I have 4 different VVT mechanisms that fit to the intake cam. All four are different in a number of ways. Some of the differences are factory differences. Some differences appear to be modifications or deletes to the mechanisms. I was hoping that someone with experience with these mechanisms might be able to help guide me. I spoke with Mazda and they confirm a number of different revisions but were unable to provide any detail as to what the revisions were. Drawings have been impossible for me to find.
1. The first thing I noticed is some seem to have a plunger and spring and some do not. Some of the plungers are different sizes. All of the mechanisms I think have the form and structure to support the plunger and spring even though it isn't there.
a) Did some come stock without this plunger and spring?
If not and putting aside legality for the moment, it appears that the mechanism will work without this plunger. True?
c) It looks like the purpose of the plunger is to lock the mechanism prior to the right RPM is reached and the mechanism is engaged. Correct?
d) Possible advantages of not using the plunger and spring?
2. One of the mechanisms had no leaf springs or U shaped sealing bars.
a) Again it appears that they mechanism is able to function without these as it came off of a functioning car. True?
Possible advantages of these not being used?
c) Were there versions that didn't come with these?
Thanks in advance for your comments and thoughts.