. its a track only car too, been going good for two years doing motorkhana's, texis, hillclimbs and normal track days.

i figured i could go through 5 for the price of one 25box, but yeah, so far so good.

Yes, you would have to reconvert everything as the RB25 is a completely different box. Do it properly first time around and get an RB25...there's a reason Nissan didn't use the RB20 box in the R33. If you blow up even one or two boxes, the cost and time to replace won't have been worth it, not to mention how bad it feels retiring from the track with no gears :)

not to mention how bad it feels retiring from the track with no gears :)

you'd have to feel awesome but, like my car is sooo powerful it munches metal cogey spinney things!

Really is a valid point though.

you'd have to feel awesome but, like my car is sooo powerful it munches metal cogey spinney things!

Really is a valid point though.

Hahaha, or the sad reality in most cases "I can't drive a manual for shit".

I'm very surprised you've lasted this long with the RB20 behind an RB30ET. Very lucky or you know how to take care of it I'd say. There are that many people who blow up the RB20 box with little more than factory boost. How much does your R31 weigh in race spec? Might factor into things, as you can run piss weak boxes behind lightweight Cobra kit cars with big V8s all day long and have no issues at all.

I also had a couple of years with a 20 box behind a 280odd rwkw rb25. Ended up removing it and selling it to upgrade to a 25 box before the inevitable death and zero resale.

This was in a full weight 32gtst.

It did get a little noiser over that time but still shifted fine.

Mechanical sympathy and a sprung centre clutch is the key.

Hahaha, or the sad reality in most cases "I can't drive a manual for shit".

I'm very surprised you've lasted this long with the RB20 behind an RB30ET. Very lucky or you know how to take care of it I'd say. There are that many people who blow up the RB20 box with little more than factory boost. How much does your R31 weigh in race spec? Might factor into things, as you can run piss weak boxes behind lightweight Cobra kit cars with big V8s all day long and have no issues at all.

just lucky i'd say. i break stuff alot.

when i last weighed it, it was 1150kg dry. so +100kg for me, say 40-60kg for cage and 35kg in fuel.

maybe 1300-1350kg

tyres are 235 fedi RSRs and a sprung centre 5 puk with 4000 pound clamp load & carbonic? pads. maybe combination of lighter weight, smaller tyre contact patch and clutch help

i actually dont want to break the box, i got a case of piss saying it'll last 12 outings.:rolleyes:

I have a rb20 (nics) if it makes a difference behind my rb25 in my coupe! Car makes around 180rwkw not to sure but im having it dynod friday! Has lasted about 2 months now. But i don't drop the clutch on it hard etc, but i think it comes down to the clutch too! I have a heavy duty clutch in it from when i bought it but i need a new clutch so if i went a too harsh clutch it would probally break after a while..

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Pads for R32 GTS-t, R32 GT-R non V-Spec (Sumitomo), R33 GTS-t and R34 GT-t are all interchangeable. R34 GT uses a 2x piston caliper, hence it didn't fit.
    • Checked with amayama and nope, the full S2 manual set is not available anymore. Unsurprising, but still disappointing as the ? on availability gave a glimmer of hope.
    • I've heard the Tomei USA head gaskets are decent if you want to o-ring the heads but otherwise not recommended.
    • The 296mm rotors are the R33 turbo brakes. The 310mm rotors are the R34 turbo brakes. The calipers are nearly the same, but not. They're the same caliper but the R34 caliper has longer legs so that it sits out far enough to go over the rotor. The pads are the same for both. When you say, "I bough tsome EBC"....did you just mean pads? Or rotors? 310mm rotors fit under 17" wheels. There may be some wheels without enough clearance though. I can't fit my fingers between the barrel of my wheel and the "corners" of my R34 calipers, but there is plenty of room behind the spokes. This is on Enkei RPF1. You can fit 324mm rotors inside a 17" wheel, but I'd be willing to bet that it would be close to impossible with the Nissan/Sumitomo caliper (using an adapter, of course), because the Sumitomo caliper is fatter than the Brembo caliper that is supposed to go on the 324mm rotors.
    • Hi. Can someone tell me what brakes(and mainly WHERE) can i buy brakes on R34 GTT? I bought some EBC which SHOULD go on my car(i have GT but it has GTT brakes) but it does not fit, Brakes are "too" small(296mm) Are 310mm be good or? I have 17 inch wheel so no "big boys" but for me driving i just need one that fits and i can get here in EU/Czech.
×
×
  • Create New...