Although I regrettably lost it I was once had a huge portfolio of XJS advertising covering the entire 21 year run. It definitely tells a story.

I've sometimes wondered how the XJS image and market might have changed if the 6.0 engine.....which was a real powerhouse compared to the 5.3 version.....had been introduced sooner.

Cheers
DD

 

Doug the difference in power between the 5.3 and the 6.0 is not that huge, roughly 40 horsepower. What makes the power seem much greater is the final drive, and lower first gear.
That plus with the superior electronics it just feels bigger than it really is.

 

Not that 40 hp is nothing, but you're right.

When I posted I was thinking of the 6.0 'package', so to speak....although I didn't specifically mention it

Cheers
DD

 

its not the HP that we feel its the torque at the wheels that counts!
6.0 has much better torque , the 5.3 you gotta rev it hard to be competative!
on a race track comin off a corner give me the 6.0 anytime, by the time you got your 5.3 in to its useful power range , Damn hittin the brakes for next corner!
both around the same weight close equal cornering, 6.0 leaving 5.3 behind, using torque!, after a dozen laps ,NO contest!
get it real?

 

Back in 2010 I got a 6.0 and helped put it in a 1987 with the 2:88 rear end. There was improvement but not impressive. I had a 3:54 from a MK 10 we swapped in and now he felt some real power. The swap to a T5 had him smoking the tires at every chance he could.
Before that I built a race motor with .400 stroke and 93mm bore. 13-1 compression & A pair of Kent billet cams. They killed bottom end. And the stroke wasn’t enough to make up for it.
Luckily I was using a Seinz gear box And could keep the engine in that narrow power band which was absolutely awesome.
It was fun beating Big block Corvettes out of corners, they don’t expect that.
For just cruising around the stroke adds something but most of what people feel is the better gearing in the later gear box and final drive.
You’ve told me how much you enjoy your 5.3 with the transmission and final drive you have. From the pictures you’ve shown it’s pretty impressive.
I’m reasonably sure the 6.0 used the same cam lift and duration as the 5.3. Jaguar tended to use that lift and duration in virtually every engine. Since about the late 50’s.
A low first gear combined with a lower final drive ratio makes the car feel sporty.