What do I have?
What are specs of the cams? Stock?
HE Heads?
Forged pistons?
11:1?
Thanx,
Richard Wright
55 years of Jaguars




Allan Scoot, did you build these engines?

 

without closer inspections, it looks like that head has been surfaced/milled flat on the top of casting!
unusual thing to do , i wonder what the purpose would be?
also looks like the plugs come straight out, NOT angled?
ron

 

That is an HE head, I am pretty sure. What is inside, goodness knows! If the build date is correct, then JaguarSport was by then a Jaguar-TWR joint business, after the time TWR was modifying engines on its own account. The first few V12 JaguarSport cars (maybe 300) had 5.3 litre engines and various body mods, they were introduced in March 1989. The 6 litre cars were offered a few months later, so your engine might be an early 6 litre one, or might not, the 6 litre XJR-Ss were introduced in August 1989. The best way to check is to measure the stroke with a wire down a plug hole. The stroke should be 78.5mm if a 6 litre engine, 70mm if a 5.3. In either case the CR will be 11.5:1, all V12s after about 1988 were.
These facts are taken from NIgel Thorley's excellent book: You and your Jaguar XJS publlished by Haynes.

 

Richard hello--this group is super knowledgeable and helpful! Cheers https://www.facebook.com/groups/xjrs...?ref=bookmarks

The Coventry Foundation was just presented with XJR-S #58. Which is why we sought their knowledge!

 

Richard,

As others have mentioned, that seems to be a standard JaguarSport 6 litre engine, not a TWR-enhanced engine. In which case, it has the lengthened 78.5mm stroke and 11.2:1 compression.

They do look lovely when they are stripped down without all the fuel injection pipes!

Cheers

Paul