- Joined
- Nov 26, 2009
- Messages
- 3,184
Drilled, lightened and oil grooved piston skirt lubrication experiments below.
When I started thinking about doing this some people said that I shouldn't or couldn't - so of course I went ahead and did it.
The drilled Hepolites below went well for 60,000 miles until the ring lands loosened and it began to rattle and smoke like a pig. There was .001" bore wear near the top.
Another bore life increasing experiment with Hepolite pistons. Oil from the oil collector groove & oil scraper rings is allowed to channel down the very shallow X grooves (.005" deep) and coat the skirt with oil on the upstroke. I've considered making this modification available but I have to hand craft the grooves by hand (with a guide) and its difficult. I would probably leave out the short vertical groove.
Earlier photo of my latest lightweight drilled pistons - more lube to the bore wall through the drilled skirts. These pistons now have 20,000 miles on them and show 0 leakage on a leak down tester with gapless rings. No measurable bore wear so far. Lightened to 170 grams bare.
When I started thinking about doing this some people said that I shouldn't or couldn't - so of course I went ahead and did it.
The drilled Hepolites below went well for 60,000 miles until the ring lands loosened and it began to rattle and smoke like a pig. There was .001" bore wear near the top.
Another bore life increasing experiment with Hepolite pistons. Oil from the oil collector groove & oil scraper rings is allowed to channel down the very shallow X grooves (.005" deep) and coat the skirt with oil on the upstroke. I've considered making this modification available but I have to hand craft the grooves by hand (with a guide) and its difficult. I would probably leave out the short vertical groove.
Earlier photo of my latest lightweight drilled pistons - more lube to the bore wall through the drilled skirts. These pistons now have 20,000 miles on them and show 0 leakage on a leak down tester with gapless rings. No measurable bore wear so far. Lightened to 170 grams bare.