Hello all you XKR fans!

With a bit (or rather, a lot) of help from Norman Durban and Tom Lenthal, I finally got a 6 speed Tremec in my XKR. So far, it works fine. On a slow and flatish journey through Denmark (I live in Sweden), I compared the consumption to whet I got under similar conditions with the auto box. With the auto, I could just get under 1L/100km (about 28mpg) :-( . With the manual box, I reduced this to 7,7L/100 (about 36mpg) with aircon ON :-) .

Of course, the real fun is the driving. I poped a short film on Youtube (Jaguar XKR manual gearbox) - check it out.

 

Now that's just plain bad ***, more details please.

 

I agree. As you can see on the Youtube clip, the car has been modified quite a lot, both inside and out. The gearbox is a Tremec T56. The ratios are quite different compared to the auto box which takes some getting used to. Comparing the auto and manual is a bit like comparing a bomber to a fighter: the auto (bomber) is smooth and comfortable, no surprises. The manual keeps you quite occupied but man, this is fun!

 

I couldn't use your link. I assume this is it:
Excellent!

Add a leather shift cover and it will be perfect.

 

That is nice. how hard was the conversion? Details???

 

Nice. Aston came with a Tremec T56 I think, I assume you used all Aston accesories (clutch, bearing, scattershield etc).

Does it use a "normal" 10 or 26 spline T56 input shaft or some special Aston only jobber? What about slave cylinder and pedals? What you did to the computer to make it all work?

 

Looks good Willafizz but we need all the details!

 

Hello again,

Yes, you had the right youtube clip (Jag#4). The link is .

The real brain behind the project is Norman D. He has designed the mechanical parts together with Tom Lenthal. The Tremec T56XL. The XL part means extra long which is needed to get the gearstick to end up in the right place (even then a small extension is needed to move the lever back from the radio a little bit). The ratios are (1) 2,97:1 ; (2) 2,10:1 ; (3) 1,46:1 ; (4) 1,00:1 ; (5) 0,80:1 ; (6) 0,63:1 ; (R) 2,90:1. In the end, we used a single plate clutch from McLeod. The bellhousing and flywheel are custom parts, as is the shorter propshaft. The engine is (now) a 4,2L with a KenneBell 2,1L s/c. The diff is also swapped for a Quaife limited slip type. All in all, very nice! Norman provided the pedal assembly - when I get a moment, I'll change the pedals so they match. Of course, the gearstick needs a gaiter but before doing that, I need to install some switches to control the digital gear/oil-temp indicator that is now integrated in the instrument cluster.

With reference to Aston Martin (which I love but can't afford!), there are no intentionally borrowed parts. If, like the gearbox, the parts are the same, it is coincidence.

Norman also provided the 'black box' which fools the engine ECU into thinking there is still an auto-box connected. From time to time, I was thinking of doing this myself but as someone else has already done it (and it is a tricky job!), it made life easier.

By the way, Norman has a similar conversion for the XK8.

To be honest, the clutch is pretty heavy and needs a servo. This will be added in due course. When up to speed, this is not an issue.

The actual driving experience is just as you can imagine: The old auto box is comfortable. You just sit back and watch it all happen. Apart from the lack of involvement, what used to bother me was the changes which only seemed smooth when accelerating more strongly. Of course, the manual box is the opposite. You get involved in a whole new way and I like that! One thing that can be worthwhile remembering is that the gear ratios are higher now. I am going to switch down from a 3" to a 2½" upper puller on the s/c to compensate.

One thing that would be interesting is to push the rev limiter (now around 6000rpm) up a bit. From what I understand, the engine will cope with higher speeds - the reason for the low upper limit is the torque converter.

-> Is there any setting in the engine ECU that can be adjusted?

Of course, the brute force solution is to use another ECU. This may allow for some better engine settings.

 

I was never a fan of the Jaguar ECU which is why I used a standalone system some 15 years ago when I did the conversion...... I used the T56 from a Dodge Viper, it came my way at the time...... I now have it in my XK8 track car

 

Willafizz, get to see this kind of work being done, for those of us that can only dream about having this done, what is the neighborhood cost of this conversion?

 

Well, the cost is the downside of course. Actually, I can't even remember what I paid but it was around 5 grand for the manual box and peripherals. The installation is a further £1200. Norman D can give you a proper quote is you like.

 

Pounds or dollars .... or kronor

 

I'll trade you a slightly used rebuilt automatic tranny for that.

It's a good deal, you should take it.







But really, you need to do a write up

 

All figures in GBP.

 

hhhhmmm, nice project. wondering what exactly the intention was, reduce in fuel consumption? if it was to make a sports car out of it, i would have choosen anonther brand.....

 

That's about (USD) $10,000 total.

I'm impressed that it's been done.

 

Just so there is no misunderstanding - of course, I havent just spent x thousand quid on this sort of car to save a little fuel. It was just a note for general interest. I think part of the saving comes from the higher ratios and the other from a less lossy setup. The second point is another way to say 'more available power at the rear wheels'.

The main interest for me is the involvement factor. I don't use the car as a 'daily ride' - it's a hobby, a passion, ...

 

Nice. Seems to me you have created an XKR-R.

LSD, + more output, + manual transmission = XKR-R

 

I'd do this in a heart beat if I had the extra cash for this kind of thing. Not having a manual gear box is my biggest dislike of the XK8.

 

Now I have the manual box, it allows me to compare the two. I never thought I would say so but I understand why such cars are made with auto boxes. It all seems so smooth and refined and comfortable. What a ride. The manual box needs more attention and it will take some time to learn to drive it properly. But if you like that sort of thing (and I love it!) you simply can't get enough of it!