4 Valve XK head

[a8hex]

While hunting down information about an unusual inlet manifold for an XK120 this morning I came across photos of a prototype 4 valve XK head. I'd read in the Andrew Whyte books about them thinking of making 3 valve heads in the early 50s but I'd not come across the 4 valve head.
The photos where in the latest edition of Philip Porters XK book.
Any else seen anything on these things?

[mph]

a8hex said:

While hunting down information about an unusual inlet manifold for an XK120 this morning I came across photos of a prototype 4 valve XK head. I'd read in the Andrew Whyte books about them thinking of making 3 valve heads in the early 50s but I'd not come across the 4 valve head.
The photos where in the latest edition of Philip Porters XK book.
Any else seen anything on these things?

I know a company that's working on a four valve head for the XK engine, but that's a new development.

Never seen a period one.

[Flying Phil]

I believe that the XJ13 V12 engine had four valve heads and that the V12 was developed from the 6 cylinder block so presumably those four valve heads may well have been also possibly fitted to the 6 cylinder engine?

EDIT I was mistaken - mixed up the "Quad Cam" for the V12, with the "Quad Valve" The XJ 13 was a two valve head.

Edited by Flying Phil on Tuesday 19th March 09:12

[a8hex]

Flying Phil said:

I believe that the XJ13 V12 engine had four valve heads and that the V12 was developed from the 6 cylinder block so presumably those four valve heads may well have been also possibly fitted to the 6 cylinder engine?

I exchanged emails with Mr XJ13 this morning, he'd not heard of it.

The pictures are on page 364 of Philip Porter's 3rd edition of "Original Jaguar XK", the third edition is significantly expanded compared with the 2nd.

[SV8Predator]

Are there no captions with these photos? No explanation whatsoever?

[a8hex]

On page 364 the middle right hand picture has the covering text:
Another fascinating piece of Jaguar history. In early '59 the engine development department at Jaguar began evaluating a four valve head

The the bottom left picture:
This shot of the four valve head for an XK engine shows the cast in Jaguar part number and the foundry's numbers, the WM prefix telling us it was cast by William Mills Ltd.

(the Jaguar casting number I guess is the XK2587 number, there are also various stamped letters and number)

Then on the facing page The top picture:
With Jaguar no longer competing in sports car racing as a team, there was less impetus to push the boundaries and the four valve head took a back seat. One downside was an increase in weight

[dinkel]

Which is the 1st production 4v head for Jaguar?

2v heads do sound better . . . imo.

[a8hex]

For production cars? I guess that would be the AJ16 straight 6 for the XJ40.

Interesting point about the noise. I wonder whether there is some reason why they should sound substantially different.

I like the noise a DFV makes