A Quaife designed Limited Slip Differential has recently been developed in conjunction with Tom Lenthall, Norman Durban and Racing Green Cars. This unit can only be obtained and fitted from Tom, RG and Viezu/Paramount Performance who are bound by an agreement of fixed price retail marketing. The unit can be supplied for DIY fitting if those attempting fitting the unit have the equipment and skill level to ensure the necessary gear and pre-load requirements. This is not amateur work.
Costs for supply and fit of this unit is around £1560 plus VAT. I make that about £1872!
The unit comes into its own when a rear wheel looses traction and power is applied to the wheel which still retains grip. Useful in exiting junctions and bends in slippery conditions, the LSD compliments the DSC system already fitted to modern cars. This LSD would be of particular benefit in extremely powerful examples of the Jaguar mark.
I`d fit one myself but I`ve run out of ready cash!
Mike K
Limited Slip Diff for X350, S-type & XK models.
X350 Co-ordinator
2004 XJR
2004 XJR
Re: Limited Slip Diff for X350, S-type & XK models.
Hi Mike, The Thornton Power Lock diff has been fitted to Jaguars for many years, these have dished steel discs which are squeezed together by the action of the differential. Just out of interest, does the diff assembly to which you refer act in the same way?
P
P
Re: Limited Slip Diff for X350, S-type & XK models.
I have one of thoes in my S Type R.
Limited Slip Quaife Tourque Bias Differential not quite sure of the mechanics of how it works, but the basic principal is that power is delivered until slip is detected, then power alternates from side to side under slipery conditions (chalenging the laws of physics in the case of supercharged engines) until traction is equal on both sides when normal service resumes. This is all hapens quickly enough to deceive the standard electronic traction control on my car, so the two systems work together.
Most importantly the ford derived traction control fitted with the standard live axle is not required under normal or spirited driving, but comes into play under extream conditions.
I was trying to think of the last time I knew it was there, the truth is I can't, occationally I will get a churp from the 275 mm rear tyres without any noticeable retarding of engine power and progress is un hindered.
Stark contrast from before the Quaife being fiited, when frequently the electronics
interfeared with the intended quick exit from a junction, leaving the car stuttering to gain any speed as the computer said "no"!
I remember when the STR was first released Tiff Needell test drove the car and two things stuck in my mind, he didnt like the supercharger wine, I love it! He berated the fact that it had a live rear axle. To demonstrate this he (presumably with traction control off) turned sharp under full throttle lighting up the inside rear tyre as it spun desperatly trying to keep pace with the outside tyre that had more ground to cover. That just didnt seem right to me!
The remedy came about by accident, my car had developed a whine from the rear end noticable under slow driving conditions. I spoke to Tom Lenthall about this when the car was in for a routine service and he reported that it could be the diff ,propshaft or gearbox bearing.
But dificult to tell exactly which. We would have to change things under the process of elimination.
I was keen to try the differential first and asked about fitting a Quaife ATB which he had fitted to XK8s. Sharp intake of breath.. ok streight forward on XKs and XJs but the STR has a considerabaly smaller casing, Just my luck! But Tom thought he could machine out the case to take the gearing, I left it with him and a few months later he phoned to say he had a differential with Quaife ATB fitted.
Long and short is it works and has done for the last 5 years, just the best mod for a supercharged car.
The wine turned out to be the prop shaft but the diff was such a success I didn't mind.
Bit of a ramble and not a 350 story, sorry guy's but if your traction control winds you up Quaife is the way to go. IMHO
Andre
Limited Slip Quaife Tourque Bias Differential not quite sure of the mechanics of how it works, but the basic principal is that power is delivered until slip is detected, then power alternates from side to side under slipery conditions (chalenging the laws of physics in the case of supercharged engines) until traction is equal on both sides when normal service resumes. This is all hapens quickly enough to deceive the standard electronic traction control on my car, so the two systems work together.
Most importantly the ford derived traction control fitted with the standard live axle is not required under normal or spirited driving, but comes into play under extream conditions.
I was trying to think of the last time I knew it was there, the truth is I can't, occationally I will get a churp from the 275 mm rear tyres without any noticeable retarding of engine power and progress is un hindered.
Stark contrast from before the Quaife being fiited, when frequently the electronics
interfeared with the intended quick exit from a junction, leaving the car stuttering to gain any speed as the computer said "no"!
I remember when the STR was first released Tiff Needell test drove the car and two things stuck in my mind, he didnt like the supercharger wine, I love it! He berated the fact that it had a live rear axle. To demonstrate this he (presumably with traction control off) turned sharp under full throttle lighting up the inside rear tyre as it spun desperatly trying to keep pace with the outside tyre that had more ground to cover. That just didnt seem right to me!
The remedy came about by accident, my car had developed a whine from the rear end noticable under slow driving conditions. I spoke to Tom Lenthall about this when the car was in for a routine service and he reported that it could be the diff ,propshaft or gearbox bearing.
But dificult to tell exactly which. We would have to change things under the process of elimination.
I was keen to try the differential first and asked about fitting a Quaife ATB which he had fitted to XK8s. Sharp intake of breath.. ok streight forward on XKs and XJs but the STR has a considerabaly smaller casing, Just my luck! But Tom thought he could machine out the case to take the gearing, I left it with him and a few months later he phoned to say he had a differential with Quaife ATB fitted.
Long and short is it works and has done for the last 5 years, just the best mod for a supercharged car.
The wine turned out to be the prop shaft but the diff was such a success I didn't mind.
Bit of a ramble and not a 350 story, sorry guy's but if your traction control winds you up Quaife is the way to go. IMHO
Andre
Re: Limited Slip Diff for X350, S-type & XK models.
A useful reply Andre from someone who has experience of the unit.
When you pulled away at Southsea, I did wonder how you managed to keep everything in control. It was a foul, wet day with conditions that showed just how useful an LSD can be. I think I need one! Time will tell.
the characteristic you described for your car sounds very similar to what happens on my 350 when trying to get out quickly on a roundabout or junction. I wonder if Tom can decrease the sensitivity of the standard DSC unit? Anyway, with him tomorrow so will have a chat with him about the DSC and the Quaife unit.
Mike
When you pulled away at Southsea, I did wonder how you managed to keep everything in control. It was a foul, wet day with conditions that showed just how useful an LSD can be. I think I need one! Time will tell.
the characteristic you described for your car sounds very similar to what happens on my 350 when trying to get out quickly on a roundabout or junction. I wonder if Tom can decrease the sensitivity of the standard DSC unit? Anyway, with him tomorrow so will have a chat with him about the DSC and the Quaife unit.
Mike
X350 Co-ordinator
2004 XJR
2004 XJR
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SCUTHY2002
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Re: Limited Slip Diff for X350, S-type & XK models.
I have taken the plunge and spent the day at Tom Lenthalls. I now have the Quaife LSD and also a re-map to try and make the most of all the power upgrades I have added over the last 12 months. I am very pleased with the LSD which seems to work well with the DSC. No more embarrassing wheel spin when pulling away from junctions and noticably making better use of the BHP thats available. Many thanks to TL for getting all done in a day while I waited.
Re: Limited Slip Diff for X350, S-type & XK models.
Tom and Gerald to the rescue. Top guys all at Tom`s. Highly recommended and an experience which is totally unique in the industry.
Glad you are pleased with the mods.
Mike K
Glad you are pleased with the mods.
Mike K
X350 Co-ordinator
2004 XJR
2004 XJR
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