For my Morgan +4 I have both a welded 4.11 and a clutch type "positraction"
limited slip 3.77 axles. The welded axle behaves just as Kas says, as you
go into a corner, you must be "on the gas" if you expect the car to turn in,
so if you are going to fast, and your natural inclination is to lift, the
car will just go straight . It can be quite scary. You need to know the car
and be very familiar with the course to go fast safely. You steer the car
with power to a large extent.
The clutch type limited slip has been modified so that there is no
preload on the clutches. This is done by removing all of the "spring"
clutch plates,(the curved ones) and replacing them with flat clutches. The
housing is machined if necessary to get a total of .010" end float on the
stack of clutches. With this setup the diff behaves as if it were a Detriot
Locker. Whenever you are on the gas the clutches lock up, when you are off
the gas the diff unlocks. There is no slippage that occurs as with a
normally set up "poitraction" so there is no heat build up. The more gas
and power applied the tighter the clutches are locked up. There is not the
harsh ratcheting that the D.L. gives as it lock.s and unlocks. With this
setup if you back off going into a corner the diff is "open and the car will
turn in as if it had a normal open diff. As soon as you apply any gas the
diff locks up. There is an attitude change that is noticeable when the diff
locks and unlocks.
Regards, Greg Solow
-----Original Message-----
From: R. KASTNER <kaskas@earthlink.net>
To: BillDentin@AOL.COM <BillDentin@AOL.COM>; FOT@autox.team.net
<FOT@autox.team.net>
Date: Thursday, March 04, 1999 5:18 PM
Subject: Re: Diff Differences...
>I have a couple of comments on the rear locker situation. First off, the
>competition department paid for the tooling to make the lockers for all the
>Triumph cars. I know cause I had to find the money to pay for them. Now
on to
>handling of the various lockers etc. The locker is strong, dependable but
will
>give some understeer. The clutch type diff will have a lot less
understeer but
>is not as strong driving out of the corner cause it does slip and it also
produces
>a lot of heat because of this slippage. On our Sebring cars in 1966 it was
>necessary to run a diff cooler cause in an hours practice they all (four)
burned
>out the pinion seals and leaked like sieves. I have run TR-3' s with a
welded
>diff and if you want understeer baby this will give it to you. But boy you
talk
>about drive off the corner, when you have it set it beats anything.The
welded diff
>stops you from pointing the front in early without being on the gas. If
you are
>good this is okay but if not you are still on the gas when you are gone. By
choice
>I used the Detroit locker because it was always there and did the job. Work
out
>the little understeer with suspension settings.
>
>BillDentin@aol.com wrote:
>
>> Nick:
>>
>> Except for about eighteen months in the mid-1970s, my TR3 has been a RACE
CAR
>> all its life. I have logged about one hundred and seventy-five events
myself.
>> The car came with a Detroit Locker and a 4:1 ring and pinion. It is an
>> incredible piece of equipment. I understand it was developed for a light
>> truck, so it is VERY stout. A couple times each year it will make a
noise
>> like the rear end fell out, that is because it is mechanical, and has no
>> clutches. But when we take it apart and examine it, it still looks like
brand
>> new. I can't believe it. I love it.
>>
>> Last year we won the E-Production part of SVRA's BADGER 200 at ROAD
AMERICA.
>> Don't be impressed...two hundred miles is a long way, and we just broke
later
>> than everyone else. While we were still running at the end, we had a
broken
>> ring and pinion. Again, when we rebuilt, we found the Locker was just
fine.
>>
>> Bob Wismer and I are running a Quaiffe in the Thunder Bolt. It is
similar,
>> and smoother. It is more modern, and has clutches. I am sure it is
easier on
>> the drive line. We like it, but have not run it long enough to judge its
long
>> term dependability, and based on my TR3's experience, how important can
that
>> be?
>>
>> Last summer we set up two more axles...a 4:55 and a 3:73. The 4:55 has a
>> locker in it, and the 3:73 is welded. I know the vast majority of old TR
>> racers will tell you a welded rear end is 'the way to go' (and that is
based
>> on economies), but I can't subscribe to that. All you have to do is push
a
>> car with a welded rear end around a parking lot to decide a 'Locker or
>> Quaiffe' is money well spent.
>>
>> Bill Dentinger
>>
>> Last year we se
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