CV Joints

["Samuel Nelson"]

I have had CV joints in my Elan for the last 10 years {Bean type} I
would not return to the rubber type for and reason. Aprox. 40,000
miles no problems.

[tmr]

I'm in the amen corner on CV joints. I was 'converted' by Greg
Zelazek and 'Famous' Frank Filiciccia to CV's and haven't looked
back. Both Greg and Frank have had the same setup I have for decades
with no problems. I wouldn't exactly call Frank's driving
style 'gentle', nor would any of you on this side of the pond who
have seen him at 'LOG' autocrosses. Come to think of it, he did
break a diff stub axle at LOG 16 (or 18, I forget), but it was a this
original standard one subjected to years of this. Even with donuts,
they break under the same circumstances.

The conversion that we have uses VW CV joints, shortened half axles,
and CNC machined adaptors to the stub axles. Much cheaper than Bean,
etc. but I believe that you get strengthened stub axles that mount
directly to the CV joint with theirs. The shortened axles have
worked for nearly twenty years for these guys with no failures.

Tom Roberds
69 S4

--- In ***@***.***, "Samuel Nelson" <zman52164@a...> wrote:

["Carl F Peters"]

----- Original Message -----
From: Samuel Nelson
To: ***@***.***
Sent: Friday, November 24, 2000 8:23 PM
Subject: [LotusElan.net] CV Joints


I have had CV joints in my Elan for the last 10 years {Bean type} I
would not return to the rubber type for and reason. Aprox. 40,000
miles no problems.

I've had Spyder driveshafts on my +2 for the past 18 years - 80,000 miles. They have been an excellent investment and I would not go back to 4 donuts.
However I have never considered putting them on my Sprint - the car is much lighter than the +2 and doesn't really warrent them.


eGroups Sponsor

[Arno Church]

Tom Roberds wrote
The conversion that we have uses VW CV joints, shortened half axles,
and CNC machined adaptors to the stub axles.

Do you know which VW, Tom
Arno

["Samuel Nelson"]

--- In ***@***.***, "Arno Church" <stuckect@i...> wrote:


1970s vintage.

[tmr]

Arno:

The CV joints that I used are from a Type I, or Beetle. The early
cars had swing axles, but the later cars (68-on?) and the Super
Beetle used CV joints and half-axles. The transporter CV joints are
larger and I understand that these are the ones used by various
suppliers as their 'race' version. I also understand that the Type I
CV joints are used for the 'street' version. The Transporter CV's
are larger diameter and are thicker, thus they have longer splines
than the Type I does.

By the way, I have been working with a fellow engineer/Elan owner
here in Atlanta and one of his machinist friends on manufacturing a
new half-axle (vs. the 'cut down' ones). His machine shop also made
our adaptors, which turned out very well. We bought new CV joints
and used AN fasteners to put the whole thing together. We are
considering selling them as a low cost alternative to the others if
we can make the axles work out. The hardness, tensile strength, and
splines have to be correct. Will post if successful.

Tom Roberds
69 S4

--- In ***@***.***, "Arno Church" <stuckect@i...> wrote:

[Arno Church]

I will look out for your posting
In the mean time I will also report back on our current experiment with two inner VW Golf ( Rabbit)
CV joints . The adapters are ready, I am just waiting for the rear hub carriers to return, having new shock inserts made up and fitted and also adjustable spring seats and 2 1/4 inch , 150 lb springs.
Arno

By the way, I have been working with a fellow engineer/Elan owner
here in Atlanta and one of his machinist friends on manufacturing a
new half-axle (vs. the 'cut down' ones). His machine shop also made
our adaptors, which turned out very well. We bought new CV joints
and used AN fasteners to put the whole thing together. We are
considering selling them as a low cost alternative to the others if
we can make the axles work out. The hardness, tensile strength, and
splines have to be correct. Will post if successful.

Tom Roberds
69 S4

[dharbeck]

1) For the average Elan owner/driver/mechanic, does it really make sense to
muck around with a system that works well given the power of the motor, the
(relative) fragility of the drive train, and the fairly good reliability of
the donuts?

2) For the non-average (one with increased HP/torque) Elan owner (unless
you are a racer, and don't care about long term reliability), can you really
be confident that removing a nice compliant link from a mechanical system
won't result in applying unusual (read: not designed for) stress to other
parts of the system?

3) I can appreciate that a double CV set-up would be easier to install than
the rubber donuts (having spent six hours peeling the skin off my knuckles
doing mine), but if you're twitchy about working on your car, why on earth
did you buy one that was made in England?

4) Predictions about what Colin Chapman would do if faced with current
driveline technology: As near as I can tell, this guy needed things to be
cheap, available, and as lightweight as possible for the application. Does
a double CV axle meet any of these criteria? I'm guessing not very
well......

I renewed my donuts because they were dangerously checked. I don't mind the
rubbery "snap" effect I feel driving them. Isn't that an Elan thing?

David Harbeck
1969 S4 DHC
"if it's not leaking, how do you know there's oil in it?"

[elancoupe]

To each his own, I don't consider the drivetrain to be "relatively fragile".
Properly treated, the donuts are fairly reliable. Trouble is, there are
some Elan owners who NEVER look at the condition of their donuts, witness
the number of horror stories of broken donuts/cheap fasteners resulting in
mangled frames and underbodies




What parts are these? Most CV conversions use upgraded diff output shafts.
If you are abusing your main driveshaft ujoints or twisting axles, methinks
that cv joint conversions are not the problem.




I work on cars 9 hours a day, 6 days a week. Because ACBC chose to use
something lifted from a Hillman because it was cheap, doesn't mean that I
must tolerate it.




Well, ACBC used drilled brake shafts on Jochen Rindt's 72 because they were
light, that didn't work out so well either.

Anyway, as I posted before, donuts worked very well for me for many years.
Most people who make performance mods dump the donuts first thing. For a
stock Elan, I say leave the donuts alone. For a modified car, get rid of
'em. I am going on 7 years on my CV's, no problems whatsoever. The reports
of drivetrain stress are greatly exaggerated.



Mike B

[Rob_LaMoreaux]

And I'm guessing it would fit the bill EXTREMELY WELL.

Back when the Elan was designed he had two choices U-joints with sliding
slines that tended to bind up and rubber donuts, since CV joints just
weren't available the way they are today. He chose the rubber donuts
because they were cheap, available and didn't bind.

U-Joints were not good because they kept the length fixed, do a sliding
spline joint had to be added to keep the suspension from binding.
Unfortunately the sliding splines had a tendency to bind.

CV joints allow the length of the half shaft to change while transmitting
the torque without binding.

Today the situation is different. Every FWD car out there has CV joints
that don't have the sliding splines and therefore a CV jointed halfshaft is
cheap, available and it doesn't bind up. So what would ACBC use today? My
guess is he would use CV joints. Of course from what I understand he really
wouldn't have cared since Elans are old and he'd be on to other new things.

By the way what does an Elise use? What do most race cars today use?

On my Elan which is a street car I have stuck to the rubber donuts, but if
I was racing and the rules allowed it I would seriously consider CV joints,
along with chassis stiffening at known high stress areas like the
differential mounts.

On the other hand before I make any changes to my car from original I will
carefully think about the ramifications, as I have done with the few I have
made so far (limited slip diff which I couldn't resist at the price I got
it, new uprated shocks and struts, and some head work which I already
partially regret I didn't think through more thoroughly).

Rob LaMoreaux
Ann Arbor, MI 48108-1273
Home: 734-971-5583
Work: 734-822-9696
Fax: 734-973-1103
Home email: ***@***.***
Work email: ***@***.***

[camplen at aol.com]

I would say the main factor for using the rubber couplers where they were
CHEAP!
If the sliding spline binding was realy a problem why did all the race cars
of that era, including Lotus, use U-Js with sliding splines.
My 2 cent opinion.
Regards
Jason

[dharbeck]

--- In ***@***.***, "Robert D. LaMoreaux"
<Rob_LaMoreaux@c...> wrote:






Well, ditto. My Elan is a street only ride, and has received a few
updates and modifications (spin on oil filter, mini alternator,
electric cooling fan, and some minor performance mods), and I
appreciate that a racer would want to get max available performance,
but I believe that the average restorer/driver should be carefull in
making substantial changes.....or am I trying to remove too much of
the fun from the process?

David Harbeck
60 S4 DHC

[starsign]

***@***.***e:



My twopennyworth.....

Folklore of the time had it that when the Triumph Herald (which had a lot in
common with the Elan suspension) went over a humped-backed bridge it's
wheels folded under and the transmission locked up. Or was that the TR ?

Of course it may be allegorical, but then you don't get too many
humped-backed bridges on a race track.

Richard

--
Richard Burraston ***@***.***
S3 DHC 1967 (45/6352)

[saarhus]

Hi Coupling-ers,

FWIW, the 1960 Lotus F1 rear suspension had U-jointed rear half-shafts, but
with a difference. These axles had NO sliding splines, and in fact,
constituted the upper link of the independent suspension. I don't recall
what that Lotus' series number was. This is illustrated on page 56 of
"Racing and Sports Car Chassis Design" Michael Costin and David Phipps.
Not to mention, or course, that the Type 14 Elite used a non sliding spline
half shaft as its lower link.

By the way, should anyone be interested, I have a pair of unused U-Joint
sliding-spline half shafts for the Elan that I would be willing to part with
or trade for something interesting.

Stan Aarhus
66 S3 FHC
???


----- Original Message -----


Sent: Friday, December 01, 2000 3:07 PM
Subject: Re: [LotusElan.net] Rubber Donuts vs. CV Joints

[Arno Church]

If the sliding spline binding was realy a problem why did all the race cars
of that era, including Lotus, use U-Js with sliding splines.
My 2 cent opinion.
Regards
Jason

A lot less suspension travel maybe ?
Arno