Alternate 5th Gear

[90RS13]

http://www.nismoparts.com/catalog/?section=241

I didn't know how many people know about this, and I searched and didn't see any posts on it.

[projectRDM]

It's from the SR transmission. Direct drop in, but it'd be easier and cheaper to buy a used SR transmission and swap bellhousings then to buy that and rebuild your existing one.

[deviousKA]

That alternate 5th for the 240sx tranny is actually from the d21 truck transmission (although, some could argue its from sr tranny, its the same part anyways). 86-97+ d21 hardbody transmission has it, the complete transmission can be swapped in 240sx and can be had rather cheap. 1-4 ratios are identical.

There are many more tranny gear ratio options (and other transmission manufactures as well). 240sx 1-4 ratios are ok, but close ratio is a must to keep the engine in power band with high rpm. 240sx uses a C-type nissan transmission, with limited aftermarket gear ratio options. Swapping to a B-type opens up many options (nismo road race, rally, close/wide ratio sets, etc..). Borg Warner t-5 swap is another option, offers much closer ratio sets and tons of aftermarket. This requires custom driveshaft or different engine placement.

That bit of info is probably overkill for this reply, but i thought id throw it in for good measure.