Drive shaft shortening

Turn & Burn

Club Member
I plan to install a S15 helical lsd in my R200 diff but I need to also fit the diff stubshafts which are the 3x2 pattern. To do this I will need to shorten the existing driveshafts by approx 35mm.
The easy and expensive option is custom drive shafts incl a change to cv’s.
The cheap option is to make an adapter to mount the existing yokes to the new 3x2 flange and shorten the spline on the driveshaft by 30mm or so. As all the drive shaft balls and spacers remain in place and the sleeve yoke remains full length I reckon this will work.

Has anyone tried shortening and was it successful?

upload_2018-4-23_21-9-56.jpeg
 
Last edited:

johnymd

Club Member
I have no experience with this but how about shortening at the position indicated with "1"? Cut and re-weld maybe.

How much power will you be running with the RB25? I'm guessing similar to a hi tuned L-series so in theory UJ shafts will cope. I'll be interested to see where this goes as I may need to address driveshafts on my 3UZ red car. I took it for a drive over the weekend and have vibration issues which is probable prop/drive shaft related.
 

Mr.F

Inactive
I think area 1 is the only place to do it - cut and sleeve for strength and alignment? Make sure UJs stay aligned too.
 

jonbills

Membership Secretary
Site Administrator
Why have the pain of this? Is the s15 helical much better or cheaper than a Quaife?
 

PeterAllen

Well-Known Forum User
I've shortened driveshafts successfully - and my Zed has 350hp.

You need to turn one end of the cut shaft down to create a spigot and drill a corresponding hole the cut portion of the shaft. This will aid concentricity when joined. Machine a chamfer from the OD to the spigot/hole. Then mate them together and fill weld the 'Vee' whilst the shaft is rotated. Special welding rods are required (seek technical advice) as you will be destroying the heat treating and case-hardening of the OEM component. No sleeving is required but it doesn't hurt. However, is a sleeve likely to create a MOT issue over there?

If you find someone who utitises this technique you will be okay. Don't just get a mate of your sister's girlfriend's ex-boyfriend to weld it.
 

Turn & Burn

Club Member
I spoke to a driveshaft company who recommended cutting and friction welding as means of shortening and said they do it fairly frequently on cv type driveshafts. The issue with the Z is the UJ which is bigger than the lathe chuck so they couldn’t accurately grip that end of the shaft.
I have tried shortening shafts by cutting, keying and sleeving on a 250bhp Westfield but it was only briefly successful!
 
Top