240 SX/S15 Transmission Question (its from way out in right field)

[RAD2LTR]

I have a 69 Datsun 2000 roadster and I keep blowing up 5th gears. Nissan released a TSB back in the 70s about it. The problem is that the fix aparently doesn't last that long. My question is: Will a s15 6spd mate up to a KA? If so can the bell housing be swapped to a Maxima Diesel bell housing form the early 80s? I'm guessing the answer is no, and no. The reason I ask is that there is a rumor that a KA transmission can be mated to the Maxima bellhousing that will bolt up to my U20 with the starter on the correct side. I'd need to change the throw out bearing, build a driveshaft, and rig up a transmission mount

The cost of repeated gearbox rebuilds is adding up ($1200 each time) and I only get about 10000 miles out of a 5th gear. If I could find a way to get the 6spd to work, I'd have the only 6spd Datsun roadster out there (without an engine swap). Before anyone says just do a swap, I make more hp than an SR anyway. I'm not about to even think about cutting anything as it will perminantly ruin the car.

Thanks,Will

[Bwana]

Wow, that's an interesting problem you have there... The info you need may be out there, but I hardly know where to start searching for it. Would a 5 speed swap using a KA/SR/CA trans be an option for you? It would for sure be a lot cheaper.

[RAD2LTR]

It would be nice to have a 6spd in the car. Doing an engine swap is absolutely out of the question. I HATE seeing roadsters with the wrong type of engine. Its like swapping a SBC (small block chevy) into a 250 GT California Ferrari. The roadster 5spd is an awesome box, aside from the 5th gear issue. Its the smoothest shifting transmission I have ever felt. The reason I'd like a 6spd is that I run a 4.11:1 rear end, and on the freeway I turn between 4 and 5K rpm in 5th currently. I need the close ratios for track time, but getting to and from the track is a different story.

Will

[LayNLow240]

as far as i know, a sr20det trans will bolt up to a ka with a bell housing swap. i am not too terribly knowledgeable about s15's though, but im pretty sure they are the same as the other trans as far as the bell housings go.but one problem would be, the s15 doesnt have the speed sensor in the trans itself.if i am wrong, feel free to correct me.

[Bwana]

Weather the bellhousings interchange or not is going to be dependent on the case of the 6 speed, it may have a different case to bell bolt pattern. I'm still looking for info on that...

[LayNLow240]

i say that because i hear about people in japan changing out their 6speed for a 5 speed because they claim the trans is weaker than the 5 speed.so if an earlier sr trans will bolt up to the s15, then that means the bellhousings are the same. but if they swap the back halves then it will mean the case pattern is the same.

[yokota180sx]

as far as i know, a sr20det trans will bolt up to a ka with a bell housing swap. i am not too terribly knowledgeable about s15's though, but im pretty sure they are the same as the other trans as far as the bell housings go.but one problem would be, the s15 doesnt have the speed sensor in the trans itself.if i am wrong, feel free to correct me.

yes yoru right

s15 transmission on ka bellhousing