Jaguar rear end

casaleenie · #1 (**permalink**) 04-17-2003, 03:55 PM

Just made the discovery that I don't have a posi-traction rear-end.
It's an IRS Jaguar differential in a Unique FIA. What is the plus side to this or what is the minus side to a non-posi? Bought the car used and am just starting to shake it out to see exactly what I have...

Any input will be appreciated...

PTL

Chaplin · #2 (**permalink**) 04-17-2003, 04:03 PM

Casaleenie-

Here's the minus- Only one skid mark when doing burnouts

Here's the plus- Since only one wheel will spin, you can rotate you rear wheels from side to side and get twice the mileage as those with posi

KobraKarl · #3 (**permalink**) 04-17-2003, 05:10 PM

Another plus is when you stand on it ,your car wont take a walk out from under you, on the other hand you wont be able to save a bad push with the throttle.......mainly just tough to hook up on launch .....Id scout around for a posi., they come and go here fairly often....not too many of us used car buyers really get the car we wanted.....roll up yer sleeves ,its actually a lot of fun and you know theprice of the advice and abuse cant be beat .....

Karl

RallySnake · #4 (**permalink**) 04-17-2003, 05:34 PM

Casaleenie,

I ran an open rear end in my Cobra for years. Usually, in normal driving, it just doesn't matter. However, if you're trying to set a fast time on an autocross track and you power out of a turn, the inside rear wheel will spin, keeping you from accelerating. As Karl pointed out, that's not all bad. On the road, that spinning inside wheel on a slippery curve will keep you from going around backwards (spinning out). It's the original traction control.

For the racer types, this takes all the fun out of four-wheel-drifts and opposite lock steering. Personally, I like hanging the rear end out and when I rebuilt the rearend I had Hooper's set the preload tight. Now, I am constantly alert for loss of traction in the rear and ready to quickly snap the wheel over to catch it.

Paul

427 S/O · #5 (**permalink**) 04-18-2003, 01:30 AM

PTL, if you can find one, get a 89-95 H.E.
from an XJS. These are posi and stronger,
idenitified by the aluminum cover. Have whatever gears you want installed, I opted for the 2.88, I come out of first at 50, man what a ride.........

dewulfmd · #6 (**permalink**) 04-18-2003, 01:00 PM

427 S/O,

How about some more pics of your twin autolite inlines on the custom intake...

casaleenie · #7 (**permalink**) 04-18-2003, 01:21 PM

Perry,

What's required to make a\that conversion and installation into what I have now.... The basic Jag. setup from Unique???

SCOBRAC · #8 (**permalink**) 04-20-2003, 06:28 PM

C'mon.. someone say it.. Powr loc's are just BAD A$$..

KobraKarl · #9 (**permalink**) 04-20-2003, 08:43 PM

BBBBAAAAAAAAAAAAAAAAAAADDD AAAAAAAAAAAASSSSSSSSSSSS

427 S/O · #10 (**permalink**) 04-21-2003, 02:34 PM

dewulfmd, just as soon as I get the intake back from the machine shop and finish the air filters, it will be going on and pics to follow.

casaleenie, I took the dirt road in this conversion, I replaced the XKE 3.54 center section with a 90 H.E. 2.88, I also machined the stub axles to accept the rear mount disc brakes. I'll never do it again!.

Silk · #11 (**permalink**) 04-22-2003, 06:47 AM

casaleenie,

Guy here has a Unique w/o posi and was having a Jag mechanic change gear rations for him. Mechanic asked if he wanted to add posi while he was at it - and as I recall it wasn't too expensive. So it sounds like posi can be added to your existing setup.

poorboy · #12 (**permalink**) 04-23-2003, 09:09 PM

Casaleenie;

Contact Buch Capps at Mid South Gear Specialists in Knoxville, Tenn. He builds the center sections for Unique and can change yours. His # is 865-524-4800

Poorboy

casaleenie · #13 (**permalink**) 04-24-2003, 07:06 AM

Poorboy,

I'll definitely look into it - Am adding the phone # to my list...
Any idea of the cost involved??

regards,

wilf leek · #14 (**permalink**) 04-24-2003, 07:23 AM

Said it before and I'll say it again - you plain just don't need a powerlock diff for road driving.
Track/Strip - certainly, but short wheelbase cars like Cobra's "feel" sweeter with an open diff in normal road driving IMHO. Less "lift off oversteer" for a start off.

Again, just MHO. I suspect that bar bragging rights require lsd.

PatBuckley · #15 (**permalink**) 04-24-2003, 08:35 AM

Wilf-

I totally agree with you.

However, when you get a real engine you will find that a limited slip IS necessary.

Pat

KobraKarl · #16 (**permalink**) 04-24-2003, 08:44 AM

A 170 six banger wilf completly eliminate your need for a locker , of course you wilf want to keep your knickers on .......er , I mean keep yer hood closed..

Karl

wilf leek · #17 (**permalink**) 04-24-2003, 01:28 PM

Ooof! You mean bunch really know how to hurt a guy.

Would this be a good time to recall the dyno figures from DVSFII?
And what kind of tiny engine walked off with the honours?

170 horse six banger??? We don't get 'em that big here.

PatBuckley · #18 (**permalink**) 04-24-2003, 02:09 PM

I was there and I remember it clearly - the only big block needed a major tune up and the small block was 20 minutes away from grenading....!

casaleenie · #19 (**permalink**) 04-24-2003, 03:30 PM

Quote:

Originally posted by wilf leek

Said it before and I'll say it again - you plain just don't need a powerlock diff for road driving.
Track/Strip - certainly, but short wheelbase cars like Cobra's "feel" sweeter with an open diff in normal road driving IMHO. Less "lift off oversteer" for a start off.

Again, just MHO. I suspect that bar bragging rights require lsd.

I'm going to totally agree with Wilf on this. Mainly because I have an open diff and I'm too cheap to change... Besides, my wife will kill me if I come up with one more way to spend money on that car...