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Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Thu Aug 15, 2013 12:31 pm
by rgh0
The information on the drive shaft lengths was posted a while ago, as I remember I contributed the lengths I used for my Elan and Plus 2. I had a quick look but could not find it and have to get up at 4 am tomorrow so I will leave it for someone else to find now :D

cheers
Rohan

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Thu Aug 15, 2013 12:32 pm
by miked
Chris,

If you are talking about the total length of the drive devices, I have them.

S4 Elan = 310 mm long
Elan Plus = 386 mm long

These were taken from cars at unladen ride height (on their wheels). On my back with a tape! These are the measurements from the faces of the diff output (3 ear) to the hub shaft shaft (3 ear). I have no doubt there will be some differences over various cars with chassis and bone dims.

Mike :)

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Thu Aug 15, 2013 12:36 pm
by miked
Chris,

I take it that you know the benefit of short stroke rear damper inserts to limit the droop and acute drive gear angles. TTR does them. Mike

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Thu Aug 15, 2013 5:23 pm
by AHM
Depending on the CV joints you are using they are right on the limit of articulation at full droop.

The length of the shaft depends slightly on the thickness of the adapter. with 13mm adapter plates I have a 300mm shaft - it pays to have a trial fit.

recent discussion
lotus-gearbox-f37/rotoflex-not-rotoflex-t26435.html

Details for adapter and Rohan's very useful input
elan-mods-f31/elanmac-conversion-t24920.html

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Thu Aug 15, 2013 6:38 pm
by Chris
Thanks for the info John.

Just what I needed, at least I can continue to use my car whilst I do the shafts.
Thanks again.
Chris.

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Thu Aug 15, 2013 9:12 pm
by Chris
Hi Vernon.

When I get the splined shafts made and fitted, I will try to provide some photos with explanatory write up, it may be of use to someone. I made adaptor plates were made from steel, the reason for this was I didn't like the idea of my car being propelled by six 8mm bolts screwed into aluminium, and also I had the steel shaft to hand.
Cost wise so far 4 core plugs ?8.99, Counter bore cutter ?10.73, 12 splined studs ?17.00, 4 Stahltec 100mm cv joints complete with boots, bolts, gaskets, grease, circlips, and a two year warranty ?79.87 for the four. Total so far is ?116.59. I estimate the splined shafts will cost around ?20.00, and protective plating on the adaptor plates ?35.00 inc vat. Grand total ?171.59. Much better than ?600.00. The only machines required so far has been a lathe and a pedestal drill.
Best wishes
Chris

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Mon Aug 19, 2013 9:03 pm
by Chris
Hi Mike.
Sorry for the delay in acknowledging your advice regarding short stroke dampers, and also the total shaft lengths. I intend to take a look at my dampers, if they are leaking, or not working properly I will fit short stroke units. If they are ok, I will investigate shortening of the centre rod, and re threading to effectively shorten the stroke and hence the droop in case of any angular locking.
Blue Skies
Chris

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Mon Aug 19, 2013 11:06 pm
by billwill
Shortening an existing damper will in my opinion be a rather difficult job. Thats a bar of toughened steel in there about an inch in diameter. You would have to dismantle it completely and do the work on a big lathe.

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Tue Aug 20, 2013 6:01 am
by john.p.clegg
Chris and John

Seeing as both of you have +2s I dont think you will need reduced damper travel...

John :wink:

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Tue Aug 20, 2013 10:09 am
by miked
John,

When I made the suggestion about the short stoke dampers I had the Elan more in mind (than the Plus 2) but judging by the instructions that I was given about fitting CV's to a Plus 2 (with less droop), I was told not to let CV joints droop at all. They would be damaged. I could not accept this so stuck with sliding spline UJ joints. I continue to have no problems with them. Just my opinion that getting rid of excess droop is a good thing given the option of worn out dampers.

Chris, Good luck with your CV's. Having talked with manufacturers they all seem nervous about quoting actual maximum working angles of droop. Nice to see some finished photo's.

Mike :)

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Tue Aug 20, 2013 11:44 am
by john.p.clegg
Mike

Have you a "baby" as well as a Plus2 ?...

John :wink:

P.S.

" Just my opinion that getting rid of excess droop is a good thing given the option of worn out dampers.".....I'm sure Colin put the springs and dampers at each corner for some reason?...He was not a man to waste metal... :lol:

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Tue Aug 20, 2013 7:42 pm
by miked
John,

Yes, ongoing project car S4 FHC, nearly ready. Hope to try some hill climbs.

Re: Colin and wasting the metal, very true. Just following what the race boys are doing as lots have had droop limiters with straps before the short shocker came out. It seems logical although I don't know enough technically to say more.

Mike :D

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Sat Nov 02, 2013 6:42 pm
by Chris
DSC_0766.jpg and
Hi everyone. I have submitted a pair of photos of my homemade drive shafts, as requested. They started life as VW Passat shafts, and were cut to length then the cut end was splined and grooved to accept the new CV joints and circlips.
I assembled them on a rough and ready jig to represent the car. I have lost track of the total cost, but somewhere around ?200.00.
Chris

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Sat Nov 02, 2013 7:16 pm
by KevJ+2
Chris, fantastic job! I'm sure if you were to sell them at an identical price to 4 rotoflexes & bolts,
you would sell them easily. I for sure would give you an order as it's a job I have to do. Kevin.

Re: Any advice welcome on fitting cv driveshaft conversion

PostPosted: Sat Nov 02, 2013 8:02 pm
by Chancer
Result!!!!

How did you machine and heat treat the splines?