Hello! I'm looking to pick up an XJS within the next year, and having driven cars with the TH400 3-speed before I don't know if I could bring myself to leave it in the car for any reasonable length of time. I would look at other cars but between the jag v12, the beautiful body styling of the XJS, and the low used value compared to other classics I'm interested in, this car has only one drawback: the transmission.

So here I am looking for info on manual swaps. After doing some reading, I've heard that there's a supra W58 swap using a bellhousing from Dellow Conversions in Australia (this would be my preference cause I like this trans) and was wondering if any of you guys have done this swap. I have read a couple build threads that say the kit offered by Drivenman is backed up by horrid custom service and regularly missing parts, despite being the only non-custom-fab solution on the market. I know there's a variety of solutions for the T5 and T56 transmissions, and then there's the Getrag 265 if you can find one. I'm leaning towards the W58 swap, because I like feel of it, and the bellhousing is fairly cheap (700 AUD, so 700 US with shipping) I can source a W55 or 58 locally and I'm comfortable with the fabrication necessary, the only custom work I'd need to source would be a driveshaft. I believe the whole swap could be done for 3-4 grand. Of course, I'd love to hear about any other manual swaps - I'm not sold on the W58. I just want a stick in this otherwise wonderful car.

 

Of course I can't spell the first word I type on this forum. I blame cold fingers.

 

Your biggest problem would be scourcing a manual pedal box. Depending on what year your car is, you'll be wanting one with the ABS block at the same time. These boxes can go for a lot of money, as they are getting rare and scarce...

 

So my plan is actually to use a pedal box from an S2000. I love the pedals and spacing on those. I've lived my life this far without ABS, I just plan on having decently sticky tires and good brakes. I would use the transmission from an S2000 but there's no adaptor for it and precision fabrication is past me (I'm fine with building mounts, brackets, cross-members, etc)

Is there a way to edit the title? It's bothering me.

 

Dellow engineering supply a pedal box for xjs conversion and also bell housings for tremic gearboxes .i had a supra gear box in a v12 and hated it. I dont think it ideal for the jaguar

 

what was the issue in particular? the gearing? That's a result of the super long rear diff stock in the jag. There are certainly some options for fitting a shorter ratio in, by either buying a diff from another series 1 jag IRS setup or by fitting a shorter ratio into the Dana 44 diff on some of the XJS's (and yes, I know this is easier said than done).

As it stands I like the ratios in my 5 speed civic (3.462, 1.87, 1.241, .97, .711 with a 4.111 final drive) because I get to rev out the whole rev range in multiple gears before I'm going wholly too fast, but I actually spend some time in each gear. As it stands, with a swap to a 3.77 rear end (either by swapping out the gears in the Dana unit or finding a unit from a manual XJ6) the W58 is just about right for my needs - a bit longer gearing suitable for the higher power output of the V12, but similarly spaced to my civic. For ease of comparison, with stock wheel diameters, my civic tops out each gear at 34, 63, 95, 122, and 167 MPH in each gear respectively and the W58 with a 3.77 rear differential tops out each gear at 41, 72, 107, 137, and 176.

Just about any manual swap will struggle with the existing jag rear end, except for maybe a close-ratio box designed for a high RPM motor like the S2000's gearbox. It would tighten up the gear spacing, but given it's reliance on a short final drive ratio (4.1) it still struggles with the long 2.88 gears.

This is worrying, the more thought I put into this. I want to up the V12's redline (more to hear it scream than for the power, although some intake work should solve that) and that only exacerbates the seriously long rear.

In theory it's possible to put Dana 4.11 or even higher gears in there, but at that point there's no longer a jag diff to swap right in and you've gotta do it the hard way.

 

[QUOTE=jtmote;1625605]what was the issue in particular? the gearing? That's a result of the super long rear diff stock in the jag. There are certainly some options for fitting a shorter ratio in, by either buying a diff from another series 1 jag IRS setup or by fitting a shorter ratio into the Dana 44 diff on some of the XJS's (and yes, I know this is easier said than done).

As it stands I like the ratios in my 5 speed civic (3.462, 1.87, 1.241, .97, .711 with a 4.111 final drive) because I get to rev out the whole rev range in multiple gears before I'm going wholly too fast, but I actually spend some time in each gear. As it stands, with a swap to a 3.77 rear end (either by swapping out the gears in the Dana unit or finding a unit from a manual XJ6) the W58 is just about right for my needs - a bit longer gearing suitable for the higher power output of the V12, but similarly spaced to my civic. For ease of comparison, with stock wheel diameters, my civic tops out each gear at 34, 63, 95, 122, and 167 MPH in each gear respectively and the W58 with a 3.77 rear differential tops out each gear at 41, 72, 107, 137, and 176.

Just about any manual swap will struggle with the existing jag rear end, except for maybe a close-ratio box designed for a high RPM motor like the S2000's gearbox. It would tighten up the gear spacing, but given it's reliance on a short final drive ratio (4.1) it still struggles with the long 2.88 gears.

This is worrying, the more thought I put into this. I want to up the V12's redline (more to hear it scream than for the power, although some intake work should solve that) and that only exacerbates the seriously long rear.

In theory it's possible to put Dana 4.11 or even higher gears in there, but at that point there's no longer a jag diff to swap right in and you've gotta do it the hard way.[
well my friend I'm not an expert but id didn't like the way the box shifted and i dont think it would be strong enough. Dellow can supply a whole kit I'm not sure where yu r but in australia ford an Holden v8 run good boxes an thats what fellow uses they're not that expensive and I'm pretty sure yu can customise the ratio's From memory i think the 6060 box hAs two gear stick position so it may fit with not a lot of trouble.
i think Aston Martin uses that box for auto/man conversion . I'm not sure about that tho

 

I'll look into american transmission swaps. But for reference the W58 transmission I would use is the one behind the twin-turbo 2JZ, and should be perfectly capable of the V12's stock output. Something more durable would be preferable for any power mods.

 

There's been a lot said on the auto to manual trans conversion. My first is suggestion is reading the archives. My experience and my opinion is go with a complete new everything kit & expect to budget est.$7K USD for parts, going this route and that's doing the labor yourself. Piecing the conversion (part here,part there) can be very frustrating to say the least, and even more costly in the long run, especially wrong parts & that don't fit & shipping cost in & trying to return/exchange the parts that don't work.

 

I'm struggling to find a way to get the gearing I want. I suppose going with the basic tremec T5 swap and changing out the Dana 44 gears in the diff is the most obvious solution.

 

What's your goal, highway or stump pulling gearing ? I wanted the same "feel" as my old Corvette with close ratio 2.20 first & 1.1 forth with a 4.11 diff. I feel I got it all that with my Tremec TKO 600 5sp.and 3.54 diff.plus the OD Fifth gear, .82 Example: 60 mph = 1,800 rpm (level straight road) in 5th gear. Six speeds are different, most have two OD's. cost more & more work to fit. Do you need two OD's?
There's a ton of trans gearing & diff combinations.

 

I like revving engines out so I want something a little long but I also want to be able to rev it out multiple times without breaking 3 digits. You know, so I can actually use more than one gear to it's full potential. I'm thinking first goes to 40, second to 70, third to 100, 4th to 130, and fifth does 75 at 2000 rpm.

 

TKO 600 with the 0.64 5th & a 3.54 diff then (on 225/55/16s): over 40 in 1st @ 6,000rpm, 67 in 2nd @ 6,000rpm, 99 in 3rd @ 6,000rpm, 127 in 4th @ 6,000rpm & 82 in 5th @ 2,500rpm.

Rgds.

A.

 

That sounds just about right. Are 3.54 differentials hard to find? I couldn't find anywhere that sells them (or even just the gears). Is it the same as the 3.58 out of the XJ6? I know Coventry West has those rebuilt.

Edit: the 3.58 won't work. I called them. Damnit.