Millennium Technology Porosity and Streaking in Nicasil coatings

[rsss396]

[video=youtube;kdM73pERV6Q]http://www.youtube.com/watch?v=kdM73pERV6Q[/video]

[C-Leigh Racing]

Dave, what do you think about dimples in the bore wall from the exhaust port roof up to TDC ?.
Kinda like a golf ball, but spaced farther apart from each other.
Maybe done with a cnc mill so all would be just alike. I know dimples & grooves on the piston would work, but got to wonder the effects on the cylinder wall.
For sure it would be places of no contact & reduce friction.
Neil

[rsss396]

I think the dimples on the piston skirt to promote better oil protection would be better than the cylinder wall because of blow by on the rings.

I have done the dimples on the piston skirts, its allot of work but cant say I really seen much if any wear or performance differance, but I know a few guys swear they have had good luck with them.

[croat1]

Searching YouTube I found this piston being used in a Lynx cylinder.  Anyone having this done?

[Tbone07]

Searching YouTube I found this piston being used in a Lynx cylinder.  Anyone having this done?

Wonder if that's for weight reduction on the big bore piston, or for oil retention? Cool idea though.

Got a link for the YouTube video?

[All250R]

Just speculating, but I think the edges of the pocket are more likely to act as oil scrapers than oil retention pockets, assuming the problem being solved is oil retention.
I think you may also be experimenting with the thermal expansion properties, strength and stress properties of the piston/material.
If an engine's problem is oil retention from high levels of heat, choosing an oil with a higher flash point is a more straight forward solution.
2cents.

[bholzgen]

Searching YouTube I found this piston being used in a Lynx cylinder.  Anyone having this done?

Ah yes the welded piston

[croat1]

Searching YouTube I found this piston being used in a Lynx cylinder.  Anyone having this done?

Ah yes the welded piston

Here’s the link to the video where this piston was seen. 

https://m.youtube.com/watch?v=ev2tPfzIncE

[jcs003]

Appears to be a bad idea in my opinion.   As mentioned could scrape oil away and throw the assembly out of balance if it not done with an attention to mass and location and the consideration to piston durability.   All those dimples are areas where three will be heat concentrations.  Just an assumption but I would avoid such a crazy approach that could probably be resolved with more clearance.

[Jerry Hall]

 

Searching YouTube I found this piston being used in a Lynx cylinder.  Anyone having this done?

Ah yes the welded piston

Here’s the link to the video where this piston was seen. 

https://m.youtube.com/watch?v=ev2tPfzIncE

I watched the above video and a few other of his videos:(  It is sad to see a guy that has a lot of followers/viewers, at this level of experience making videos about motor building.  I hope his viewers are watching his videos for comedy and the bling factor and not to learn new mechanical skills that they can use on their own engines and quads.