RE: Tuner tweaks for Jaguar XK
Monday 7th August 2006
Arden's take on the XKGerman tuner Arden has produced a set of modification kits for the Jaguar XK -- the first of its kind?
Tuner tweaks for Jaguar XK
Arden offers power, chassis, interior updates
Arden's take on the XK
The company's offering body mods, engine tuning with power increases from 300bhp to 380bhp through a special crankshaft, with forged and lighter pistons and connecting rods. The company adds what it calls an "optimised engine management strategy", plus high performance catalytic converters. Arden adds more and oil and more cooling through a new sump with cooling ribs and a 1.5 litre greater volume. Prices for tuning start at €4,466 (about £3,000).
Arden also provides a sports exhaust, lowered suspension, bigger brakes, wheels (21-inchers) and tyres, plus interior tweaks.
You'll need to call the company for quote -- and check that you couldn't get more power by buying an XKR at only £7,500 more than the XK.
Discussion
498 BHP.
Do you really mean "dyno figured" ?
Or do you mean "checked on a rolling road" ?
XKRs with auto gearboxes hate being rolling roaded. (In fact Jaguar SVO strongly advised us not to run XKRs on rolling roads). And don't forget that a rolling road can provide you with a wide range of "answers" depending on what the operator is aiming to achieve !
If you want to preserve the life of your personal XKR, get an accurate stopwatch (in the worst case) or a Racelogic V-Box (in the best case). Now check the car's full throttle acceleration - with D selected - from 40 to 140 mph BEFORE it is converted. Use a bone dry road, with a full fuel load and select Traction control off. Log the time and the distance for a couple or three runs in the same direction and note the temperature and humidity.
Get the conversion carried out and then repeat the exercise - on a day when the temperature and humidity are very similar. (And do it with the same octane rated fuel, and with a full fuel tank - as previously). If its a 4.2 litre car, formerly with 400 BHP, you should get some useful results from a 98 BHP power increase.
If you really believe you have 498 BHP, persuade someone who has a Corvette C6 Z06 to run alongside you. The Z06 has a genuine 505 BHP and weighs about 1500 kgs with one man and a full fuel tank. An XKR with one man and a full fuel load weighs about 1650 kgs. The Z06 is a manual so get your friend to use one gear only, say 4th.
If your 498 BHP XKR stays within 50yds of the Z06 by the time you get to 140 mph, I think you may have 498 BHP. If it doesn't, then you may not have 498 BHP.
Here are some other benchmark comparative figures:
If you check the gen at the back of Autocar, you will find that the best 0-60 time that they achieved for a 4.2 litre 6 speed XKR Coupe was 5.9 secs, and for a convertible 6.6 secs. These don't compare all that favourably with the
0-60 figure of 5.1 secs for the 4.0 litre 5 speed XKR convertible (press launch car ?) that Jaguar submitted to Autocar in June 1998 (theoretically 375 BHP). Interestingly, the SVO 4.0 litre Coupe (generally remembered as the XKR-R) achieved 0-60 in the slower time of 5.4 secs in Oct 1999. If I remember correctly, that had a manual gearbox and was thought to have about 450 BHP.
Just for the record, when Autocar roadtested the first Paramount XKR 4.0 litre 430 BHP Coupe at Millbrook (1 driver, full fuel tank, 1650 kgs), it achieved 0-60 mph in 4.9 secs. It only did it once and after that the intercoolers were too hot to repeat the figure, but the time had been achieved and it was therefore allowed and became the recorded fact.
At this point, I should declare an interest - in those days Keith Spencer and I were the guys who created and sold (respectively) the Paramount conversions. Now we fulfill those roles at Racing Green Cars.
Just as a matter of interest, there is another thread in the Pistonheads Jaguar forum which has comments on the Chasseur X300 Twin Turbo 450 Tornado. Somebody rather unkindly suggested Chasseur seemed to be recreating the XJ40. For the record, I conceived this Chasseur product after we had already built 43 Twin Turbo XJ40 Stealths. Turbo Technics, the company which was commissioned to create the Tornado engines was, and still is, run by the Turbo guru, Geoff Kershaw. At that time Keith Spencer ran Turbo Technics South and was Turbo Technics best development engineer. He built the prototype Turbo Technics Chasseur Tornado engine to Geoff's and his design with a couple of my suggestions incorporated. These engines were 6 cylinder in line 4.0 litre engines which were bored out to 4.2 litres and strengthened internally like a full race engine. They were effectively blue printed, were equipped with special liners that penetrated the cylinder head and were sealed using special gaskets and "Wells" Compression rings. In addition, they utilised twin hybrid turbos, twin induction systems and twin intercoolers. The Tornado engines achieved 485 BHP on the EDS dyno in Dagenham and were then down tuned for reliability to 450 BHP. They cost some £14000 at retail money as far as I recall.
I am not disputing the Paramount XKR V8s 498 BHP, just saying its not easy to achieve that kind of figure from a supercharged V8, and that it is not easy to verify it - unless the engine is actually run on a dynamometer. If the engine makes almost 500 BHP and is to remain "solid as a rock" in your ownership, I would expect it to cost the sort of figure I have mentioned. Oh, by the way, Arden's 4.6 Litre 485 BHP XKR engine - for which Racing Green are the UK agents - costs over £20,000 + VAT. This kind of power is not normally cheap !
Do you really mean "dyno figured" ?
Or do you mean "checked on a rolling road" ?
XKRs with auto gearboxes hate being rolling roaded. (In fact Jaguar SVO strongly advised us not to run XKRs on rolling roads). And don't forget that a rolling road can provide you with a wide range of "answers" depending on what the operator is aiming to achieve !
If you want to preserve the life of your personal XKR, get an accurate stopwatch (in the worst case) or a Racelogic V-Box (in the best case). Now check the car's full throttle acceleration - with D selected - from 40 to 140 mph BEFORE it is converted. Use a bone dry road, with a full fuel load and select Traction control off. Log the time and the distance for a couple or three runs in the same direction and note the temperature and humidity.
Get the conversion carried out and then repeat the exercise - on a day when the temperature and humidity are very similar. (And do it with the same octane rated fuel, and with a full fuel tank - as previously). If its a 4.2 litre car, formerly with 400 BHP, you should get some useful results from a 98 BHP power increase.
If you really believe you have 498 BHP, persuade someone who has a Corvette C6 Z06 to run alongside you. The Z06 has a genuine 505 BHP and weighs about 1500 kgs with one man and a full fuel tank. An XKR with one man and a full fuel load weighs about 1650 kgs. The Z06 is a manual so get your friend to use one gear only, say 4th.
If your 498 BHP XKR stays within 50yds of the Z06 by the time you get to 140 mph, I think you may have 498 BHP. If it doesn't, then you may not have 498 BHP.
Here are some other benchmark comparative figures:
If you check the gen at the back of Autocar, you will find that the best 0-60 time that they achieved for a 4.2 litre 6 speed XKR Coupe was 5.9 secs, and for a convertible 6.6 secs. These don't compare all that favourably with the
0-60 figure of 5.1 secs for the 4.0 litre 5 speed XKR convertible (press launch car ?) that Jaguar submitted to Autocar in June 1998 (theoretically 375 BHP). Interestingly, the SVO 4.0 litre Coupe (generally remembered as the XKR-R) achieved 0-60 in the slower time of 5.4 secs in Oct 1999. If I remember correctly, that had a manual gearbox and was thought to have about 450 BHP.
Just for the record, when Autocar roadtested the first Paramount XKR 4.0 litre 430 BHP Coupe at Millbrook (1 driver, full fuel tank, 1650 kgs), it achieved 0-60 mph in 4.9 secs. It only did it once and after that the intercoolers were too hot to repeat the figure, but the time had been achieved and it was therefore allowed and became the recorded fact.
At this point, I should declare an interest - in those days Keith Spencer and I were the guys who created and sold (respectively) the Paramount conversions. Now we fulfill those roles at Racing Green Cars.
Just as a matter of interest, there is another thread in the Pistonheads Jaguar forum which has comments on the Chasseur X300 Twin Turbo 450 Tornado. Somebody rather unkindly suggested Chasseur seemed to be recreating the XJ40. For the record, I conceived this Chasseur product after we had already built 43 Twin Turbo XJ40 Stealths. Turbo Technics, the company which was commissioned to create the Tornado engines was, and still is, run by the Turbo guru, Geoff Kershaw. At that time Keith Spencer ran Turbo Technics South and was Turbo Technics best development engineer. He built the prototype Turbo Technics Chasseur Tornado engine to Geoff's and his design with a couple of my suggestions incorporated. These engines were 6 cylinder in line 4.0 litre engines which were bored out to 4.2 litres and strengthened internally like a full race engine. They were effectively blue printed, were equipped with special liners that penetrated the cylinder head and were sealed using special gaskets and "Wells" Compression rings. In addition, they utilised twin hybrid turbos, twin induction systems and twin intercoolers. The Tornado engines achieved 485 BHP on the EDS dyno in Dagenham and were then down tuned for reliability to 450 BHP. They cost some £14000 at retail money as far as I recall.
I am not disputing the Paramount XKR V8s 498 BHP, just saying its not easy to achieve that kind of figure from a supercharged V8, and that it is not easy to verify it - unless the engine is actually run on a dynamometer. If the engine makes almost 500 BHP and is to remain "solid as a rock" in your ownership, I would expect it to cost the sort of figure I have mentioned. Oh, by the way, Arden's 4.6 Litre 485 BHP XKR engine - for which Racing Green are the UK agents - costs over £20,000 + VAT. This kind of power is not normally cheap !
Paramount claimed that these 498 HP are RWHP, not flywheel on www.xkec.co.uk/xkforum/viewtopic.php?t=5081 .As you need to be a member to read it, here is some text from he posts:
Question : What was the HP at the rear wheels ?
Answer Paramount : Yes at the wheels and available for use
Taking a drive train loss of about 15% that would mean about 573HP at the flywheel up from 365HP.
I do not know if this is realistic or not but it sounds unbelievable, so I asked if they can substantiate their claim (still waiting an answer).
Question : What was the HP at the rear wheels ?
Answer Paramount : Yes at the wheels and available for use
Taking a drive train loss of about 15% that would mean about 573HP at the flywheel up from 365HP.
I do not know if this is realistic or not but it sounds unbelievable, so I asked if they can substantiate their claim (still waiting an answer).
Edited by avos on Monday 14th August 07:35
Jagman said:
Just as a matter of interest, there is another thread in the Pistonheads Jaguar forum which has comments on the Chasseur X300 Twin Turbo 450 Tornado. Somebody rather unkindly suggested Chasseur seemed to be recreating the XJ40. For the record, I conceived this Chasseur product after we had already built 43 Twin Turbo XJ40 Stealths.
!
Sorry Chas, the first of the pictures on the eBay page makes the front end look squared off, particularly the front bumper and below look more like the XJ40 rather than the curvier X300. It could just be the pictures obviously I haven't seen the real car, unlike you. Some of the other pictures don't give the same impression.
Hi Ken,
No offence taken.
I am wondering where you could find better pics of a Tornado.
The best impression is probably conveyed in the film that was made of that actual car
when Jeremy Clarkson was driving it for Top Gear.
I don't know if you could access Top Gear archive footage ?
Does anyone know if that is possible ?
By the way, Ken, I like your XK150 !
With Best Regards
Chas
No offence taken.
I am wondering where you could find better pics of a Tornado.
The best impression is probably conveyed in the film that was made of that actual car
when Jeremy Clarkson was driving it for Top Gear.
I don't know if you could access Top Gear archive footage ?
Does anyone know if that is possible ?
By the way, Ken, I like your XK150 !
With Best Regards
Chas
Hi Ken,
No offence taken.
I am wondering where you could find better pics of a Tornado.
The best impression is probably conveyed in the film that was made of that actual car
when Jeremy Clarkson was driving it for Top Gear.
I don't know if you could access Top Gear archive footage ?
Does anyone know if that is possible ?
By the way, Ken, I like your XK150 !
With Best Regards
Chas
No offence taken.
I am wondering where you could find better pics of a Tornado.
The best impression is probably conveyed in the film that was made of that actual car
when Jeremy Clarkson was driving it for Top Gear.
I don't know if you could access Top Gear archive footage ?
Does anyone know if that is possible ?
By the way, Ken, I like your XK150 !
With Best Regards
Chas
Jagman said:
Hi Ken,
No offence taken.
I am wondering where you could find better pics of a Tornado.
The best impression is probably conveyed in the film that was made of that actual car
when Jeremy Clarkson was driving it for Top Gear.
I don't know if you could access Top Gear archive footage ?
Does anyone know if that is possible ?
No offence taken.
I am wondering where you could find better pics of a Tornado.
The best impression is probably conveyed in the film that was made of that actual car
when Jeremy Clarkson was driving it for Top Gear.
I don't know if you could access Top Gear archive footage ?
Does anyone know if that is possible ?
I don't know, they maybe available on uknova, if that still exists.
Jagman said:
By the way, Ken, I like your XK150 !
With Best Regards
Chas
I should hope so
You (or Peter anyway) sold it to me. You've probably seen my X300 as well, Chris has done someone work on her.
Cheers
Ken
Jagman:
Do you have any information on what boost pressures were used on the 450BHP Chasseur XJ40 cars?
I see some brochures on ebay.uk that talk about 7psi for the twin turbo Stealth versions so I must assume for the 450BHP versions it was much higher than that. Any ideas?
--
Steve
Do you have any information on what boost pressures were used on the 450BHP Chasseur XJ40 cars?
I see some brochures on ebay.uk that talk about 7psi for the twin turbo Stealth versions so I must assume for the 450BHP versions it was much higher than that. Any ideas?
--
Steve
Edited by StevenD57 on Wednesday 7th November 07:58
Interesting reading and reminds me of the claims of tuners from a few years ago. I remember one firm presenting to Jaguar such a conversion - and a very interesting meeting it was!
Apropos the XKR-R (or XKR+ as it was more correctly known within Jaguar) it was not in existence in 1999 and certainly didn't pull 450hp - that was saved for another vehicle some time later.
Apropos the XKR-R (or XKR+ as it was more correctly known within Jaguar) it was not in existence in 1999 and certainly didn't pull 450hp - that was saved for another vehicle some time later.
StevenD57 said:
Jagman:
Do you have any information on what boost pressures were used on the 450BHP Chasseur XJ40 cars?
I see some brochures on ebay.uk that talk about 7psi for the twin turbo Stealth versions so I must assume for the 450BHP versions it was much higher than that. Any ideas?
--
Steve
Haven't seen Jagman on here for almost a year. He's still about in the real world, he was in at Racing Green Cars when I popped in last Saturday.Do you have any information on what boost pressures were used on the 450BHP Chasseur XJ40 cars?
I see some brochures on ebay.uk that talk about 7psi for the twin turbo Stealth versions so I must assume for the 450BHP versions it was much higher than that. Any ideas?
--
Steve
Edited by StevenD57 on Wednesday 7th November 07:58
No they never ever came close to 498 bhp which obviously couldn't have been rwhp. I have seen some of their dynos, which didn't look normal in their curves, and these also included 30% drive train loss (so 498 bhp was more like 348 rwhp). Very unreliable dynos these where. PP have now their own dyno for some time, and probably have learned over time to use it, and now they are showing a bit more realistic numbers for 4.0/4.2 engines.
So I guess I am still the only one with 401 rwhp out there ;-)
So I guess I am still the only one with 401 rwhp out there ;-)
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