Cool piston tech

Rob Mayercik

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If they can prove to the EPA and CARB that - say, a 2015 Duramax - can meet the 2015 emission standards with a rebuild using their piston kit without the after treatments, I think they can be legally certified to run that way. That is what Speed of Air is working on, and I guess we'll see what happens. I'll be here cheering them on and rooting for their success.
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.

In any event, if they do pull it off my hat's off to them...
 

oilhammer

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There are just too many to list....
CARB forced a bunch of crap on California-only Volkswagens in the '70s and '80s. And they could do it, because at that time, Volkswagen sold a significant chunk of the US sales in that state... more than any other. Some examples: 1974 Beetles, Ghias, and Things got a dual-preheated intake manifold, which meant the entire intake manifold, muffler, rear tin, was all specific to JUST those cars. 1974 Transporters with automatic transmissions got L-jet EFI. Manuals, and the rest of the country regardless of transmission got dual carbs for '74 (1975 all the Transporters got Bosch L-jet, as did the Beetles). My 1979 CA spec Transporter had electronic ignition (no points, like everyone else had), no EGR (curious... as the others DID), a completely different CA-only exhaust system with a specific catalyst that cooked the left cylinder head to death, and lambda feedback control (49 state Transporters did not have lambda control, and had a tiny little catalyst attached right ahead of the muffler).

Bunches of other CA-only stuff from that era... like the often made-fun-of 1980 CA-only Corvette, that was automatic-only, and 5.0L smogified V8 that managed a whole 105hp ... LMAO!

Don't see that anymore, because other states were allowed to adopt these CARB standards, and it became more difficult to make two versions. But there are still certain cars that were sold primarily [new] in CARB states that were not sold elsewhere. Like the Altima hybrid, or the RAV4-EV, etc.
 

adjat84th

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They also add a gapless ring (wonder why the oil is cleaner?) and heat barrier coating to the top. Over on BITOG someone compared a set of Speed of Cash Leaving Your Wallet pistons to Mahle pistons, coated, plus gapless rings. The dimples made the fancy pistons cost 3X as much ($1200 vs $3700). I don’t remember what engine they were for, though.
What are the downsides to "gapless" setups, why don't OEMs use them if they have such great benefits?
Fisher Motor Works did a BMW with the fancy pistons, and (likely most importantly) gapless ring setup and saw 200C decrease in EGT across the rev range, substantial increase in torque (though they also saw an increase in compressor surge), and a claimed 20% increase in fuel economy.
I'd rather see the datalogs from their testing vs dyno charts, but they were very interesting results either way.
 

oilhammer

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There are just too many to list....
I've often wondered the same thing about the gapless rings... because I do not know of any OEM that uses them in their engines (but there may be some exotic exception?).
 

turbodieseldyke

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If they could get an instant 20% mpg improvement & the rings only add a few dollars to the build price, why wouldn't they all use it? I could understand if it was still 1970 and the Big 3 were colluding with Big Oil to waste everyone's money, but with all the foreign competition onshore... probably not.
 

turbobrick240

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Too bad they aren't still doing the Mythbusters show. That would be a good one. Two brand new engines run side by side in dyno cells with full instrumentation.
 

oilhammer

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There are just too many to list....
Engine Masters, on MT Television... I think Freiburger and company would do it justice.

Of course, the problem with that is they have paid advertisers...
 

shoebear

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If they could get an instant 20% mpg improvement & the rings only add a few dollars to the build price, why wouldn't they all use it? I could understand if it was still 1970 and the Big 3 were colluding with Big Oil to waste everyone's money, but with all the foreign competition onshore... probably not.
The 20% mileage improvement was for the whole package -- dimples, ceramic coating, and gapless rings, not just the rings.
 

shoebear

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Too bad they aren't still doing the Mythbusters show. That would be a good one. Two brand new engines run side by side in dyno cells with full instrumentation.
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.

You should watch the video I posted. It goes into lots of details.
 
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turbodieseldyke

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The 20% mileage improvement was for the whole package -- dimples, ceramic coating, and gapless rings, not just the rings.
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.

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.
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.
 

adjat84th

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You should watch the video I posted. It goes into lots of details.
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.
When we see a coated stock piston running gapless rings, compared to a SOA dimpled version..then we'll get a true comparison.
 

lemoncurd

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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.
When we see a coated stock piston running gapless rings, compared to a SOA dimpled version..then we'll get a true comparison.
actually, we finally got some dyno figures. fisher motor works got their hands on some meant for the BMW M57.

no, they arent using total seal / gapless rings. but it is still unclear if the gains seen are due to the dimpling or the piston coating. regardless, results are results.


here, they say they are testing in a VW TDI soon (TM). they said about 14-16 weeks ago they would test it in "a month"
they posted this more recently mentioning the VW TDI aswell

they said in some other comments, if they see good results on the VW TDI theyre going to put them into the CJAA. the VW TDI theyre testing first is a mk7 golf
 

lemoncurd

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Where do you see mention of type of rings used?
look for the comment "Have you guys or SOA talked to totalseal about piston rings for M57?"

they replied to that saying: yes and the second engine we are assembling has total seal rings. That should give us some idea of what difference if any a gapless second ring makes

so the first engine they tested with it didnt use gapless rings
 

adjat84th

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Would be nice if they mention that in their original post/findings.
Even so, the real comparison will be a coated stock piston vs the SOA. The piston coatings have been out for a long time and are a fraction of the cost of the SOA dimpled pistons.
 

lemoncurd

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Would be nice if they mention that in their original post/findings.
Even so, the real comparison will be a coated stock piston vs the SOA. The piston coatings have been out for a long time and are a fraction of the cost of the SOA dimpled pistons.
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

if i could dimple the pistons myself, then go get them coated it would probably be a fraction of the price of SOA.
 

turbodieseldyke

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i do wonder what type of math is involved in dimpling the pistons
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.
 

adjat84th

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The second FB link that @lemoncurd shared a few posts up does show the EA288 (MK7 engine) pistons, and the dimples look totally uniform/evenly placed rather than random. Will be interesting to see their results, even if it's still not apples to apples.
 

turbodieseldyke

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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.
 

oilhammer

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There are just too many to list....
To a manufacturer, 8% would be huge. They install crap like start/stop and use engine-punishing water-thin oils and crappy tires for less gains.

That's why it seems sketchy if it is that good why no manufacturer is jumping on it. The scale of production would drop the cost down to probably only a few dollars over standard pistons. Ford has penny-pinched over the coatings on radio buttons for less.
 

turbobrick240

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I wouldn't be surprised if some of the big diesel engine manufacturers like Volvo, Cummins, CAT, Deere and others have bought the dimpled pistons and run their own tests. And likely determined that there is no magic fairy dust.
 

lemoncurd

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I wouldn't be surprised if some of the big diesel engine manufacturers like Volvo, Cummins, CAT, Deere and others have bought the dimpled pistons and run their own tests. And likely determined that there is no magic fairy dust.
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.

even companies like Bosch are this petty.
 

turbobrick240

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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.

even companies like Bosch are this petty.
It would more likely be Mahle or Kolbenschmidt than Bosch. Bosch doesn't make engine pistons, afaik.
 

turbodieseldyke

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It's been mentioned in one of these threads that Volvo already has pistons with wave patterns on the surface.

I can understand why manufacturers wouldn't spend $10 to improve efficiency by 8%. They see their customers buying gas guzzling SUVs instead of regular cars, so why bother to help someone who doesn't care about pissing money away.
 

oilhammer

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There are just too many to list....
...because the gov't told them to. I agree, it may seem silly to pursue ways to make a 13 MPG pig get 14 MPGs while 30 MPG cars sit and gather dust and 50 MPG cars are deemed illegal, but that's exactly what they do. They are not putting these 10sp slushboxes in giant trucks and SUVs for fun. Consumers can be very strange. And dumb.
 

lemoncurd

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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


...because the gov't told them to. I agree, it may seem silly to pursue ways to make a 13 MPG pig get 14 MPGs while 30 MPG cars sit and gather dust and 50 MPG cars are deemed illegal, but that's exactly what they do. They are not putting these 10sp slushboxes in giant trucks and SUVs for fun. Consumers can be very strange. And dumb.
but big car good! cmon, consume man, buy buy buy! you NEED that new, shiny, neat, cool, fancy facelifted car! /s
 

Zak99b5

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...because the gov't told them to. I agree, it may seem silly to pursue ways to make a 13 MPG pig get 14 MPGs while 30 MPG cars sit and gather dust and 50 MPG cars are deemed illegal, but that's exactly what they do. They are not putting these 10sp slushboxes in giant trucks and SUVs for fun. Consumers can be very strange. And dumb.
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.
 
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