OzVMX Forum

Clubroom => Tech Talk => Topic started by: cappra on August 21, 2010, 05:36:12 pm

Title: Teflon coated pistons
Post by: cappra on August 21, 2010, 05:36:12 pm

Need opinions pro's and con's on getting pistons teflon coated.
Have had zero experience with piston coatings.
                                                                     Thanks, Jared

Title: Re: Teflon coated pistons
Post by: hitatreeonce on August 21, 2010, 07:02:39 pm

I wouldn't buy one , just sounds dodgie to me

Title: Re: Teflon coated pistons
Post by: BAHNZY on August 21, 2010, 07:53:58 pm

A lot of pistons come with the the black teflon CERAMIC coating from new, Woosner is one that comes to mind. Where we have a bore that is marginal needing to go to the next oversize, we will teflon CERAMIC coat the piston and get another season out of it.
On any of the 500's that we built for the rigours of FINKE, it was almost mandatory.
It's no gimmick, we use it pretty much all the time.

Title: Re: Teflon coated pistons
Post by: bigk on August 21, 2010, 09:17:37 pm

Had some slighty worn pistons ceramic coated as well. Brings them back to spec and gives another lease of life to hard to source pistons.
K

Title: Re: Teflon coated pistons
Post by: dalesween on August 21, 2010, 09:45:00 pm

Back in about 84 i read an article in ADB where Geoff Eldridge applied some Kal Guard teflon coating to his KDX 200 pistons,raved about the stuff.

Dale.

Title: Re: Teflon coated pistons
Post by: BAHNZY on August 21, 2010, 09:45:08 pm

Correction
Mick is correct, Ceramic Coating, not TEFLON coating.

Title: Re: Teflon coated pistons
Post by: dalesween on August 21, 2010, 09:58:36 pm

I dont know about ceramic but i take that is baked on from the factory where the Kal Guard was a brush on additive.

Dale.

Title: Re: Teflon coated pistons
Post by: Lozza on August 21, 2010, 11:08:02 pm

Coatings on pistons are usualy microns thick so I dunno how that is going to get it back to spec? On any engine tuned to anywhere near it's potential the coating wears off anyway...........................

Title: Re: Teflon coated pistons
Post by: micks on August 22, 2010, 12:02:10 am

seen a piston with both cermic on the crown (white),teflon on skirt (black).pistion was from a air cooled road race bike. the owner said it worked but that was in a motor that would get pulled down after a meeting it was a hand granade.he had cermic coating in the exhaust port to keep heat out off the barrel.he had it done i think by hpc.

Title: Re: Teflon coated pistons
Post by: BultacoMacca on August 22, 2010, 12:36:36 am

I've had my Bully piston done by HPC Coatings in Victoria for two race seasons now. Took it out today and its not bad, coating worn off of the skirt bottom, not the sides. As Lozza says, it only gets you maybe a thou' thickness extra.

Title: Re: Teflon coated pistons
Post by: Lozza on August 22, 2010, 09:24:26 am

Coatings on piston crowns create detonation.

Title: Re: Teflon coated pistons
Post by: BAHNZY on August 22, 2010, 09:40:15 am

Never seen coatings above the ring lands, always below the bottom ring land.

Title: Re: Teflon coated pistons
Post by: LWC82PE on August 22, 2010, 01:21:03 pm

Yeah it used to be all the rage to get the top of the dome ceramic coated or something like that.