I just got a "possible" 4040 Valve in the mail today but I can't seem to find the actual designation numbers, i.e. 2040, 3040, or 4040 anywhere on the valve. If anyone could explain in detail where this number is located or has a picture of where it is on the valve I would greatly appreciate it

 

Any ideas?

 

It should be on the middle of the prop valve. The 17/25 prop code from my 89 si is in the same location as my da 4040 prop valve.

 

Yes in "the middle" where the top part join the bottom. it is small and shallow marks. but not hard to find.