XK140 3.4 Valve Stem Height

I am reworking a head fro a 1957 XK140, 3.4
The valve seats look to have been re cut several times already.
I am concerned that they are now to deep and I will not be able to get the correct valve clearance.
Does some one know the correct valve stem height from the valve spring base to the tip of the valve?

If you can’t get the clearance use Jaguar X300 buckets which give you loads of extra clearance to play with.
You may even have to use extra thick shims which are also available.
Got mine from Ken Jenkins who is in the UK.
No need to resort to grinding the ends of the valve stems which often ends in tears.
Buckets are around £16 each, thicker shims about £3 each. Had to do this on my Mk9 last year

I appreciate the response.
Thank You

But I need that particular dimension for machine purposes to locate the new seat depth.

Daryl W Wagner

Automotive Artistry


IIRC, at proper depth, between the valve and the base circle of the cam is 0.0320".

Just had a discussion about this a few weeks ago.

Use a depth mic across the cam cover mating surface to the valve stem. Look for .850 ± .015

If you want to fit the small side of middle range shims you want to be at the .320" stem to cam base circle as Wiggy said. If you can measure the clearance… you can calculate with that math stuff if you will fall out of the available shim range. Poor performance aside, you have to find oversize shims. If you are outside the Jag shim range the correct remedy is new valve seats. And probably guides…and why not put in the bigger intake valve from the later XJ’s.

See how I spend your money!

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I want to say thank you to those that responded.
I appreciate the information.