S15 Spec R w/ 5-spd (which driveshaft?)

[superbike81]

I'm running a S15 motor and S14 SR20DET 5-spd transmission on my S15. I just did the swap, but the driveshaft (which is complete from an S14 also) didn't fit right. It goes in, but it seems it's just a little too long, because I had to force it up and then force the center carrier to line up with the bolt holes.

It spins fine when going slowly, but after driving about 25-30mph for about 20 seconds, the shaft starts shuddering pretty violently until I stop the car. Then I can start again and the same problem happens in a few seconds. I'm not sure what's going on. Did I get the wrong driveshaft?

 

[elizium]

I had a problem with the driveshaft when I changed to a 5 speed... in the end I had a one piece made up and everything is now fine

 

[superbike81]

I was hoping that wouldn't be the case. There must be some way to use a 5-spd on an S15 motor without using a custom driveshaft. Right?

If that's the case, I'll just buy a 6-speed mission and install it.

 

[Matt_S]

Sounds like you need a manual one. There is approx 20mm float, so you can insert the PROPSHAFT (driveshafts go from the diff to the hubs :wack: ) and then pull it back to meet the centre bearing.
Other than that, see if its not knocking on the exhaust system. Had that before - had to shift the exhsust and it was fine.

 

[superbike81]

guess that's just the difference in English and American English.

We call it a driveshaft. The parts from the diff to the hubs are axles.

The part that I have is from a manual S14 turbo, so I'm not sure why it's not working.

 

[Matt_S]

I'm running a S15 motor and S14 SR20DET 5-spd transmission on my S15. I just did the swap, but the driveshaft (which is complete from an S14 also) didn't fit right. It goes in, but it seems it's just a little too long, because I had to force it up and then force the center carrier to line up with the bolt holes.

Err, you said you used the Auto parts? :wack:

Use the manual 'front half' of the 'driveshaft'

 

[superbike81]

I'm using a complete manual S14 SR20DET driveshaft (propshaft).

I attempted to bolt the front half of the S14 SR20DET driveshaft to the rear half of my stock auto driveshaft, but the bolt holes in the center don't line up.

 

[Matt_S]

Weird. In the UK you can bolt S14/SR front halfs to S13 (CA) rears for when you do S13 CA/SR swaps. Cant see it being different for JDM models. Were both models ABS (or not)? THe rear half of the prop is longer on the non ABS models. That 'may' be an issue. Ar eyou sure your bolting the centre bearing bracket up correctly? Bolted it up wrong (upside down) before on the S13 and didnt realise til I tried to drive it and it made a racket :wack: