RB20/SR20 5speed hybrid how to?

[Evocom]

Hi all. It looks like the sr/rb box in my SR ke70 track car is about to let go as it really doesn't like to go into 3rd any more:worried:. I have another RB20 box [complete] and am picking up a busted SR box with good housings and hope to mate the two in holy matrimony:wub:. I'm trying to build one so i can straight swap it over when i pull the other out.
As far as i can see it looks pretty staight forward but i thought I'd ask incase anyone has done such a swap and knows of any tricks/tips or hassles.
From what i see there is 5 bolts holding the clutch bearing carrier on inside the bell housing and 8 [i think] bolts holding the casings together in the middle of the box that come through from the back and thread into the front half of the casing. From what i've been told i just take the bearing carier out of the front [and possibly a circlip?] and split the box in the middle leaving the gearset and all on the rear housing and just fit the Sr front housing back in place of the RB unit that I remove.
Is it that simple??? sounds too good to be true.
Any help would be greatly appreciated:))

[Jonny Rochester]

Yes, you have the right idea. If the rear housing seperates from the sandwich plate also, you are best to take it right off to clean it up and get a good seal. Otherwise just stuff some silicon in the gap and hope for the best.

Clean all surfaces, then use silicon to seal it up again.

It's a good idea to get a new input shaft seal.

[biggo]

holy moley!!!

someone researched before asking a tech q????????

[Evocom]

Thanks guys. I'm gonna give it a crack tomorrow night. I was planning on putting new input and output shaft seals in it coz i cant be bothered puttin it all together to find out one or both are shagged. They aren't expensive anyways.

[steroidchickens]

thats correct.

but. what box have you got?

you already have an sr20 bellhousing on an rb20 gearbox?

and you are putting another rb20 box in so reusing the sr20 bellhousing?

if thats the story all will be fine.

unbolt. take off circlip. just be really careful when pulling them apart. i did it once when using a ca18 bell on rb box and bumped one of the carriers. knowing me drinking all night diddnt check the box selected gears properly put it in the car only to find out i had to pull it out again.

[Evocom]

i have a complete working RB box and a complete Sr box that has a snapped output shaft so Im only using the bell housing part.

[H8CHIR6KU]

just make sure the washer that will fall out when you take the front plate off, goes back in

[Evocom]

just make sure the washer that will fall out when you take the front plate off, goes back in

Is this a shim washer that sits between the front cover thing and the bearing for the shaft that runs next to the input shaft?

[Jonny Rochester]

It is a shim. In setting up the gearbox propperly, you are suposted to check clearances and choose the right size shim. And the gap maybe different with your different housings. But, most people just put the same shims back in and she'll be right.

[FAST EDDIE]

yer thats how easy it is as for shim its not important i had one worn out to a poofteinth and it still works fine, i also have a spare rb sr box sitting in my shed, oh and if u split that 2nd half of the box remmeber to slam some glue in it, i use winsdcreen urethane to seal everything on my car!!

[Evocom]

I ended up taking both casings off the RB box as i split the sr one today at work and threw it in our turbo wash and it came up sweet so i figured ill do both ends so it looks nice and then ill give it some good oil. thinkin redline shockproof. got new shaft seals and ill get a new front cover gasket and a shifter plate gasket. One thing i'm a bit suss on is what i believe is the reverse idler gear on the new [to me] rb box is a bix worn on the edge where it meshes so i might get it checked out but the rest of it looks sweet. i dropped the oil out of my other box and it was full of nice gold looking little shavings. its a shame the box doesn't want to come out of the car as easy as the new one came apart. oh well.

[Jonny Rochester]

The wear on the reverse idler is sort of normal. No syncro. Don't worry too much.

[Evocom]

Well i got the box out. was a lot easier with a little help from my housemate on the trolley jack. Once i got the box stripped i found a little difference. on the middle selector there is a spring loaded pin thing that goes to the selector fork and pushes off the center plate thing. the new box i have does not have this, i'm told its from a 32 where the old one is apparently a ceffy box. The gearset seems to be the same so i think it won't matter? anyone know if this will be a headf#@K? the wear on the idler gear was worse on the one that came out so she'll be right.