BC

https://rennlist.com/forums/showthre...46#post3652646

See my post. Are we done, wrt non-sleeved motors and non-nikasiled motors? PC-9 is supposed to hold up? All the voodoo gone?

I can get a set of JEs for around 1k. The coating is 500 or so for 8 (top and sides - I already did this with my stock pistons for another motor)

BC

*Whistles* Don't all respond at once people.

Stan.Shaw@Excell.Net

Maybe I am not the only ignoramous that doesn't understand your question....

BC

Sometimes I get ahead of myself. I guess its not a question. Is its a statement of amazement? distrust? This would make life much simpler if it lasts?

mark kibort

what is the type of coating that is on an stock Mahle piston for our 928s?

Tony

Tin

BC

Tony has spent enough time with these pistons to know too.

Most the tin has been on the pistons I have taken out of well-working engines. That obviously can change, but that is my perception.

svp928

The coating on stock pistons is actually iron plating.
I have no experience with Swaintech, but they might give you a referal to someone who has used it successfully...

Steve

BC

Hey Steve. The iron or sometimes tin coating on the pistons has always been thought of as a sacrificial coating. For break in. It is always in very good shape when I have taken engines apart. I bought a new-old stock set of 4.5L pistons once for an engine build, Mahle pistons. It looked like a different ferrous then what I have seen most of the time. The color may change though from age in the engine. I have had stock pistons coated with the PC-9, but not much of the original "ferrous" coating was take off to do that.

You can also get a "heavier" build up of the PC-9 if you choose to from swaintech. This can take up some extra room if you want to use your original pistons in a high mileage rebuild where the bore needs more cleanup. Notice Lindsey racing says they sell .003 upsized pistons - this much material can be taken off when the alusil has some scratches and you have someone "clean up" the bore with the final stage felt pads.

BC

I just talked to I think Mike at Lindsey racing. They are in OK, and he says that they have been running regular Wiseco 4032 forged pistons, and will try the 20xx series metal as well. The simply coat the sides by Swain with the PC-9, and it has lasted in thier engine for like 10,000 miles. They took them out last winter and they were barely worn....

I personally think this is a very big deal. I guess nobody else does, and wishes to continue paying extreme amounts of money for either a nikasil bore (and these pistons, which would be coated again anyway), or to spend 1000s of dollars on Mahle pistons which don't seems to be up to snuff any more anyway.

Bigger bore and boost? Obviously requires a sleeve, and its being done as a normal thing now in WI, and by a few 944 turbo guys.

But for moderate boost on a less-expensive engine build, with stock bores, or ones that have a bit taken off them to really clean them up, why not?