LiquidPiston motor , anybody seen these ??

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Rep732 said:
Ugly ass thing that is. I hate the half door for passengers.
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Yep it's a space ship. Very comfortable to sit in and handles 30x better then a rx7. Shite engine with out some work, and it's an auto so it's down something like 90hp over the stick shift. Pos shifts at 6k. Cant even hold a gear out in tiptronic mode with out a programmer. It was here first car, and no one would cosign for it. So whatever. I have a list of stuff for it if she ever sells it to me. Wont give her more then $1500.00 tbh. First thing it needs is 6 gears and a 3rd pedal.
 
Seandonato73 said:
A wankle make 3 combustion cycles for every revolution. Feks sake do you look anything up before you spout off about it? It's a reinvented engine. Nothing new or special, they took someone else's design. Modified it. And over complicated the intake and exhaust process. I'll believe how great it in when ford and chevy start using them.
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go Fek urself super queen Jezz what an azz
 
buzzkill said:
https://snowgoer.com/news/first-impressions-ski-doo-summit-850-e-tec-turbo/28334/

Nope you cant turbo a 2 stroke , OOOPPPSSSS , I do recall this from somewhere ?????


have a nice day kids
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Alright let me break this down I to fricken idiot terms since that's what its needed. Forced Induction is a waste of fuckeing time on a 2 stroke, it only works at wide open throttle and barely make a fricken difference. Everyone that has tried has failed miserably, believe me if it could be done and work worth a poop, with out valves or would be in production. Not some back woods dip shite, that bolts a turbo on a two stroke, rejets the carb and says it doubled its hp. Sorry doesn't work like that. Go back to school and learn how a fiddlesticking 2 stroke works.
And your post about the ski do is a custom tailored engine that more 4 stroke tech then 2 stroke. It doesn not use the piston for induction. It has valves in it for doing the exhaust work.
 
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show me a exhaust valve , sorry but I pretty sure the Ski-Doo / Rotax would not do this IF it cant happen ! watch the video there is NO EXHAUST VALVE , they must be smarter than us , go figure .

Im gonna believe ROtax over the SHOP boys LMFAO
 
Ok first your wrong, they have exhaust valves, or sliders to control the exhaust port size, along with the reeds, intake bypass valves, amd a waste gate. They also use direct injection, and boost injectors in the throttle body. Hell even the crank bearings are oiled like a 4 stroke. So yes I guess I was wrong that you turbo a 2 stroke, but I guess at the same time I was right as well. This engine was specifically made for the turbo. It's about as far away from a loop scavenged 2 stroke as you can possibly get. They solved the nagging low end torque and fuel consumption issues with the direct injection and (you guessed it) exhaust valves. (Funny did I mention that you needed valves ? Oh yeah I did) and to help that out they needed the waste gate to do 2 things, manage exhaust pressure to keep the air in the cylinder and to keep the turbo at its happy place at a maximum 4 psi (good lord were just making tons of power at that level of boost) the only benefit of this over complicated mouse trap is it retains power at altitude. Will it last ?‍♂️ you got me, being a brand new engine and largely untested tech to make it a turbo engine idk. Time will tell that. But since were on the sled notion I will say there have been turbo kits for them and other 2 strokes for years, they all have a few things in common. High octane fuel is needed, fuel economy goes to the dogs, and they are unreliable at best. Found an over abundance of information about guys installing these "turbo kits" and sled engine meeting a short death, for various reasons. So in short no you cant turbo a 2 stroke. Well you can if your pockets are deep enough and you make it surprisingly like a 4 stroke, just with extra parts and twice the electronics to keep it in its happy place. Have fun with that in an rc car or whatever dinosaur of a 2 stroke you want to experiment with.
Cheers.
 
I 100% agree with seand , the issue all along has been the fact that 2 strokes operate most efficiently on the fundamental concept of "pulse flow". A "pulse" is BOTH a momentary pressure, then a momentary vacuum. With a turbo (or NOS) they function all with "forced" flow only. Many attempts have been made over many years trying to turbo or NOS inject a 2 stroke and they simply didn't work well enough to see the advantage in the past. Now maybe BRP has found the high tech engineering to force induct a 2 stroke, IDK .
 
Polar_Bus said:
I 100% agree with seand , the issue all along has been the fact that 2 strokes operate most efficiently on the fundamental concept of "pulse flow". A "pulse" is BOTH a momentary pressure, then a momentary vacuum. With a turbo (or NOS) they function all with "forced" flow only. Many attempts have been made over many years trying to turbo or NOS inject a 2 stroke and they simply didn't work well enough to see the advantage in the past. Now maybe BRP has found the high tech engineering to force induct a 2 stroke, IDK .
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I always wondered if it was possible to air inject a 2 stroke when it was in mid compression. Would make a banger of a time I'm sure.
 
Troopermaniac said:
I always wondered if it was possible to air inject a 2 stroke when it was in mid compression. Would make a banger of a time I'm sure.
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Forced induction of a 2 stroke has and can be done. You just need valves. Which adds weight and complexity. Hence why we had the 2 stroke detroit. It has exhaust valves and needs the blower to run. The power wasnt that great and they had a whole host of issues of their own. Great engines in their day, but a kinda modern 4 stroke can out pace them in power amd fuel economy easily.
 
Seandonato73 said:
Ok first your wrong, they have exhaust valves, or sliders to control the exhaust port size, along with the reeds, intake bypass valves, amd a waste gate. They also use direct injection, and boost injectors in the throttle body. Hell even the crank bearings are oiled like a 4 stroke. So yes I guess I was wrong that you turbo a 2 stroke, but I guess at the same time I was right as well. This engine was specifically made for the turbo. It's about as far away from a loop scavenged 2 stroke as you can possibly get. They solved the nagging low end torque and fuel consumption issues with the direct injection and (you guessed it) exhaust valves. (Funny did I mention that you needed valves ? Oh yeah I did) and to help that out they needed the waste gate to do 2 things, manage exhaust pressure to keep the air in the cylinder and to keep the turbo at its happy place at a maximum 4 psi (good lord were just making tons of power at that level of boost) the only benefit of this over complicated mouse trap is it retains power at altitude. Will it last ?‍♂️ you got me, being a brand new engine and largely untested tech to make it a turbo engine idk. Time will tell that. But since were on the sled notion I will say there have been turbo kits for them and other 2 strokes for years, they all have a few things in common. High octane fuel is needed, fuel economy goes to the dogs, and they are unreliable at best. Found an over abundance of information about guys installing these "turbo kits" and sled engine meeting a short death, for various reasons. So in short no you cant turbo a 2 stroke. Well you can if your pockets are deep enough and you make it surprisingly like a 4 stroke, just with extra parts and twice the electronics to keep it in its happy place. Have fun with that in an rc car or whatever dinosaur of a 2 stroke you want to experiment with.
Cheers.
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Where did you get all this info ? I could not find that much detail ! Rotax makes the motor they are very well known for excellent 2 stroke engines so I figure it will work over time ( to much to loose if it is crap ) I figured they were using the waste gate to control back pressure somehow/
 
Theres a video on the tech behind the e tech engine from rotax. Shows the valving in the engine, the target line system, and fuel system. The video you liked showed the waste gate and intake bypass valve. Just had to do some research and find the info. They arw trying to be very hush hush about this engine, but there are only so many ways they can pull it off, without going full on forced induction, which adds considerable weight, and had a host of issues all it's own. The variable exhaust valve has been in play for a few years, now it controlled by the computer not a cable. The direct injection has also been out for a few years now. The booster injectors in the throttle bodies I did not know about. The info is all out there just need to be determined to find it. I'm all about a healthy discussion when all the facts are brought to the table. This engine has been in development for years. As seen by the evolution of the e tech and its immediate predecessor. It all falls in line if you looks at it chronologically. Direct injection and variable exhaust valving. Needed to mitigate fuel leaving the combustion chamber, and allow enough flow at top rpm for the turbo to spool quickly. Extra injectors to compensate for low and mid range issues before the turbo spools, and I think to help with the direct injectors keep up without too much of a duty cycle (speculation on my part) the targeted lube system was necessary for a few reasons. The crank had to be kept light, and so the bearing size suffered, targeted lube like a 4 stroke puts oil where its needed. At the bearings. EPA emissions I'm sure were the other reasons. But the side effects of that is an engine that runs on very little oil, which is a win for the consumer. Once you know all this it falls into place. It's no longer really a 2 stroke, it's a force of will to stay one step ahead of the competition, time will tell if it's a good engine or not, rotax has a good track record but this is a first, and there has been some evidence of issues. Weather it was self induced or not has yet to be seen.
 
Seandonato73 said:
Theres a video on the tech behind the e tech engine from rotax. Shows the valving in the engine, the target line system, and fuel system. The video you liked showed the waste gate and intake bypass valve. Just had to do some research and find the info. They arw trying to be very hush hush about this engine, but there are only so many ways they can pull it off, without going full on forced induction, which adds considerable weight, and had a host of issues all it's own. The variable exhaust valve has been in play for a few years, now it controlled by the computer not a cable. The direct injection has also been out for a few years now. The booster injectors in the throttle bodies I did not know about. The info is all out there just need to be determined to find it. I'm all about a healthy discussion when all the facts are brought to the table. This engine has been in development for years. As seen by the evolution of the e tech and its immediate predecessor. It all falls in line if you looks at it chronologically. Direct injection and variable exhaust valving. Needed to mitigate fuel leaving the combustion chamber, and allow enough flow at top rpm for the turbo to spool quickly. Extra injectors to compensate for low and mid range issues before the turbo spools, and I think to help with the direct injectors keep up without too much of a duty cycle (speculation on my part) the targeted lube system was necessary for a few reasons. The crank had to be kept light, and so the bearing size suffered, targeted lube like a 4 stroke puts oil where its needed. At the bearings. EPA emissions I'm sure were the other reasons. But the side effects of that is an engine that runs on very little oil, which is a win for the consumer. Once you know all this it falls into place. It's no longer really a 2 stroke, it's a force of will to stay one step ahead of the competition, time will tell if it's a good engine or not, rotax has a good track record but this is a first, and there has been some evidence of issues. Weather it was self induced or not has yet to be seen.
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Nothing wrong with a robust discussion , it is still technically a 2 stroke just highly modified from a piston port LOL ! time will tell if this actually is a step forward or sideways ?? Power exhaust valves have been around a long time my Yamaha RZ350 had them , they were computer controlled or just throttle position feedback loop ?
 
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