When I replace the plastic breather gear in favor of a steel, I understand I have to shim it, so do I just measure the plastic gear with plastic spacer, minus the steel gear size and that will be my shim size ?

 

dont need to shim breather

 

Put the steel gear in place, put a straight edge accross the cam chest and measure the distance, then subtract the clearance and you have the size spacer you need. They are available in steel from the aftermarket.

 

I know everyone recommends replacing the plastic breather, but I disagree. Are you doing any other work in the cam case?

 

Contrary to what you would think the plastic breather tears the bore up more than a steel one. It allows metal particles to embed themselves into the plastic and then they gouge out the bore. Also there are three different plastic breathers, a six slot and a seven slot. If you are going to use a plastic breather in a '84 wet clutch-early 92 use the seven slot (25311-90 prefered or 25312-90) as they have a more advanced timing then the six slot. on later models, late '92-'99 use the 25310-82a. The third one is the one used in the early '84 dry clutch (2513-77b) and should be used as in that model. Hope this helps.