Adjusting Valve Stem Length

Hi guys,

I've built some engines but this is the first time a manufacturer tell me that I need to cut a valve in order to add a fix valve shim 1.35 mm and match the valve clearance with the cam follower because they only make them in one size (which is pretty bad). So the question is, how would be the best way to cut them and what tool do you use for that considering I already measure all the clearances and adding 1.35 mm I already know how much I need to cut on each one of them.

Also, I would like to know your opinions about reusing a head gasket that the car hasn't started since this is going to be the first time I need to remove the head from an engine I'm building. I will never leave this task for the end (measuring valve clearance) anymore :(

Thanks guys.

If you need to shorten a valve then this is a task that would be completed by your engine machine shop. The problem with shortening the valves is that you will end up grinding through the hardening and you can end up with a valve tip that will wear. This is very dependent on the type of valve actuation and you can deal with this by using hardened lash caps on the top of the valve stem (I did this on my old 4G63 drag engine since we were using custom valves).

If the engine hasn't run then the head gasket should be reusable. In some cases if you're using a factory composite style gasket it can stick to the head or block surface and be damaged on removal in which case you'll need to replace it. If you're using an MLS gasket it shouldn't be an issue.

Hi Andre,

I'll be using Supertech valves, spring kit, cam followers and valve shims (which are recommended by them), the valve actuation is direct. I called them and they say "it's okay to cut the valve as much as you need it according to the valve clearance you're looking for then add a fix shim size 1.35 mm".

It's for a Ford Focus 2.3L RS Ecoboost, have you worked on any of these engines? do you still recommend to buy the lash caps for the top of the valves which also come in many sizes?

Thanks again.