Part 2, Gearboxes:
There are two main types of gearboxes for use on RB engines. I haven't inlcuded the 4WD Skyline GTR gearbox, due to the fact that most people who want a RB engine in their S13 don't want to go to the trouble of installing the 4WD system.....
Nissan FS5/MF5:
This is the stock gearbox that comes with the RB20 engines and the non turbo RB30 engines. The MF5 has single ring syncros while the FS5 has twin ring syncros on 2nd and 3rd gear, which means they take a bit more punishment, before they cry "enough!"
Compared to the larger MX7/R33 skyline gearboxes these are very weak units, however they will survive upwards of 220RWKW without too much trouble. The main problem people have with these gearboxes is when you start adding ceramic clutches. DON'T USE CERAMIC CLUTCHES ON RB20 GEARBOXES!!!!!!!!! Have I got my point across?
As with all Nissan gearboxes, they share a common design fault of the output shaft bolt comeing loose, allowing 5th gear to get destroyed. So If your going to put one of these boxes in you car I'd suggest you pull the rear houseing off and tighten up this bolt....not too hard really.....
Also these boxes dont have a syncro on reverse gear, so don't go jamming them into reverse while your still moveing forwards..please! I've seen a FS5 gearbox with the layshaft completely snapped off becasue the owner did this...well he selected reverse instead of 4th at 6500rpm but still!
Nissan MX7/R33 GTS-T:
Same as before, The MX7 is has single ring syncros, and the R33 box' has twin ring units. Only this time the R33 has twin ring units on everything! these boxes are built like a brick s**thouse (aussie term) and take a heap of abuse.
And yes you can use a ceramic clutch on these puppies...happy?
Also as before 5th gear dies due to the output shaft and layshaft nuts, do 'em up!
Another thing, is these boxes are much larger compared to the the MF5/FS5 gearboxes. So if you install one in your S13/240' you may have to "massage" your trans tunnel with a hammer (I know it sound grusome) to get it to fit. Also they run a diffrent starter motor and flywheel (flywheel is much larger, thats for the bigger clutch!).
You will also require a diffrent, larger gearbox crossmember. You have been warned....
This shows the size diffrence between the MX7/R33 box and the FS5/MF5 gearbox. Image provided from Kneedrager from the Calaisturbo fourms
Jatco Automatics:
Yes a auto. Only loosers drive autos? Rite? WRONG! Remeber automatics when they change gears keep the engine on boost. You may loose 10RWKW on your dyno sheet with a auto but you have a faster 400m time....
If your going to have a huge motor infront of your auto I'd suggest a large transmission cooler, try and source one off a large domestic American V8 with a automatic trans.
Also I'd recomend, a 2500rpm Hi stall torque converter, and a manual valve body. The valve body is optional, but with a high stall expect to drop some time off your 400m passes. If you really wanted to be insane, you could go with a 5000rpm histall and launch your front wheels...hmmmm
Othermods, include uprated internal clutches and friction lineings, larger drive pistons and servos (2nd gear), and your input and intermediate shaft upgraded, either by heat treatment, or replaced by hi tensile units....by this time you'll have no trouble running over 500RWKW through one of these gearboxes....
Nissan automatic gearboxes have a diffrent tailhaft yoke compared to the manual gearboxes, so you'll need a diffrent tailshaft if you want to go auto!