[Tjac]

My dad has 2 86 XJS H.E Roach Jaguars. Now he belives that these Jags have that Rare Jaguar Racing IRS system. Does anyone know about these IRS's. Maybe on how can I identify this rare IRS and if it's any good maybe someone would know what I need to use this on the ffr?

[ November 08, 2002, 04:08 PM: Message edited by: Tjac ]

 

[Robert Duncan]

Don't think they are particularly rare. You would need an engineering degree to put one in an FFR. It is way too wide, needs cut down.

It is a system that uses a rigid half shaft as the top lateral locating member. Old technology, the T-bird derived system is much more modern.

It is not very effective without a somewhat long track rod, difficult to package in an FFR. They are also very expensive to rebuild and re-gear, never heard of an XJS that had a positraction, so that adds another $5-800.

 

[Tjac]

Great, I didn't really want to put it on there either, how does it preform on the track ?

 

[William Mapstone]

The 12 cylinder Jags DO have posi-traction, the 6 cylinder Jags usually DO NOT.

Are these "Jag Race IRS Systems" different than the IRS that jag has been using from 1968 to the 1990's in their XJ6, XJ12, and XJS?

If they are different than they may be decent performers, although don't waste your time trying to convert to an FFR.

If I am not mistaken, one of the Smith brothers bought a Race bred Jaguar XJS.

 

[Tjac]

I think these are both stock from the factory, I do know they are huge huge 12 cylinders.I wonder if I could put that in the FRR , didn't Superproformence put Viper Engines in the FFR ?

[ November 08, 2002, 04:33 PM: Message edited by: Tjac ]

 

[William Mapstone]

If it is a stock Jag IRS then as Robert stated they are inferior in design. But since your jag has a 12 cyliner engine, then it is posi-traction and is worth more to some of the other non FFR cobra guys.

 

[Tjac]

Does anyone know if I could put that 12 cyl in the FFR, or do I need to put under a new thread ?

 

[cobramd]

Tjac Why would you want to. The motor really belongs in an ocean liner not a car. Its big heavy and the heads dont flow good enough to make big HP. The 6 cylinder motors were more of a race motor and could make serious HP if properly aspirated. If you really want a Jag powerplant use a Eaton Sc V8 its all alloy and can be easily pushed into the mid 400's for HP.

 

[Tjac]

ya, I was thinking anyways snice the car is so light that much horsepower would cost to much in tires