Hello all...

Can anyone tell me with confidence if the V12 springs are actually set at a different spring rate than the XJ6 or is the only difference spacers etc?

I am wanting to know if all XJ - Series cars have the same front springs or different types depending on engine.

Cheers
Craig

 

Greg in France, in the XJS section has heaps of spring data/facts from the factory.

He rarely comes in here, so I will throw a brick on his roof in a minute when he wakes up.

OR

Send him a PM, he rarely bites.

 

I can tell you for sure that the springs are the same and had the same part number: RTC2751
Greg

 

Thanks guys

 

Here's what I come up with for the Series III cars

3.4 engine RTC2130
3.4 with AC RTC2129
4.2 engine RTC2754
4.2 with AC RTC662 (replaced by RTC2751)
4.2 CDN/J/USA RTC2522 (replaced by RTC2751)
V12 engine RTC2521
V12 CDN/J/USA RTC2520 (replaced by RTC2752, replaced by JLM1449)
V12 (later) RTC2753 (replaced by JLM1449)
V12 (later, Japan) RTC2520 (replaced by RTC2752, replaced by JLM1449)

The 1726, 2753, 1449, 2752,and 2751 were also used on various V12 XJSs depending on year and market

I think that all these various original part numbers represented unique specs....but the differences were subtle enough that they could be rationalized into fewer part numbers. In theory, at least. Given the number of instances where replacement springs give incorrect ride height, I'm not entirely convinced. This issue is confounded by Jaguar's use of spacers "as required" to trim ride height.

Cheers
DD

 

Nice work Doug!

great info