Any of you guys used one? They sound like fun to me, but I don't know how a solid front axle and IRS rear would handle! Any quirks? Also looking for a picture of one on a fenderless car, everybody seems to run them on full fenders... how do they look naked? Thanks
Back in the '70s every self-respecting custom in the UK had a Jag rear - Pops (Anglias), early Fords, vans, fad-T's, trucks, you name it. They've gone out of fashion a bit these days, especially since the revival of traditional rods and the cheap availability of ready-to-use axles from the likes of Curries, but they can still look great especially on something like a fad-T. They can be expensive to rebuild - lots of bearings, shims, etc. to replace if worn out - but if set up correctly can give a good ride and handling. Also a lot of parts to polish if you want it chromed! Street Rodder did a series on Jag rears from March through June '95. I also have some scans of a series from the UK's Custom Car that I could email - there're 12 pages of about 400KB each, unless I can shrink them a bit - PM me if interested and your email can take it.
An IRS will ride better in a light weight car, as it has less unsprung weight. If you are running a beam axle up front, my sense is that you will want to make sure that you retain some understeer. (and some weight on the front end) Way too many '60s and 70's vettes went into the woods around here upon taking a turn at excess speed. If the rear breaks loose, then you can slide it around the turn...if the front end breaks loose first, you've got a problem. There should be some older rod builders here who have first-hand experience setting up this particular arrangement. I ran IFS and IRS, and simply managed to keep the front end glued down when cornering. You might ask Johnnyfast(?) and the circle track types. The Jag used a number of GM parts/bearings if I recall correctly which should lessen the pain in the pocketbook.
Farna here on the HAMB has installed Jag into a project(s) of his. His was for a driver not muscle though.
IIRC the Jag pumpkin is a Dana 44 with halfshafts and inboard brakes. Gears,bearings, LSD's and such should be cheap enough thanks to the 4-wheelers using D44's in Jeeps. Shawn
Just remember they were built for heavy sedans, so most uk rodders ran with just one spring each side or much lighter springs. A typical rod probably wouldnt compress the springs at all heavily chromed, they certainly were popular 20 years ago. I remember most rods using them had an extra brake light underneath that was on constantly to shine off the sparkling half shafts.
Cool stuff. Thanks guys! Prices are a bit higher than I was thinking... Are the 60's/70's vette comparable? Sure are cheaper, though not nearly as good looking. Hmm. Most of the magazines are talking late model vette parts... I want something a bit more of the period! Thanks
Well, you're right at first, then wrong with the last part IMO. Understeer is much safer - when a car feels like it's pushing into the corner the natural reaction is to remove the gas, which will fix the problem. All family cars understeer for safety reasons. Putting oversteer into a car (feeling "loose" in the back) is much more fun/fast for competant drivers that are expecting it (sports cars, hot rods, racers) but it requires more skill. Nothing like a long noisy 100mph sideways opposite-lock corner to get you grinning
Agreed about the understeer. What I meant by loss of traction was that if you lose steering capabilty, as the vette's seemed to, then you are headed for the woods! None of the beam axle street cars I drove felt as "sticky" as the IRS once the springs and shocks were set up. (I kept the entries listed in 1st post separate for that reason.) The 60's-70's vette IRS is a reasonably easy set up, it helps to extend the frame 4-5 inches and drop a 2x4 vertical post down to mount the rear of the pumpkin. Use a deeply dropped "trans. tailshaft" style mount for it's front. Then start subtracting leaves from the spring till you are satisfied w/the ride. There are several spring types and thicknesses available.
So far I like the Jag rear I built for my street-legal sprint car. It was a bunch of work however. I had to offset the right side pivot points 2" to get the pinion centered. You can see the 2" aluminum spacer next to the rotor and the 2" tube spacers at the bottom arm pivots. That made it 63 1/2" wide over the wheel mount flanges so I narrowed the lower arms and the half-shafts 6 3/4" each to get the width down to the 50" I needed.
I considered using a Jag rear back in the 70's. I went to the junkyard and they had a whole assembly out of the rear of an XKE, I tried to move it and it felt like it was nailed to the floor - it was heavy! But, they are really strong and if memory serves, even some Stude gears fit if you need taller than Jag ratios. Geometrically, they are not very interesting with a fair amount of camber change and they use the driveshaft for the upper suspension arm making them, effectively, like an old Stingray. The fact that you can crank in some negative at the rear will give you more rear tire adhesion than the fronts. So, if understeer is safer for you, it should do the trick.
I put one in my 33 roadster i built in 1976 and its still there and is fine.Everyone who rides with me says how good it rides. Around here XJ6 front and rear ends are getting used in 46-48 fords. Cheap too.
Thanks Rem, I joined HAMB to try and learn about Jag rear ends. This was the perfect answer. Went to my collection of old mags, pulled the 4 issues and have a ton of info. THANKS! I'm building an art deco roadster similar to the Bugatti design thread that was on MetalMeet.com last year. Similar in style but not much else. It has a Dakota front crossmember and suspension, Jag rear, 318 Chrysler and 4speed auto. Kerry Pinkerton Imperial Wheeling Machines http://wheelingmachines.com
What is involved in replacing the bearings (ones in the hub) of an late 60's early 70's jag rear end.
I think they become very interesting when car weight starts getting below about a ton... at that point, you have a ridiculous sprung/unsprung weight ratio with normal axles and there's not much you can do about it. Going independent greatly improves that. When they were popular, they were also used with Jag front end pieces, reducing unsprung even more. R&C did a handling shootout test back then between a traditional Deuce and a Jag equipped one...test was on kind of shaky ground as neither car had had any real handling development and both had bigs&littles (I think they put identical tires on the two cars, though). The solid axle one won the test by a small bit.
I have put Jag front and rear in my Lincoln coupe. Should ride like a dream... In New Zealand it seems every second rod & custom has a jag rear in it. You can pick up a whole car for just few hundred bucks.
Bruce, If you are referring to the "Duel of Dueces" as reported in Rod and Custom way back in August '72, which tested Gray Baskervilles car against a similar Jag sprung car of Jerry Kugel, then the article records the outcome a little differently by my reading. I agree that the test was perhaps not as rigorous as as it could have been. P20 for those that have the magazine in question says: " For the guy who is interested in making that 6000 mile rod run, no way can you equal the handling ,braking and ride qualities of a fully independent suspension. For the typical weekend kamikazi , whose rod is basically a car port queen, he might better spend the rocks on more chrome and metal work............" The brake test provided the following figures: Baskerville 44ft. @ 45 mph Kugel 15.4ft.@ 40 mph That said I'm not about to swap my beam axle front end out for a Jag anytime soon.
I've been playing around with Jag stuff since the '60's ,,i've had 6 Jags over the years ,both 6 cyl and 12 ,,4 door sedans and a XK E type anna XJS coupe ,, a year ago i sold one of my spare Jag Rears to a guy building a show '69 Camaro ,and reciently sold a XJ-12 Parts car to a hot rodder building a '39 Ford sedan ,,,,, Parts are easy to get ,,Engle Imports in Kalamazoo,Mich has a 747 Cargo Jet coming in every month from England full of parts ,and priced right too ,,,Koogle makes and sells trick bushings to replace those Jag problematic rear bearings ,, in a light weight car ,,replace those stiff shocks that are designed for a 4000 lb car ,,with Chrome QA-1 Adjustable shocks from Speedway ,,just tell the tech guy approx how much your car weighs ,,he'll design the 4 shocks for you ,, Ain't nuthin' cheap these days ,,just remember ,,you only get what you pay for ,,,sometimes cheap ain't the right way to go in the long run ,,,
Not sure what you think is high. 3 months ago, I bought the IFS, and IRS from a XJ12, for $295 on Ebay. The XJ12's had posi rears. I see good donor Jags for $300-$800 often, and you would also then have the IRS to sell
At the Decatur TX swap meet there were at least 2 Jag XJsedan rears at $350 each. One of them is going under the new T bucket which should should be alive by Spring.
I want to add that TSM used to make a stock Ford 9" pumpkin IRS conversion years ago if you want to look into it. http://www.tsmmfg.com/Rear_Disc_Brake_Kits.htm I only mention this b/c I figure one would be dam near bullet-proof! Maybe w/ in-board disc brakes, but I may be off here b/c it's been years and years! And I have their old cat. w/ this info in it somewhere. pdq67
I put a XJ rear under a 50 F1 pickup, it worked really well. My local pick a part when it has them sells them for $120 a time. Easy to remove as you unbolt the whole cradle. Also they are easy to narrow, thats why they were being used a lot in Ford Pops back home in England.
a quick note; XJ-6 rears are 3;42 0r 3;08 non-Posi,,,XJ-12 rears are 3;90 gears and a Posi ,,i sold my complete spare XJ-6 rear for $300 bucks ,,i sold my complete '73 XJ-12 Parts car ( 'cept the front seats that i used in my '27 T & the front bumper guards i used as nerf bars on the "T" ,,i sold the complete wood dash & guages for $300 bucks ,, ),with the V-12 engine and trans & complete front & rear IFS for $950 bucks ,,he sold the engine & trans for $550 ,,then used the rest of the parts car for his '39 Ford sedan street rod ,,had $400 in the whole Front & Rear suspension / plus all the rest ,,,, There's a huge Jag junk yard in Dallas Texas ,,Johns Cars ,,they do Chevy V-8 and Buick V-6 conversions in Jags & Triumphs ,,they have a bunch of Jag IFS & IRS stuff fer sale every day ,,cheap ,,Google em and see ,,,
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