Call me skeptical on convincing CARB to allow anything but what they want - I remember hearing the story about CARB forcing Honda to add catalytic converters to the original CVCCs even though the cars were meeting the emissions specs without them. Some day I gotta figure out if that was true or just urban legend, but frankly given the way CARB operates it's entirely believable.
What are the downsides to "gapless" setups, why don't OEMs use them if they have such great benefits?
The 20% mileage improvement was for the whole package -- dimples, ceramic coating, and gapless rings, not just the rings.
The initial diesel engine test of the pistons was on gigantic mining dump trucks with CAT engines. The mine was having problems with some of their newer engines where the rings would get fouled with carbon and break (if I remember right). They rebuilt two of the CAT engines identically except for the pistons and ran a test for some number of operating hours. The Speed of Air pistons solved the ring carbon fouling. The company also does oil analysis to determine oil change intervals, and the SoA engine required fewer than half the changes of the other engine and might have gone longer, except that they hit a CAT max hours limit well before the analysis indicated a change needed. The SoA engine also got considerably better fuel economy, but I don't think they documented it at the time because that wasn't the problem they were trying to solve. Since the trucks are worth a large number of dollars per hour to the mine, at the end of the test, the mine said the savings in downtime on the extra oil changes alone paid for the SoA pistons.
Ok, so more than a couple dollars. But the question still remains - if it worked, why wouldn't manufacturers use it? One set of whiz-bang pistons costs maybe $3 grand, but a million sets will cost much closer to the current plain-jane pistons. They'd save a fortune on warranty repairs, if the hype is true.
A huge operation should be documenting fuel usage of their big machines, along with hours and fluids and filters. If fuel consumption deviates below norm, that indicates a problem that needs addressing.
A lot of "details" by the CEO, and zero data of apples to apples comparisons. Meanwhile Dave and his boys just eat up the sales pitch as if it's their first time seeing sliced bread.
actually, we finally got some dyno figures. fisher motor works got their hands on some meant for the BMW M57.
look for the comment "Have you guys or SOA talked to totalseal about piston rings for M57?"
i do wonder what type of math is involved in dimpling the pistons..... my work has a formula-SAE racing team with a fab shop, and i have an "in" there. they would love to do something like this
Trial and error is probably just as good as paying a DARPA Nuculer Professor Who Wrote The Book On Fluid Dynamics to run simulations. I would go with the general size/layout seen in their video, perhaps evenly-spaced instead of their slightly irregular pattern. I dont think fine-tuning the dimples would buy you much gain.
page 7, Percent Fuel Savings SOA vs Stock -- less than 8%
saw that too, though it does appear the piston is better than stock....... but still unclear if those benefits are from coating it or from dimples.
Or the rings. Their pistons have all 3 mods, and maxed out at 8% efficiency gains. It's fair to say none of us drive enough to ever recover the cost of their pistons, let alone the labor. If dimples alone were the main factor, and you were already rebuilding your engine, it would be worth some time on the drill press.
or, having seen how companies like Bosch operate, i wouldnt be surprised if they did see an improvement but now are trying to "clean room" their own dimpled piston designs as to not pay licensing / royalities to SOA.
It would more likely be Mahle or Kolbenschmidt than Bosch. Bosch doesn't make engine pistons, afaik.
im aware, just pointing out how a conglomerate like bosch can be petty. so no doubt the others are like this too
but big car good! cmon, consume man, buy buy buy! you NEED that new, shiny, neat, cool, fancy facelifted car! /s
Then they run those 10 speeds at over 200* and they fail. Hard parts. CDF drum walks apart. Oh and when you hit the gas to pass someone on the highway, they also neutral out then drop into 1st gear. Lotsa fun.
