Does anyone have any experience with the complete EMPI CV/axles available for 1965-68 cars? I found them on the bird and they are very low cost ($69ea). I'm a member of the "you get what you pay for" club and the "take a good deal when you find it" club so I'm somewhat torn on these...
Alternatively, does anyone know of a good source for OEM SWB axles (used, rebuilt, NOS)?
Many thanks,
Jim H.
They are great, they have better boots than the originals, and come apart the same way. I think the GKN are still available at like five times the cost.
1966 911 #304065 Irischgruen
I bought them as well. Work great at a great price. Although I did have an inner boot pull away from the swedged clamp. They gladly replaced the entire axle assembly for me...no hassle.
Note that they only come partially packed with grease. You will have to pull the boots back and pack them thoroughly with additional grease.
Thanks for the feedback. I was hoping to hear some good info.
Interestingly, I called and talked about these and the seller's rep said they had some returns and perhaps a used set of GKN would be a better option.
Anyone here return a set?
If you contacted Sierra Madre, it was probably mine that I returned recently for the boot separating from its swedge, but the axles function as they should.
I understand from one of the Race Community that these EMPI axles have a very short life and that they may be discontinued. They have been replacing these shafts after 2-3 races due to both high wear rates.
I have been looking at this issue for some time and the engineering behind the current solution from either EMPI or GKN Spidan is not great.
The original uses 25 spline CV joints with +/- 12.5mm of plunge.
The GKN Spidan and the EMPI shaft both use a CV joint with 33 splines and +/-8mm plunge.
The reduction in plunge can lead to problems with wear of the joints depending on where the centre part of the joint sits in relationship to the housing as when the ball bearings become close to the ends of their respective tracks they can wear/fail.
GKN have made this issue worse by making their 'new' replacement shaft 10mm shorter than the original.
This means that it will still assemble but will use up a proportion of the plunge in a 'neutral' position and it is more likely to arrive at the position which causes trouble.
I don't know how long the shaft is that EMPI use but the fact that the gaiters pull apart is a clue to the fact that it may also be short and reaching the limit of its travel.
There are two solutions that spring to mind other than to fit cheap shafts and monitor their condition regularly
The first is to use a Stock Lobro Joints with 33 splines and to make a batch of suitable shafts that are around 10mm longer than the current 25 spline shaft (20mm longer than the new GKN Shaft) as this will resolve the issue with regard to plunge. It is also possible to buy a custom made 33 spline joint with increased plunge and a suitable shaft. I believe the total cost of this solution is around $600 per axle.
The second is more complex and involves making new flanges for the transmission and the Hub and use 25 spline 100mm diameter Lobro Joints that have +/- 14mm plunge with the existing shaft.
Existing shafts have rolled splines and are excellent quality and making a replacement would be relatively costly.
We have decided to make new flanges to suit the 100mm joint as flanges are also becoming worn and having replacements seems a good idea.
We are also waiting of the cost of buying a batch of rolled spline shafts manufactured from 300M for serious racers.
It is also possible that the EMPI shaft is OK on gently driven low mileage cars but I don't like the consequences of a catastrophic failure.
I used to use Beetle half shafts in my SWB 911s with Cv joints rebuilt by a California off-road racing place. They were inexpensive and worked well for me. I don't drive gently. the empi halfshafts are probably intended for VW like most of their products.
I think the EMPI/Spidan shaft is a 1302S part and my only concern is to do with plunge, we fitted one up a couple of weeks ago with the gaiters off and at full droop its all a bit too close for comfort when you measure with the shorter shaft and reduced plunge.
I think it would be a problem on rally cars that jump off the ground - unless you fitted check straps to limit droop.
It is possible to buy a 33 spline joint from some of the VW guys modified with increased plunge but you can't find a 25 spline 90mm of 94mm OD CV any longer so you always have to change the shaft.
This is the comment I had from one of the guys in the USA that set me off looking at the issue:
I had those cheap EMPI shafts in my car and they only worked for 2 or 3 race weekends . . .then blew up the CV.
And, I just heard that EMPI is no longer going to make those so we are now completely out of luck.
I did notice the plunge issue while packing additional grease into the new CV joints. When placing the joint at a sever angle, I could get the balls to drop out. I just didn't see my street car ever placing the CV joint on that sort of stress angle. Empi has been making CV axles for over 40 years and most venders still carry their products to date. And I don't plan on taking any jumps in the near future with my 911
Having your balls drop out is always a problemOriginally Posted by gsjohnson
I did notice the plunge issue while packing additional grease into the new CV joints. When placing the joint at a sever angle, I could get the balls to drop out. I just didn't see my street car ever placing the CV joint on that sort of stress angle. Empi has been making CV axles for over 40 years and most venders still carry their products to date. And I don't plan on taking any jumps in the near future with my 911and it just depends when I happens and this is the point I was trying to make.
It is just not good practice to engineer parts that can fail in unexpected circumstances and I believe that any part should function both safely and reliably from full bump to full droop.
I can accept that many street 911s will never jump but where I live we have many small roads and many hump backed bridges and from time to time we can take off.
Our rally cars jump on a routine basis sometimes 4-5 feet off the ground and as I have suspected for some time these shafts could be a problem.
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