I am thinking of buying an XJS V12, and then converting it to a manual transmission. Rather, having a shop convert it to a manual transmission.

I have found a bunch of threads where people did the conversion or were planning on doing the conversion, but I have found very very little about how much it actually cost, since many of these people are doing the conversions in their own garages!

Does anyone have any idea how much it would cost all in? I was thinking if the Driven Man TKO500 transmission kit, which seems to cost $5000 US. So I was hoping another $2500 or could include the labor?? What do you think?

 

I've literally just had mine done. My conversion was to the Gertrag Gearbox using an AP Racing clutch. The basic price for the gearbox conversion and fitting was £5500. There were a number of 'other' things that needed doing too bring the total up closer to 7k....

 

Yikes. I wonder what the price would be stateside.

How do you like the conversion???

 

I guess one thing I'm noticing when reading about other conversions is that the ABS models cost quite a bit more to convert, because the ABS pedal box is much more expensive. So if I buy an XJS, I will probably want a 1982 to 1988 model.

 

I received a response from The Driven Man:

20 to 25 hours does seem reasonable. That would mean installation would cost something like $2500 at most indy shops, no?

 

FYI, he says S&H costs to the DC area would be something like $225, and they can ship it to a shop or they can ship it to my house.

 

I just got an actual quote from a performance shop here. He said as a rough estimate, they would want $7000++++!!!!!!! in labor. That seems extremely high to me!

 

That does seem rather high, may I suggest you call some of these installers:

Installers - The Driven Man - Specialty Auto Performance Parts & Accessories

If they've done the job before, they won't have to pad the quote because they don't know what they're in for.

It might be cheaper to ship the car to someone who has done it several times, rather than find a local who has no idea.

 

The interesting thing was that when I emailed with Driven Man, they said they didn't know of any installers in the Mid-Atlantic, but that they'd be happy to talk to my preferred shops to gauge their level of understanding??

 

Flying Circus in Durham NC is listed. Nice shop. Knowledgeable owner.

Flying Circus English Cars

 

Why would you pick the TKO 500 over the TKO 600 5sp ?I did mine about 7years ago for about $5,800. I went with the aluminum flywheel and had to get my computer reworked (AJ6 was $250 + S&H to UK) because of stalling between shifts. Cost: better budget around $6K doing the work yourself. Its a lot of work, but as said its a straight forward job. It can be done on the garage floor also,you must have trans jack and all the basic tools. Good Luck
Lawrence

 

i sold a complete running 1975 XJ12C coupe for $6500.

manual shift transmission!

seems like a lot of money for a conversion. my 700R4 cost me $200. ,shift kit cost $100. mounts and small stuff around $100, and hi-performance converter $250., then sold the Jag/GM 400, for $300. bucks.

did all the labor myself(i'm one of those that likes to do all i can myself).

i drove both of my cars ,1978 XJS V12, with 700R4 conversion, with kit so as to shift up or down gears and hold in any gear!

against the 75 coupe V12, manual trans, and to be honest, not much improvement in performance!

seems more like a novelty, but YIKES, 5000 to $7000.

and yes ,i know to each his own preference!

hey you got the money Honey, they got the time.

 

Hey Ron it is a lot of money. A new TKO 600 5sp is around $3K, new aluminum flywheel $350est. Sending the computer to (the UK) Roger Bywater to rework WAS around $350 . Throw in the Ram throw out bearing set up, pedal box alterations, Zoom clutch, one piece driveshaft and S&H and tax. Do the math. If you're lucky enough to find a donor car with a 5sp that used parts will do, go for it.
Lawrence

 

OK , if you do a manual conversion, does that mean you will absolutly be faster than a GOOD automatic transmission?

todays modern cars have 6-7-8 speed automatics, with much smaller engines, and you may not be as quick,with a manual.

true in engineering(Audi).

 

In this case, I think maybe yes. Here's why: "today's modern cars" also have a computer to run that 6-7-8 speed. That makes for better shifts, and less waste of power. You might be able to cobble it to the 12, but the electronics will require some sorting.

One of the best reasons to update the trans in these cars is that the TH400, while reliable, really doesn't suit the car... especially mated to that 2.88 rear end. There are some interesting calculators on the driven man site that shows what gearing can do. Change to the 5 speed, and change the rear end to something like a 3.54, and you'll have a much quicker car, and a tall 5th gear will have you loafing the engine on the highway. You'll probably have better acceleration
and better gas mileage all at the same time. You could probably do the same thing with a "modern auto", if you have the skills. Up to you.

 

For me the conversion would be all about the fun. I'd love to make believe I'm Tom Walkinshaw racing around town!

 

relevant to topic:

Richmond Transmission

 

Beavis, please let us know what it feels like, the difference, the improvement, etc etc!
Greg

 

I must agree with amcdonal. Its all about fun & reliability . Gas mileage, racing & 100mph+ speeds are all irrelevant, @ least to me. As in my case the TKO 600 5sp is as good as it gets. Throw in a 3.54 rear and you got the best of all worlds. Fifth gear is 1,800rpm doing 60mph on level road.
Cost, yea its expensive & don't look @ this as an investment, chances are very good you won't get any thing spent on this back. I believe XJ-S owner's are very aware $$returns$$ on the XJ-S.
Lawrence

 

That's the same transmission I have.
Its a lot more expensive than the TKOs, and, it requires surgery on the transmission tunnel (not a huge problem if you have the nads to cut a big chunk out of the side of the tunnel to make room for the linkage), but, in my opinion, it's a much better transmission than anything Tremec will ever make.