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Gtr Box Converted To Rwd

boostn32
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boostn32 Mentor

boostn32

Posted
Posted (edited)

Ive heard a few people converting a GTR box to rwd, how hard is it? the welding wont be a problem, but not sure whats

involved with the guts of the transfer case, also will a 20 clutch fit or is the gtr box input shaft bigger? Thanks Luke

Edited by boostn32
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R31Nismoid Grand Master

R31Nismoid

Posted
Posted

Shop around, i paid $1300 for mine with a tailshaft/yoke etc.

GTR gearboxes go for around what, $1100 and its time and effort.

Not to mention depending on the previous life - you could be easily breaking 3rd gear as well.

I'd never go near a GTR box in RWD TBH.

Rolls Grand Master

Rolls

Posted
Posted (edited)
you gave no reason and for that i see no reason

They have a harder life and shred 3rd gear a lot, for only saving $200 you have to modify the box quite a lot and then run the risk of it being in far worse condition than the 2wd box. Not worth it for a $200 saving.

This is essentially what nismoid said.

Edited by Rolls
Roy Grand Master

Roy

Posted
Posted

But it is a good question. R32 GTR gearboxes can be had for as little as $500 (Yes I know, what is the condition)

But the reason I am interested is it opens up a world of possibilities for me :) I would love to buy a GTR box that is for sale at the moment that has a full OS Giken close ratio 5 spd gear set in it. Throwing a GTR box in my R32 GTSt also means that I could probably use a botl in R32 carbon propshaft with the GTR rear cradle I have to install in the car.

So, if someone knows whats involved then I am interested, because it means I can do some cool stuff to my drivetrain that will actually make my car quicker, not just more reliable as is the case with the RB25 box. It is more appealing to mod a gbox housing then get custom length carbon propshaft and buy the OS Giken gearset new and install it....

boostn32 Mentor

boostn32

Posted
  • Author
Posted (edited)
But it is a good question. R32 GTR gearboxes can be had for as little as $500 (Yes I know, what is the condition)

But the reason I am interested is it opens up a world of possibilities for me :) I would love to buy a GTR box that is for sale at the moment that has a full OS Giken close ratio 5 spd gear set in it. Throwing a GTR box in my R32 GTSt also means that I could probably use a botl in R32 carbon propshaft with the GTR rear cradle I have to install in the car.

So, if someone knows whats involved then I am interested, because it means I can do some cool stuff to my drivetrain that will actually make my car quicker, not just more reliable as is the case with the RB25 box. It is more appealing to mod a gbox housing then get custom length carbon propshaft and buy the OS Giken gearset new and install it....

Glad someone's not arrogant. it was a simple question, maybe to simple for some.

and to add i have found a gtr box that has been converted and had new syncros, and also another gtr box with tailshaft for less than 1k.

for those that say they would never touch one i would rather listen to some one that knows a bit more. There advice its a better option than a 25 box and proven.

Edited by boostn32
The Dan Grand Master

The Dan

Posted
Posted

It's not a better option and there is no way they can prove that it is.....basically, an RB26DETT gearbox is an RB25DET gearbox with a transfer case on the back. Not only do you have more weight hanging off the back due to the Attessa clutch drum, but you have also got to factor in the cost of modifying your tailshaft as the GTR one is different.

The clutches are the same as long as you get an R32 GTR gearbox pre 07/91 and it's a push type. They are all the same....RB20, 25, 26 etc.

There is no strength gain from going to RB26 gearbox as the internals are identical to RB25.

I just find it awkward that you would want to hack apart a GTR gearbox when it will cost roughly the same to buy an RB25 one that will go straight in, will be as strong, and will not have as much rotational mass to turn as the butchered GTR one.

On the subject of why a GTR box is not going to be as strong....that is only true for second hand ones that have not been rebuilt. Because more torque and more revs are usually put through them, 2nd, 3rd and 5th synchros cop a punishment...but that goes the same mostly for the RB25 ones getting around. As soon as ppl stop paying $1500+ for f**ked RB25 boxes, then the prices will start coming down to 'fair' levels.

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

Arrogant? Oh please.

If you want to throw around words. - I think you are being rather ignorant of the situation & realistic costs.

The "best" of the GTR 5-speed is the R33 SIII (S3) GTR box. Same box you require if you want to fit a OS gearset for instance.

Series 1&2 boxes need additional parts to be purchased as part of the gearset install.

So clearly here there is a difference, and S3 boxes sell for what i said above. By all means gamble your money on a cheaper box, however check with your local casino what the odd's are for betting on black before you do so.

Proximity Motorsport Experienced

Proximity Motorsport

Posted
Posted

hey,

I am currently half way through doing two of these conversions. Im doing the first one becasue my mate had a GTR he crashed and we are putting the motor and box into his s13. And the other one Im doing because I know how easy it is, and I had a rb25 in my r32 with a rb20 gearbox, so I got a RB26 box for $600 delivered to nth qld from adelaide.

Basically if you blow a box you can just pull off the rear housing and bolt it onto a new rb26 box. I pulled all the clutch packs off it and gutted the silent chain and angle grinded the transfer case off it. Keep an eye on my build thread in the projects and overhauls topic. I havent finished even the initial post in there but once I do I will post up pics of the modded transfer case.

I think its a great idea if you have a rb26 box laying around. They can be had for so cheap

boostn32 Mentor

boostn32

Posted
  • Author
Posted
Arrogant? Oh please.

If you want to throw around words. - I think you are being rather ignorant of the situation & realistic costs.

The "best" of the GTR 5-speed is the R33 SIII (S3) GTR box. Same box you require if you want to fit a OS gearset for instance.

Series 1&2 boxes need additional parts to be purchased as part of the gearset install.

So clearly here there is a difference, and S3 boxes sell for what i said above. By all means gamble your money on a cheaper box, however check with your local casino what the odd's are for betting on black before you do so.

now thats all worth adding to this post, and i will take it all on board as its usefull information, yes i understand where your comming from now.

choku_dori i will keep an eye on your box transfermation...

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