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Advantages Of Double Synchromesh Gearbox?

jhjones
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GTSBoy Grand Master

GTSBoy

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I mean if you slam a fast gear change through with single synchros and get a crunch because you've managed to get the gear teeth to touch each other before the synchros have managed to match the speeds, then doing so on a double synchro will be harder. They also are "stronger" in that they will take such abuse for longer before wearing out.

cheers

GTSBoy Grand Master

GTSBoy

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Posted (edited)

Don't try to run an RB20XXX box behind an RB25DET. The RB20DET box is essentially the same thing as the RB25DE. Pretty strong, but not able to handle the torque from a 25 turbo for too long. The RB25DET box is a big heavy bastard of a thing for a reason.

But looking at your other thread, you're asking if you can put a 25DET box behind an RB20E? Well, if that's the way you were asking in this thread too, then yes, it will fit up to the motor, but I don't know if the length is the same. You might need to find the mathcing front part of the tailshaft to go with it.

Edited by GTSBoy
jhjones Rising Star

jhjones

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Posted (edited)

Don't try to run an RB20XXX box behind an RB25DET. The RB20DET box is essentially the same thing as the RB25DE. Pretty strong, but not able to handle the torque from a 25 turbo for too long. The RB25DET box is a big heavy bastard of a thing for a reason.

But looking at your other thread, you're asking if you can put a 25DET box behind an RB20E? Well, if that's the way you were asking in this thread too, then yes, it will fit up to the motor, but I don't know if the length is the same. You might need to find the mathcing front part of the tailshaft to go with it.

What I mean is will a 25det box fit in a 20e chassis without modifying stuff. Anyway I get it now.

Another is, is the clutch and flywheel different sizes?

I dont beleive they are stronger, imho its just smoother transition into gears

Can anyone else confirm this?

Edited by H4x
wlspn Proficient

wlspn

Posted
Posted

What I mean is will a 25det box fit in a 20e chassis without modifying stuff. Anyway I get it now.

So your R33 currently has a RB20DE gearbox?

You should be able to fit an RB25DET box but may need to modify gearbox cross-member (very easy, ask via PM if unsure how) & would probably need to modify tailshaft for the bigger yoke needed for an RB25DET box.

Another is, is the clutch and flywheel different sizes?

Clutch & flywheel will be identical.

Can anyone else confirm this?

Yes, that's right. Although as the box will cope better with harsh shifts, etc it will seem stronger...

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