xk heads/intakes

i'm in the process of putting together 2 heads from boxes of parts.
one engine was from a 120, the other a 140.
i'm trying to figure out which intake manifold goes on which head. based on the staining in the water jackets the following seems to be how they were installed before.
one manifold, c4953 appears to go on the c type 140 head.
the other is a,c7462. is this correct for a 120 or have they been previously swapped? the numbers are opposite form what i would have thought.
are they interchangable? they have definite differences in water outlets ,etc.
also is the parts manual what i need to id such items? i have the shop man but it has no part numbers.
thanks for your help.
david

Can you post pics? I have a friend who might be of help if you can post pics. (no promises, but I'll see what I can do).

Basil

I too have one of each...
c7462 came off the '57 MK7 engine (same vintage as XK140), and c4953 came on the '53 XK120. The main difference that I see is an additional vaccuum port on the bottom towards the rear of the later unit...

I expect that either would work fine, but I think c4953 is proper for your exkayonetwenty. Not sure what the extra vaccuum was for...but it ain't there on my 53 coupe.

And by the way....you have fine taste in cars! What's your chassis #?

Cheers,
Matt B
680895

Hey...questions such as David's give me an excuse to have a coffee/smoke break, and go to the basement and dig around in old Jag parts....much more fun than working....

Cheerio,
Matt

Originally posted by Matt B:
Hey...questions such as David's give me an excuse to have a coffee/smoke break, and go to the basement and dig around in old Jag parts....much more fun than working....

Cheerio,
Matt

Click to expand...

I can think of a lot of things that are more fun than working...but we won't go there

Basil

thanks for the info matt.
my chassis number is S681390.
can you provide any info as to the signifigance of the "S"?
and may i return the compliment re: taste in autos.
i'm brand new to the jag world but i fall more in love with her everyday!

Hmmm....not sure about the "s"...but I would suspect that it perhaps would designate your care as a "SE" or "MC"....which would have had a C head original, as well as wire wheels, possibly thicker torsion bars...and maybe some other goodies. Don't remember for sure. The first of the "C type" heads didn't have the "C" cast into the top of the block....they were only designated by the "S" as the last digit in the engine number....

I may well be wrong there though...I can't tell the difference between my "-8s" head, and the one from the MK7.

What is the original engine number?

If it ends in "-8S", then it would probably be an XK120MC (or SE depending on what country you are from).

Sorry I can't help much here...all my books are at my cabin where there is no internet. I'm pretty much over my head here though...you would be wise to contact folks more in the know. A good place to start would be Phillip Porter's "Original XK" book. There are two editions...the second is perhaps better, but if you can find both, get 'em. They have detailed breakdowns of almost every change...when they changed...etc. The second is still in print and should be available somewhere online or locally. THe first edition might be a little harder to find. They are both full of great pictures and go into great detail. Expect to pay about $30 each. Well worth it!

Got any pics of your car?

-Matt

Originally posted by Matt B:
I too have one of each...
c7462 came off the '57 MK7 engine (same vintage as XK140), and c4953 came on the '53 XK120. The main difference that I see is an additional vaccuum port on the bottom towards the rear of the later unit...

I expect that either would work fine, but I think c4953 is proper for your exkayonetwenty. Not sure what the extra vaccuum was for...but it ain't there on my 53 coupe.

And by the way....you have fine taste in cars! What's your chassis #?

Cheers,
Matt B
680895

Click to expand...

Thanks Matt! Wow, this is the kind of synergy I like!

Basil

matt,
the original engine number is F2179 8S.
i asume this is 8:1 compression with a C head? this is the engine i have in a crate right now.
i'll be putting the c head on a 140 engine. everything i've read so far suggests it should work fine.
if i can figure out where all the hoses go!
David
681390

i almost forgot, here's a link to a few poor quality pics of my baby.
https://www.jag-lovers.org/v.htm?993589443