Is it OK to use synthetic oil?

Hi all

I’m new to JL and wanted to introduce myself, though I’ve already sneaked in a couple of questions in on this site … ( thanks for your answers btw … I already crossed a vital hurdle by inserting a length of coaxial ignition wire )

I live in in southern Cal and own two XJS 5.3 HE’s … both 1985. I bought the first ( white one in pic ) in 2000, and at the time I didn’t really know too much about Jaguar V12. I was a lamb to the slaughter really; From the moment I saw the car I was totally sucked in by the fine lines and aesthetics of the low profile body. I was sold from the start and my questions were like afterthoughts. As I was about to tell the previous owner I’d buy it he seemed to hesitate like there was something I should know “errrmm … I thhh-ink it might have been boiled over, " he said … " that’s right I remember now … it WAS boiled.” I didn’t think much about it really … I had owned cars that boiled over before.

The transaction was quickly done. little did I know what I was in for, but to quickly summarize I bought my second XJS in 2003 because the first had a warped head and ended up parked in the garage ( for 8 yrs ) with a couple of blown pistons and jammed rods. The engine wouldn’t wheel over without causing the whole car to rock, which gave me a feeling of bad karma. I also knew the cam shaft was probably be thrown out of true … this plus one of the catalytic converters had sprayed out of the exhaust along with a shower of molten piston beads … oil also poured out of the left air filter cover …I knew it was a mammoth job.

Over the next few months I visited many jag shops to see if they would pull the engine and do a rebuild. No luck. They all told me to keep it for a spare and buy another, which I thought was pretty extravagant and maybe a bit excessive. Then after a while I warmed up to the idea; There were plenty of XJS’s around and I lived in California where everything was excessive. That’s when I decided not to waste my life moping round and buy another. Ten months later I was on my way Hollywood to perhaps make another life changing mistake. On the way up I reasoned to myself that at least the mistake would be a classy one done in style. I felt great but it was something about Hollywood: this place of the silver screen and Oscar presentations, I was going there to buy an XJS!! The shiek cat I met in studio city did not disappoint; it was really an untouched, untampered with, very original car with 70k on the clock. Metallic claret with a saville grey interior, no cracks, perfect leather with no rips or split seams … at 17 yrs old the stitching was really perfect, even on the center arm rest … the vinyl dash was like new with no bridges in front of the instrument panel, a favorite place for disappointment … even now the burl elm fascia is still in unblemished condition with no swirls or glossy scratch marks from rough dusting rags.

Since then I’ve has the engine on my first car rebuilt which I’ll talk more about later … I did not do the rebuild