2.2S piston coatings
 

I found a set of mahle 2.2S pistons that are in spec but approaching the wear limit(per my machinist).Has anyone used modern coatings on used pistons to bring them closer to spec or are there other methods that can be used on the cylinders.I dont have the specific measurements now but will be getting them soon.This will be a 2.4 with 2.2s pistons using an aluminum case mod S cams and mfi. Steve

i have no idea about this actually i want information about piston uses. but i got little information on this. i will implement that.

I would think that if your pistons are at the wear limit the top piston ring land is also out of spec. No special coating can fix that. Hopefully the lands are OK and then coating the piston skirts is a good idea.

Thanks mark,I think the ring gap was fine but I see what you mean.What coatings have you heard about being used.

You could go the old route and knurl the side skirts.
Knurling increases the overall diameter of the piston and provides a better oiling surface at the same time.
Bob

There are quite a few piston coatings out there now. The only one I am familiar with is what JE pistons are offering. I think the most common coatings are the piston skirt coatings. JE offers two; the standard skirt coating that is basically a dry-film coating that will reduce friction and galling during break-in. The other one is called Tuff Skirt that is a lubricating anti-friction and anti-wear coating. I have ordered pistons with both but like the Tuff Skirt over the standard. If you are running very high compression then I would use a Thermal Barrier piston dome coating. There are lots of Pelican's that have used piston coatings and they will have their opinions too.