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ok i have a 89 gts4 rb20det awd with gtr g/box & diff. i want to convert it to a rwd. i have the switch but i dont like the extra weight from the front diff & transfer.

so can i get a rwd sump and bolt that to my rb20. then drop the transfer and front shaft and get a rear drivershaft made up to fit, or do i need a rwd engine, box and diff?

also how much work is needed to fit a rb25 into the r32?

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By the way. I'm putting a 25DETNeo into my R32 and it is costing me thousands. The motor and gearbox set you back ~$3k, then there's all the sensible work to do (like timing belts, coolant hoses, and so on) and wiring changes and air con hose changes and power steering hose changes and tailshaft surgery. It all adds up, even if you do a lot of it yourself - you still need to buy or otherwise obtain a bunch of bits and pieces.

cheers

ok i have a 89 gts4 rb20det awd with gtr g/box & diff. i want to convert it to a rwd. i have the switch but i dont like the extra weight from the front diff & transfer.

so can i get a rwd sump and bolt that to my rb20. then drop the transfer and front shaft and get a rear drivershaft made up to fit, or do i need a rwd engine, box and diff?

also how much work is needed to fit a rb25 into the r32?

No, the block is a different shape because of the diff/sump, you will need a RWD block. Its going to be better and cheaper for you to buy a RB25.

block is not different. yes you can fit a RWD sump.

you can buy a RWD RB20 box and then RWD RB20 tailshaft and that should all fit fine. otherwise you can leave the transfer case there but cut the side off it and just keep your standard tailshaft (but it means sacrificing your transfer case and a bit of extra weight).

if you go this way, sell me your front GTS4 diff/pinion. I need a spare. :)

you cannot just remove the transfer case as the output from the gearbox is made to go into the transfer not to bolt onto a shaft. so that's why you need to keep the transfer but with the front drive bit cut off and the guts out of it. or just get a RWD box (it has the right output shaft).

Don't forget that if you don't have a front diff, then you don't have front driveshafts. If you don't have front driveshafts, you don't have axles for the front wheels / hubs.

Sell the GTS4, buy a GTSt if you only want RWD. Don't go destroying a perfectly good car because you made the wrong choice of car in the first place.

block is not different. yes you can fit a RWD sump.

you can buy a RWD RB20 box and then RWD RB20 tailshaft and that should all fit fine. otherwise you can leave the transfer case there but cut the side off it and just keep your standard tailshaft (but it means sacrificing your transfer case and a bit of extra weight).

if you go this way, sell me your front GTS4 diff/pinion. I need a spare. :)

you cannot just remove the transfer case as the output from the gearbox is made to go into the transfer not to bolt onto a shaft. so that's why you need to keep the transfer but with the front drive bit cut off and the guts out of it. or just get a RWD box (it has the right output shaft).

Is there a difference in the design of the r32 and r33/r34 blocks? I know i could not align my 4WD sump onto a near new r33 RWD block as they were a different shape to the 4WD block. When i rebuilt my engine i had to bore the old block out 40 thou to compensate, ended up better anyway.

EDIT: maahhh bad O.P., i thought you were wanting to keep it 4WD =/

Edited by central coast person

yeah i also realised the front cv's/axles after i posted. im not going to bother with changing it, car is quite quick for a stocker just going to keep working on it. ive got a 5 puk exedy and rear main just need the flywheel. then fmic, nistune, and carbon fibre boot then upgrade turbo and exhaust. :D thinking a hks 2530 and 5zigen 3' exhaust with no cannon.

Edited by drop2nd
  • 2 weeks later...

I've just converted my R32 GTS4 to RWD, not because I wanted to tho... I stacked my GTSt and bought a GTS4 to replace it, I could only find an auto one tho.

The engine became smokey shortly after buying it so I swapped in the engine out of the GTSt into it with a R33 GTR gearbox to convert it to manual.

Cos the blocks are different and it's my daily driver I didn't have time to adapt the 4WD sump on the GTSt engine.

The RWD engine bolts up to the 4WD box no worries, and I just disassembled the front CVs and fitted the stub axles in the hubs.

If you're worried about the extra weight of the transfer case I saw a gutted transfer case on ebay earlier today.

Good advantage of keeping the 4WD box is its much stronger and half the price to replace as an r33 gtst box.

Comparing the GTS4 to the GTSt, there is a fair bit more beef in the front and rear K frames, and they hang lower in the GTS4.

Convert or replace, its prob as much trouble either way?

just going to keep the gts4, possibly getting a rb25neo awd motor from a stag :D if not just going to trick it out with the garret version of the 2530, 6boost manifold, 5zigen 3' zorst, return flow fmic, nistune and a tune, c/f boot and some drifteks. meanwhile get a s13 and start building a drift machine.

anyone else with soem conversion stories?

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