Manual Gearbox

[johndiller]

Here we go, in at the deep end with the big XJS Manual / Automatic debate.

After much thought and research (and the fact that i have to pull the box anyway to solve some leaks) I have decided to go down the Manual box route.

I am most drawn to a Keisler type kit using a tremec TKO-600 5 speed with .64 Overdrive.

However the Keisler kits are from the US so expensive to ship, will be subject to HM Bloodsuckers duty and will have peddle boxes for LHD.

I was wondering if anyone here has had experiances with Keisler Kits / Tremec boxes or knows of UK based versions of the same?

Also interested in any info or suggestions that anyone may have for other alternatives. I am not after a track day car but rather something that will be able to cruise at Autobhan speeds with less revs and possibly even give better MPG to boot. (plus a it of engine braking ability would be nice too )

Intention is that this will be fitted up to an 1982 HE

[Martin]

Can't help with the questions, but one point interests me. I get engine braking with my auto box - but mine's a 3.6 with the ZF box. Is there no engine braking on the V12s?

[poprivet]

Possibly due to the torque converter lock-up clutch on the 3.6?
Engages around 55mph on mine, feels almost like a fifth gear. (Definately more engine braking on the 3.6 xj-s then my previous SIII V12 Sovereign had.)

[johndiller]

Perhaps i should clear up something here ... the V12 does provide a good level of engine breaking on motorways, but i was referring more to smaller roads. Especially a moment i had earlier in the year when i took her down to the Nurburg ring, somewhere that i have done many laps before in BMW's and caterhams. Lets just say that you REALY miss the manual 'Box then!!! (i almost s**t myself )

OK so maybe some track'ish days.

My main reason for the manual however is higher cruising speed and lower revs. The keisler website has a conversion table that shows 1,700 rpm in 5th gives 80mph ... think of the fuel saving, i may even see 25mpg!!

[Snapper]

John,

I have a '92 facelift auto 5.3 V12, and have the same desire to go manual, or I suppose fit a later electronic 4-speed with lockup......don't know who to go to though.

I'll watch for answers here as well if anyone has ideas.

Regards

Gareth

[NeilMFox]

Yes had my V12 conv 1990 converted to manual and very pleased with it on a long run got about 23mpg. Got the feeling the 2;88 diff made it too high geared in top so changed to a 3;54 which was much better.
Gear box used is a five speed getrag spoke to those who know who used the same box in racing as was concerned it was not strong enough.
Contact John Thompson on 01306 711134 he normaly has the bits and can put you in touch with some one to do the job if you dont want to do it.
Carefull to get a good box these are not easy to overall.
Any probs let us know.

Neil.