View Full Version : Using GTS-4 RB20 for RWD s14 swap.

02-05-2012, 02:09 AM
So starting from the top, my s14 KA spun a bearing at the track last weekend so I need something cheap and done quickly. Need to have it done in a months time before spring break to go back home. I would rebuild the KA, but for the price I found a FULL R32 GTS-4 front clip. Transmission included, but no driveshaft (DS).

Now, Ive done research and an RB20DET is a doable swap, but I have not been able to find info on what RB20 people used. Most of the time it sounds like the RWD RB20 and they were able to keep their DS and used a conversion mount kit or the R32 Crossmember.

My question is, what needs to get done to the AWD RB20DET to be able to use it in a RWD 240. So far I've come up with swapping oil pans to get rid of the t-case and front output shafts. But how bout the trans? Will the AWD trans still be able to be used with the S14 DS? Or will it need a custom DS?

This is more out of curiosity (extrememly unlikely to actually happen) what would it take to keep the AWD functioning? I know theres the RB26 R14, and ive seen the info thread for the RB20 AWD 13, but I wonder what it would take into a 14.

And lastly what are some in general heads up for the RB20 swap? The downpipe/elbow doesnt clear, so Ill need a new one. Ill have the crossmember so I have that covered, Ill have ECU, and cluster to be able to keep tach, and I found the wiring pin outs for the RB20 to s14 also.
*EDIT: Just thought of another thing Ill probably need : a fuel pump. Random stuff like that, is what Ill forget and just asking to gather a list.

Thanks for the help in advance!

02-05-2012, 02:17 AM
Basically the same thing you do with an RB26 swap. You'd need a RWD oil pan so you can get rid of the transfer case and you'd need an RB20 RWD transmission...

02-05-2012, 03:35 AM
Ok, thats what I was afraid of. RB20 trans (and parts in general) are hard to find, as im figuring out. Would a more common RB25 trans bolt up? Yes I know its more $$.

Also, I read that both KA and RWD RB20 trans are FS5W71C, could I use my KA trans and the AWD RB20 bell housing switched over? Or does the AWD bell housing not bolt up to the RWD main trans?

EDIT: It was late, shouldnt have posted haha. Yes the RB25 trans can bolt on to a RB 20 but it is not worth it budget wise, im back to what it costs rebuilding a KA.

Now, Ive read mixed things about swapping bell housings so thats still unclear, some people say yes, others say no. Most are from 3+ years ago. Any insight on something more recent?

And how about just using the AWD trans with the switched oil pan, shouldnt that work also?

02-05-2012, 11:29 PM
After more searching, the AWD trans can NOT be used without the t-case. If I left the t-case in there and cut the output shafts it would work but sacrifice weight. Not worth it.
(pretty much what fliprayzin240sx said)

So the only options are finding a RWD RB20 trans, or figuring out if the KA transmission fits into the RB20, which I still continue finding conflicting results.

02-07-2012, 05:45 AM
I could have sworn that RB20 bellhousing is almost the same pattern as a KA bell housing. You might be able to get away with using the KA transmission.

02-07-2012, 07:04 AM
for real?

Let me google that for you (http://lmgtfy.com/?q=can+i+use+a+ka24de+tranny+on+rb20%3F)

its the first thread

02-07-2012, 08:50 AM
^^^^ hahahah thats tooo funny.

Promise Land
02-07-2012, 12:40 PM
How does an RB20 swap with all this research come out as "cheap and quick within a month's time"? The project sounds great. Not sure it's all worth it when you could rebuild your KA with forged internals for more abuse at the track.

02-07-2012, 12:42 PM
you can swap the bell housings so all you really need to find is an rb bell housing and you can run ka, sr, ca, rb trans behind it.

02-07-2012, 02:28 PM
i love my rb20 i recomened it. its a cheaper way then a rb25 but ur right about tryn to find parts it sucks this forum is my only way lol but once u get it figured out im sure u will love it. best of luck to u. and if u need any pics my motor and trans is currently out im building it so let me know. good luck

02-07-2012, 02:46 PM
Yes a RWD transmission from an RB20 will swap bellhousings with a KA transmission. The AWD bellhousing will not. So pretty much I'd need to buy a RB20 bellhousing (which Im not going to find) or the whole transmission which puts me above my budget again. I talked to RawBrokerage and a buddy who has an RB25 to get some insight. Pretty much, the only thing you can use out of a GTS-4 is the motor. The crossmember is different so it wont just bolt up like a GTS-t. The ECU goes haywire as soon as it looses AWD, so I'd have to get another ECU. If it wouldve been a GTS-t front clip, it wouldve been perfect, but oh well. Skyline GTS-4 Front Clip (http://santamaria.craigslist.org/pts/2798440264.html)

I could rebuild the internals of the KA, but it adds up really quick. I had already pieced together a "shopping kart" to see approximate pricing. Sure eagle rods and some wiesco pistons with ACL bearings are only 1k. But then theres machining, gaskets, timing chain kit, etc, and all the small things add up. When I first saw the c-list it made sense to go with that. Right now Im back to square 1.

02-08-2012, 09:26 AM
Id say search on here for somebody selling a rb25 swap. a little more cash but def best bet. very good bang for the buck if your going to swap a rb

02-08-2012, 09:38 AM
Id say search on here for somebody selling a rb25 swap. a little more cash but def best bet. very good bang for the buck if your going to swap a rb

^^^ or just get a dam sr20det. It would pull a premium before street wars. ha