Manual shift Jags
Discussion
Having been brought up with Jags around me I am bound to have been a Jaguar nut. The thing is that all of the Jags that have been in our family have had a manual gearbox. Some of the obvious ones like the Mark 2 3.8 with overdrive and the XK150, but also the series 1 XJ6 4.2 and XJ40 4.0, both of which had to be specially ordered.
I acquired (6 years ago) a manual XJR and can think of no better way to own such a fantastic car. She drives like a dream and is so easy to sling around in country lanes. I cannot help but think that Jaguars decision to only make the new XJR in auto is a duff one. Do we all have knee and hip problems or is it because the purchase cost is so huge it is only likely to be the 'more advanced in age' that will be able to afford one? For a sports saloon the Jag really needs to be manual, doesn't it? If you ever get a chance to buy an XJR in manual form, do it!
I acquired (6 years ago) a manual XJR and can think of no better way to own such a fantastic car. She drives like a dream and is so easy to sling around in country lanes. I cannot help but think that Jaguars decision to only make the new XJR in auto is a duff one. Do we all have knee and hip problems or is it because the purchase cost is so huge it is only likely to be the 'more advanced in age' that will be able to afford one? For a sports saloon the Jag really needs to be manual, doesn't it? If you ever get a chance to buy an XJR in manual form, do it!
Well whilst my XK150 is a manual, my XJ6 (X300 3.2 Sport) is an auto. For the R it might be different, but I couldn't imaging the XJ6 as a manual. I don't think it would suit the car at all.
As for sales, only a tiny percentage of X300 sales were manuals I believe. Second hand the dealer I bought mine from said they were just impossible to shift. There probably wasn't the demand to warent spending developement dosh on a manual version.
With the X308 XJR, the torque increase might have meant there were not many manual boxes available that could handle all that torque, lets face it, they had to source the auto box from MB! Aston (and a few others) used the Corvette LT5 manual box as the only thing around that was man enough for the job, but it wasn't exactly the most slick of changes. Mind you, I like the Moss box in the 150, so perhaps agricultural gear changes have their place
As for sales, only a tiny percentage of X300 sales were manuals I believe. Second hand the dealer I bought mine from said they were just impossible to shift. There probably wasn't the demand to warent spending developement dosh on a manual version.
With the X308 XJR, the torque increase might have meant there were not many manual boxes available that could handle all that torque, lets face it, they had to source the auto box from MB! Aston (and a few others) used the Corvette LT5 manual box as the only thing around that was man enough for the job, but it wasn't exactly the most slick of changes. Mind you, I like the Moss box in the 150, so perhaps agricultural gear changes have their place
It may also be that many owners live far from open country lanes and have to grind through city traffic. If you're in a big comfortable Jaguar with all the luxuries, I suspect the last thing you want to do in urban traffic is wear your left leg out and 'stir pudding'
I believe they call it the needs of the majority outweighing the needs of the few...
Also, the V8 XJR has so much torque that it's hard to see a manual offering any significant improvement over the auto, which is a 5-speeder anyway.
I can see the point in arguing that a sports model like the XJR should at least have a manual option but as most owners, through no fault of their own, will live far from country lanes and have to pound motorways and grind through town traffic, they are probably more than happy with the auto.
Mercedes powerful models and AMG's are all auto, and even die-hard manual BMW 'M' models are now going down the auto route in various forms.
Most driving today is a congested chore, so market forces dictate that the manufacturers provide their buyers 'dream car' with an appropiate transmission choice in order to sell cars and therefore remain in business.
A good, responsive auto is still fun around the lanes, and when the transmission is correctly matched to the engine characteristics the result is harmonious.
Manual transmissions that can cope with big-torque engines by nature have to be robust and, therefore, are rarely light and sweet shifting.
But yes, I can see the reason for wanting a manual transmission exclusively on the XJR models!
I believe they call it the needs of the majority outweighing the needs of the few...
Also, the V8 XJR has so much torque that it's hard to see a manual offering any significant improvement over the auto, which is a 5-speeder anyway.
I can see the point in arguing that a sports model like the XJR should at least have a manual option but as most owners, through no fault of their own, will live far from country lanes and have to pound motorways and grind through town traffic, they are probably more than happy with the auto.
Mercedes powerful models and AMG's are all auto, and even die-hard manual BMW 'M' models are now going down the auto route in various forms.
Most driving today is a congested chore, so market forces dictate that the manufacturers provide their buyers 'dream car' with an appropiate transmission choice in order to sell cars and therefore remain in business.
A good, responsive auto is still fun around the lanes, and when the transmission is correctly matched to the engine characteristics the result is harmonious.
Manual transmissions that can cope with big-torque engines by nature have to be robust and, therefore, are rarely light and sweet shifting.
But yes, I can see the reason for wanting a manual transmission exclusively on the XJR models!
I have a V8 XJR and at first I couldn't find a single occasion when I would have preferred a manual. However, I'm now struggling to justify the XJR on my drive as living with it is exposing the compromises...
As a luxury cruiser the ride isn't good enough and the engine isn't smooth enough (supercharger whine). As a sportscar it is supremely quick, loads of grip, well controlled body but let down by the auto 'box - the biggest issue being that it doesn't feel very sympathetic to the 'box to 'manually' down shift to give some engine braking - this in turn exposes the brakes as not being up to the job.
To get out of this quandry, I am considering reverting back to an XJ40 - but this time a 6.0 V12. Now that is a car built for an auto.
Oh, I shall also be requiring a proper sportscar (with a maunual) for my alter ego.
As a luxury cruiser the ride isn't good enough and the engine isn't smooth enough (supercharger whine). As a sportscar it is supremely quick, loads of grip, well controlled body but let down by the auto 'box - the biggest issue being that it doesn't feel very sympathetic to the 'box to 'manually' down shift to give some engine braking - this in turn exposes the brakes as not being up to the job.
To get out of this quandry, I am considering reverting back to an XJ40 - but this time a 6.0 V12. Now that is a car built for an auto.
Oh, I shall also be requiring a proper sportscar (with a maunual) for my alter ego.
groomi said:
As a luxury cruiser the ride isn't good enough and the engine isn't smooth enough (supercharger whine). As a sportscar it is supremely quick, loads of grip, well controlled body but let down by the auto 'box - the biggest issue being that it doesn't feel very sympathetic to the 'box to 'manually' down shift to give some engine braking - this in turn exposes the brakes as not being up to the job.
It makes a GREAT luxury sports cruiser though doesn't it
...edit for poor quoting abilities
>> Edited by Philhopkins on Monday 15th May 09:46
bad company said:
I would have thought that the XJR might come with sequential gearbox option. That is on the new XK so the technonology is there. Now that really would be very nice.
The new XK doesn't have a sequential gear box, it's got a good old fashioned auto box, it just lets you manually control it.
Hi Groomi,
I can heartily recommend the 6 litre V12/auto option. After years of BMW's I bought my first Jag about 6 weeks ago-a 1995 'N' reg X300 model Daimler Double Six auto, with the 6 litre V12 and 4-speed auto, and it's an awesomely smooth and refined combination.
Yes, it's only as fast as a 'regular' X308 Jag 4 litre V8/5 speed auto in the acceleration stakes, and a V8 XJR would leave it for dead, but it feels monumentally relaxed whilst doing it, and utterly effortless.
It has around the same acceleration times as my current 1993 BMW 540i V8, yet the big, torquey V12 has instant low-down pick-up when on the move, whereas the 'small' high-revving multivalve head of the German 4 litre V8 needs to be stoked and worked to deliver it's 286BHP.
The difference is torque spread-the V8's not-inconsiderable 295lbf/ft doesn't arrive until 4500rpm and it feels flat until then, even though it drives through a 5-speed auto and only has to shift 1650kg.
The Daimler V12's 355lbf/ft arrives much lower at a subterranean 2850rpm so, even though it only drives a 4-speed auto and has to shift much more weight at 1975kg, the mountain of low-down torque from the old 2-valve head with smallish inlet tracts causes the car to surge forward instantly and leaves the high-revving multi-valve head V8 engine gasping unless it's wound up to silly engine speeds.
Apologies for comparing my Jag V12 with a BMW V8 engine, but I've not driven the Jag V8, although noticed that on paper that the X308 Jag power train is virtually indentical to the BMW V8 power train, as in 4 litre V8's with 4 valve-per-cylinder heads both developing around 290BHP and 290lbf/ft, give or take a few units, and both having 5-speed autos, with approximately similar bodyweights to shift.
I suspect the 'small' 4 litre high-revving V8's would go well with a manual, although it's debatable whether the supercharged Jag V8 really needs a manual with so much torque on tap already.
The massive low-down grunt of the big V12 is ideally matched to an auto though, which is traditionally held back by the initial 'step off' where the engine runs up to the stall speed of the torque converter which is usually around 2000rpm. The very low torque peak of the big V12 is mostly where the torque converter needs it, hence the rapid 'step-off' of the V12.
Most small-engined autos get bogged down on step-off in this 2000rpm torque converter 'hole', whereas the manual driver can dial 4000rpm and sharply engage the clutch for a much more rapid step-off.
Although the 4-speed auto of the V12 seems archaic today, it works very well with the V12. The later 5-speed autos are better matched to the 'small' high-revving V8's with their higher torque peaks, which require a numerically lower 1st gear for good 'step-off', something the 5-speed auto is better at than the 4-speed.
Basically, it's important to match the engine chracteristics to the transmission characteristics for the most harmonious results. A big, high torque engine with excellent low-down torque will rarely feel sluggish and you can loose speed comfortably as it's so easy and effortless to build it back up again, regardless of which gear you're in.
It could be argued, I suppose, that the V8 Jag XJR has so much power that what exactly is going to be gained by having a manual gearbox anyway, and would the end result be noticeably better than the present auto combination, given the type of use that most owners are going to realistically subject their cars to?
Interesting thought though...
I can heartily recommend the 6 litre V12/auto option. After years of BMW's I bought my first Jag about 6 weeks ago-a 1995 'N' reg X300 model Daimler Double Six auto, with the 6 litre V12 and 4-speed auto, and it's an awesomely smooth and refined combination.
Yes, it's only as fast as a 'regular' X308 Jag 4 litre V8/5 speed auto in the acceleration stakes, and a V8 XJR would leave it for dead, but it feels monumentally relaxed whilst doing it, and utterly effortless.
It has around the same acceleration times as my current 1993 BMW 540i V8, yet the big, torquey V12 has instant low-down pick-up when on the move, whereas the 'small' high-revving multivalve head of the German 4 litre V8 needs to be stoked and worked to deliver it's 286BHP.
The difference is torque spread-the V8's not-inconsiderable 295lbf/ft doesn't arrive until 4500rpm and it feels flat until then, even though it drives through a 5-speed auto and only has to shift 1650kg.
The Daimler V12's 355lbf/ft arrives much lower at a subterranean 2850rpm so, even though it only drives a 4-speed auto and has to shift much more weight at 1975kg, the mountain of low-down torque from the old 2-valve head with smallish inlet tracts causes the car to surge forward instantly and leaves the high-revving multi-valve head V8 engine gasping unless it's wound up to silly engine speeds.
Apologies for comparing my Jag V12 with a BMW V8 engine, but I've not driven the Jag V8, although noticed that on paper that the X308 Jag power train is virtually indentical to the BMW V8 power train, as in 4 litre V8's with 4 valve-per-cylinder heads both developing around 290BHP and 290lbf/ft, give or take a few units, and both having 5-speed autos, with approximately similar bodyweights to shift.
I suspect the 'small' 4 litre high-revving V8's would go well with a manual, although it's debatable whether the supercharged Jag V8 really needs a manual with so much torque on tap already.
The massive low-down grunt of the big V12 is ideally matched to an auto though, which is traditionally held back by the initial 'step off' where the engine runs up to the stall speed of the torque converter which is usually around 2000rpm. The very low torque peak of the big V12 is mostly where the torque converter needs it, hence the rapid 'step-off' of the V12.
Most small-engined autos get bogged down on step-off in this 2000rpm torque converter 'hole', whereas the manual driver can dial 4000rpm and sharply engage the clutch for a much more rapid step-off.
Although the 4-speed auto of the V12 seems archaic today, it works very well with the V12. The later 5-speed autos are better matched to the 'small' high-revving V8's with their higher torque peaks, which require a numerically lower 1st gear for good 'step-off', something the 5-speed auto is better at than the 4-speed.
Basically, it's important to match the engine chracteristics to the transmission characteristics for the most harmonious results. A big, high torque engine with excellent low-down torque will rarely feel sluggish and you can loose speed comfortably as it's so easy and effortless to build it back up again, regardless of which gear you're in.
It could be argued, I suppose, that the V8 Jag XJR has so much power that what exactly is going to be gained by having a manual gearbox anyway, and would the end result be noticeably better than the present auto combination, given the type of use that most owners are going to realistically subject their cars to?
Interesting thought though...
I worked at Jaguar Powertrain some years ago and I never found the true reason why the V8 is/was never offered with a manual box. It is only now mated to a manual box in the current V8 Vantage. I can only assume that the reason was 1 or more of the following,
1) Demand didn't warrant the development costs.
2) The engine's crankshaft wasn't suitable for a manual box (it was iron, not steel).
3) An XKR with a manual box may have competed too much against the DB7, consequently the manual was less viable on that engine just for the saloon.
4) The driveability wasn't what Jaguar wanted to have in their cars.
It is worth noting that the V6 S-Type is available with a manual 'box but a V6 XJ6 isn't which may suggest that that decision was driven by demand.
For me, a manual XJR (6) in black is the most desirable car which I could afford (an '89 V8 Vantage or XJ220 way too pricey). There aren't too many manual XJRs about & I'd be interested to know if they are still difficult to shift. I'd certainly take one.
1) Demand didn't warrant the development costs.
2) The engine's crankshaft wasn't suitable for a manual box (it was iron, not steel).
3) An XKR with a manual box may have competed too much against the DB7, consequently the manual was less viable on that engine just for the saloon.
4) The driveability wasn't what Jaguar wanted to have in their cars.
It is worth noting that the V6 S-Type is available with a manual 'box but a V6 XJ6 isn't which may suggest that that decision was driven by demand.
For me, a manual XJR (6) in black is the most desirable car which I could afford (an '89 V8 Vantage or XJ220 way too pricey). There aren't too many manual XJRs about & I'd be interested to know if they are still difficult to shift. I'd certainly take one.
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