XJS V12 Manual Conversion & ITB's & Maybe TWR Rep
Discussion
I've been plotting and scheming about buying an XJS for £10-15K and then modifying it tastefully.
I'd love a Lister XJS but that seems to be a little out of budget, £60K for a good one now it seems. I'd need to sell two other cars I like to get close to that.
These guys do a manual conversion:
https://simplyperformance.com/v12-5-speed-conversi...
I was then thinking of fitting individual throttle bodies and a fruity exhaust, no doubt at considerable cost. Perhaps run it using something like and Omex 710 ECU.
I have some experience with this as I fitted an Omex 600, Throttle bodies and twin coil packs to my 1966 Alfa Giulia, it's been great over the last three years.
The TWR rep bit I'm not sure about, I do idolise the 1984 TWR XJS, but I don't want to look too naff.
Has anyone driven a manual V12 XJS conversion?
I want to create something that looks and sounds mean but in a well thought out form.
Biggest question is, which car would be the best to modify? Engine wise there seems to be the Pre He 5.3 (too old and scarce?) HE 5.3, 6.0 TWR or the later Jaguar 6.0 unit?
Then there are different models over the years, eg the Le Mans special edition etc. Do some of them have a LSD?
Thoughts?
I'd love a Lister XJS but that seems to be a little out of budget, £60K for a good one now it seems. I'd need to sell two other cars I like to get close to that.
These guys do a manual conversion:
https://simplyperformance.com/v12-5-speed-conversi...
I was then thinking of fitting individual throttle bodies and a fruity exhaust, no doubt at considerable cost. Perhaps run it using something like and Omex 710 ECU.
I have some experience with this as I fitted an Omex 600, Throttle bodies and twin coil packs to my 1966 Alfa Giulia, it's been great over the last three years.
The TWR rep bit I'm not sure about, I do idolise the 1984 TWR XJS, but I don't want to look too naff.
Has anyone driven a manual V12 XJS conversion?
I want to create something that looks and sounds mean but in a well thought out form.
Biggest question is, which car would be the best to modify? Engine wise there seems to be the Pre He 5.3 (too old and scarce?) HE 5.3, 6.0 TWR or the later Jaguar 6.0 unit?
Then there are different models over the years, eg the Le Mans special edition etc. Do some of them have a LSD?
Thoughts?
Thank you for the encouragement guys 
Thinking about things more, It needs to be 1992 or prior as I don't want to have to run cats; performance and sound wise.
I quite like the Pre HE cars, but I think realistically a good HE might be the best bet and with the most cars to choose from.
I also found this (look at the price but wow!)
https://store.jenvey.co.uk/jaguar-v12-e ... ckjr04-kit
Whether that would fit under the low bonnet of the XJS I'm not sure, but imagine the sound a throttle response!
Simply Performance have a demo car so once I have sold my other car I'm going to go and have a look at that to give me an idea.
_I'm a little all over the place at the moment as the range is so broad, but the options seem to be_
Bag a nice He 5.3, actually prefer the interior of earlier ones, for example, I've spotted a nice 1982 one for sale.
XJR-S 5.3 - I actually quite like the bodykit.
XJR-S 6.0 Pre Facelift Attracted by the 6.0 engine but scarce and the price etc. Difficult to repair Zytek engine management, probably would replace anyway.
XJR-S 6.0 1992/3 Facelift - A couple that look good value but I don't like the rear lights as much and they look like the heaviest version.
Also what is the actual cut off for running a car with no cat's legally?
I thought it was 1992? Would a facelift 6.0 be legal with no cats?
Confusing things is whether you "pass an emissions test" with cats or not.
Thinking about things more, It needs to be 1992 or prior as I don't want to have to run cats; performance and sound wise.
I quite like the Pre HE cars, but I think realistically a good HE might be the best bet and with the most cars to choose from.
I also found this (look at the price but wow!)
https://store.jenvey.co.uk/jaguar-v12-e ... ckjr04-kit
Whether that would fit under the low bonnet of the XJS I'm not sure, but imagine the sound a throttle response!
Simply Performance have a demo car so once I have sold my other car I'm going to go and have a look at that to give me an idea.
_I'm a little all over the place at the moment as the range is so broad, but the options seem to be_
Bag a nice He 5.3, actually prefer the interior of earlier ones, for example, I've spotted a nice 1982 one for sale.
XJR-S 5.3 - I actually quite like the bodykit.
XJR-S 6.0 Pre Facelift Attracted by the 6.0 engine but scarce and the price etc. Difficult to repair Zytek engine management, probably would replace anyway.
XJR-S 6.0 1992/3 Facelift - A couple that look good value but I don't like the rear lights as much and they look like the heaviest version.
Also what is the actual cut off for running a car with no cat's legally?
I thought it was 1992? Would a facelift 6.0 be legal with no cats?
Confusing things is whether you "pass an emissions test" with cats or not.
lukeharding said:
urquattroGus said:
Thank you for the encouragement guys
Thinking about things more, It needs to be 1992 or prior as I don't want to have to run cats; performance and sound wise.
I quite like the Pre HE cars, but I think realistically a good HE might be the best bet and with the most cars to choose from.
I also found this (look at the price but wow!)
https://store.jenvey.co.uk/jaguar-v12-e ... ckjr04-kit
Whether that would fit under the low bonnet of the XJS I'm not sure, but imagine the sound a throttle response!
Simply Performance have a demo car so once I have sold my other car I'm going to go and have a look at that to give me an idea.
_I'm a little all over the place at the moment as the range is so broad, but the options seem to be_
Bag a nice He 5.3, actually prefer the interior of earlier ones, for example, I've spotted a nice 1982 one for sale.
XJR-S 5.3 - I actually quite like the bodykit.
XJR-S 6.0 Pre Facelift Attracted by the 6.0 engine but scarce and the price etc. Difficult to repair Zytek engine management, probably would replace anyway.
XJR-S 6.0 1992/3 Facelift - A couple that look good value but I don't like the rear lights as much and they look like the heaviest version.
Also what is the actual cut off for running a car with no cat's legally?
I thought it was 1992? Would a facelift 6.0 be legal with no cats?
Confusing things is whether you "pass an emissions test" with cats or not.
You'll probably get more for your money by buying a HE car rather than pre HE to be honest, and a later HE too as they get a revised bonnet with more of a bulge that gives you a little more under bonnet clearance. You could always find an earlier interior if you really wanted, I agree they look better. Thinking about things more, It needs to be 1992 or prior as I don't want to have to run cats; performance and sound wise.
I quite like the Pre HE cars, but I think realistically a good HE might be the best bet and with the most cars to choose from.
I also found this (look at the price but wow!)
https://store.jenvey.co.uk/jaguar-v12-e ... ckjr04-kit
Whether that would fit under the low bonnet of the XJS I'm not sure, but imagine the sound a throttle response!
Simply Performance have a demo car so once I have sold my other car I'm going to go and have a look at that to give me an idea.
_I'm a little all over the place at the moment as the range is so broad, but the options seem to be_
Bag a nice He 5.3, actually prefer the interior of earlier ones, for example, I've spotted a nice 1982 one for sale.
XJR-S 5.3 - I actually quite like the bodykit.
XJR-S 6.0 Pre Facelift Attracted by the 6.0 engine but scarce and the price etc. Difficult to repair Zytek engine management, probably would replace anyway.
XJR-S 6.0 1992/3 Facelift - A couple that look good value but I don't like the rear lights as much and they look like the heaviest version.
Also what is the actual cut off for running a car with no cat's legally?
I thought it was 1992? Would a facelift 6.0 be legal with no cats?
Confusing things is whether you "pass an emissions test" with cats or not.
The link doesn't work but I think I know what you're referring to, and yes it does look fun! I'd love to compare a 5.3 with that against my 6.5 car. Yes it is tough to find a 6.0 RS but there is an overpriced one for sale at the moment, but there are definitely 5.3 RS cars cropping up now and again as projects.
Throttle Body Kit etc
https://store.jenvey.co.uk/jaguar-v12-e-type-sf45-...
You have a 6.5l? Bored or stroked? Sounds expensive!
There is a 7L Lister for sale at the moment for £45K, it's not the usual wide body type with supercharger.
https://www.ebay.co.uk/itm/Jaguar-XJS-Lister/16356...
f:0 sjc said:
urquattroGus said:
There is a 7L Lister for sale at the moment for £45K, it's not the usual wide body type with supercharger.
https://www.ebay.co.uk/itm/Jaguar-XJS-Lister/16356...f:0
15 grand more on their website than the classified advert on Ebay!https://www.ebay.co.uk/itm/Jaguar-XJS-Lister/16356...
f:0 Latest online temptation is a British racing Green Sept 1992 "Facelift" XJR-S 6.0 but the drawbacks might be the weight of the facelift car and the fact I think I would still need to run cats....
The pre facelift XJR-S looks better from the back but the facelift one does have a few things going for it maybe...
Edited by urquattroGus on Thursday 28th February 16:06
lukeharding said:
urquattroGus said:
Bought for £40K at auction in November 2018
Latest online temptation is a British racing Green Sept 1992 "Facelift" XJR-S 6.0 but the drawbacks might be the weight of the facelift car and the fact I think I would still need to run cats....
The pre facelift XJR-S looks better from the back but the facelift one does have a few things going for it maybe...
Thats the Historics one right? It failed to sell on the day, but might have sold afterward. I know the owner (not very well, admittedly) and was curious when I saw it for sale with a dealer. Latest online temptation is a British racing Green Sept 1992 "Facelift" XJR-S 6.0 but the drawbacks might be the weight of the facelift car and the fact I think I would still need to run cats....
The pre facelift XJR-S looks better from the back but the facelift one does have a few things going for it maybe...
Edited by urquattroGus on Thursday 28th February 16:06
The historics one was a Japanese market 1993 5.3 that had been converted to manual, XJR R1 wheels etc. Looked interesting. DO you know much more about it? Think this is the one you mean??
melhookv12 said:
Gus. I have a 6.0 litre genuine XJRS for sale.
I've converted numerous v12's to manual.
Using Jaguar 4 speed with mods. Cos worth 5 speed.
Converted earlier cars to outboard rear brakes also.
I've had 7.0 litre lister engine, with 6 downdraft webbers.
We've raced about 3 xjs' so I know my way around them.
Let me know if interested in buying the car. It will come with my phone number so you can ask me any questions along the way.
Thanks, I've emailed you via PH.I've converted numerous v12's to manual.
Using Jaguar 4 speed with mods. Cos worth 5 speed.
Converted earlier cars to outboard rear brakes also.
I've had 7.0 litre lister engine, with 6 downdraft webbers.
We've raced about 3 xjs' so I know my way around them.
Let me know if interested in buying the car. It will come with my phone number so you can ask me any questions along the way.
I think it’s best to stick to something like emerald or Omex.
Omex supply KWE whom do a ECU set for about 5k.
No doubt this means ordering from an Omex dealer would be fairly straightforward.
I fitted Omex to my Alfa by ordering the kit and loom from a local supplier and fitting it myself. Then got the supplier to map it. Supplier was At Speed Racing at Rayleigh, they were good.
If you go for a more obscure ECU then there might be less support and know how out there. Of course there is always Motec and others but they might be overkill.
Omex supply KWE whom do a ECU set for about 5k.
No doubt this means ordering from an Omex dealer would be fairly straightforward.
I fitted Omex to my Alfa by ordering the kit and loom from a local supplier and fitting it myself. Then got the supplier to map it. Supplier was At Speed Racing at Rayleigh, they were good.
If you go for a more obscure ECU then there might be less support and know how out there. Of course there is always Motec and others but they might be overkill.
This might be back on.
I've been to look at an '89 5.3 XJS with Marelli Ignition.
The car was already converted to manual using the Getrag 265 and appropriate rear diff.
Got a chance to drive it and it felt pretty good. AJ6 Exhaust and uprated dampers, springs and ARB. TWR bodykit etc.
It seemed to be in good condition underneath when on the ramp, lots of new parts, however most work done about 10 years ago and hardly used since.
Found a small amount of water in the passenger footwell but not rust holes, seems like a lot of XJS do leak?!
Anyway, for circa 14K it's tempting.
The thing is, I haven't driven an auto yet, particularly the facelift 6.0 XJRS that I fancied....
The manual car is nice but it's a standard HE with lots of mods (most of which i would do myself)
However, I can't help but wonder If I should pay more for a 6.0 XJRS or XJR-S and then convert to manual.
Might piss the purists off, and then would prob have to replace the Zytek engine manament on an XJR-S.
For both cars I fancy fitting emerald/omex and throttle bodies.
Is the 5.3 HE very Tunable? The Jaguarsport 6.0 has different internals etc.
Decisions decisions.
Part of me says buy the older 5.3 and finish it off, enjoy driving it hard, most of the expensive stuff such as box has been done.
The other part says buy a 6.0 as more special but I know that means more money to get a good one and less originality.
hmmm.....
I've been to look at an '89 5.3 XJS with Marelli Ignition.
The car was already converted to manual using the Getrag 265 and appropriate rear diff.
Got a chance to drive it and it felt pretty good. AJ6 Exhaust and uprated dampers, springs and ARB. TWR bodykit etc.
It seemed to be in good condition underneath when on the ramp, lots of new parts, however most work done about 10 years ago and hardly used since.
Found a small amount of water in the passenger footwell but not rust holes, seems like a lot of XJS do leak?!
Anyway, for circa 14K it's tempting.
The thing is, I haven't driven an auto yet, particularly the facelift 6.0 XJRS that I fancied....
The manual car is nice but it's a standard HE with lots of mods (most of which i would do myself)
However, I can't help but wonder If I should pay more for a 6.0 XJRS or XJR-S and then convert to manual.
Might piss the purists off, and then would prob have to replace the Zytek engine manament on an XJR-S.
For both cars I fancy fitting emerald/omex and throttle bodies.
Is the 5.3 HE very Tunable? The Jaguarsport 6.0 has different internals etc.
Decisions decisions.
Part of me says buy the older 5.3 and finish it off, enjoy driving it hard, most of the expensive stuff such as box has been done.
The other part says buy a 6.0 as more special but I know that means more money to get a good one and less originality.
hmmm.....
Agreed, I went to see ben at Simply performance and event had a drive in a manual 5.3 that he was just putting up for sale at the time. I was sorely tempted and it drove well. I still want to do this project but in the end I bought a Z3M Coupe instead, Botha ere vying for my affections. Haven’t itched the V12 Jag itch yet!
There was a 1994/5 XJS that has been converted to XJR driveline doing the rounds, done to a high standard and featured in one of the Jag magazines, seen another less shiny one too.
There is also that nice looking one off DB7 which Tom Walkinshaw had made with the Jag V12 before the Ford derived V12.
There is also that nice looking one off DB7 which Tom Walkinshaw had made with the Jag V12 before the Ford derived V12.
OTT532 said:
Well it took a little longer than I wanted to get all the bits together. Tom Lenthal now has the car and the auto box is out. Of course we have found a small number of additional jobs that are easier done while the car is in bits. Hopefully the 5 speed will be in early next week. I took the opportunity to replace all the wood trim with a dark Wenge veneer, by Classical Dash in Stokenchurch. I wanted something totally different and I am very pleased with the result.
The next job is a hand built Stainless steel exhaust from Haywood and Scott in Essex. That's booked in for August 17th. Then when the weather runs out and Autumn starts I will be doing the body work. Although this car has £37K receipts from KWE only 15k miles ago it has been 10 years and one particular wheel arch was filled instead of replaced with new metal. So that and a number of nicks and small blemishes mean a full restoration is going to be done.
Then I will have a V12 totally rust free, pre face lift 5 speed XJS with a sports exhaust. That is exactly what I set out to achieve.
Awesome! KWE do look like they can charge huge amounts! The next job is a hand built Stainless steel exhaust from Haywood and Scott in Essex. That's booked in for August 17th. Then when the weather runs out and Autumn starts I will be doing the body work. Although this car has £37K receipts from KWE only 15k miles ago it has been 10 years and one particular wheel arch was filled instead of replaced with new metal. So that and a number of nicks and small blemishes mean a full restoration is going to be done.
Then I will have a V12 totally rust free, pre face lift 5 speed XJS with a sports exhaust. That is exactly what I set out to achieve.
Just to say that this dream still very much lives on
I'm enjoying the BMW M Coupe I bought instead too much to just chop that straight in, but there's got to be a way!!
Now building an extension which slows matters down again.
Has anyone any updates on XJS manual V12 projects to whet my appetite?
I'm enjoying the BMW M Coupe I bought instead too much to just chop that straight in, but there's got to be a way!!
Now building an extension which slows matters down again.
Has anyone any updates on XJS manual V12 projects to whet my appetite?
Edited by urquattroGus on Friday 4th June 20:11
Nice to see I'm not the only one interested in this
Simply Performance in the UK were very helpful with manual swap stuff, worth speaking to them maybe?
I drove a manually converted car and wish I'd bought it
Dark Blue 5.3 HE with TWR bodykit and DB7 suspension and brake upgrades, drove really well.
6ltr wise there is the XJR-S or XJRS 6.0 which I think has the same bolt pattern as the 5.3, and then the later 1993/4 on 6.0 with coil pack ignition that was mated to the GM 4 speed auto box instead of the older 3 auto speed box.
Simply Performance in the UK were very helpful with manual swap stuff, worth speaking to them maybe?
I drove a manually converted car and wish I'd bought it
Dark Blue 5.3 HE with TWR bodykit and DB7 suspension and brake upgrades, drove really well.6ltr wise there is the XJR-S or XJRS 6.0 which I think has the same bolt pattern as the 5.3, and then the later 1993/4 on 6.0 with coil pack ignition that was mated to the GM 4 speed auto box instead of the older 3 auto speed box.
RobXjcoupe said:
https://www.ebay.co.uk/itm/185539305106?mkcid=16&a...
I know it’s not a v12 but still an interesting spec and manual
Yes, been eyeballing that, although MOT history points to quite a few rust issues. I know it’s not a v12 but still an interesting spec and manual
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