any one seen this before??
03-04-2008, 08:52 AM
#28
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RE: any one seen this before??
ORIGINAL: downunder
it'll certainly work but not all that efficiently because it seems to be around a 60 degree V
it'll certainly work but not all that efficiently because it seems to be around a 60 degree V
How do you get 60 degrees?
I see less than 45 degrees....it is about 30-35 degrees.
And if you know anything about degrees in engine, the closer to 45 degrees gets you more HP while the straight's get you more Torq.
That is why VW's VR6 is a 15 degree engine. The HP and torq are about equal because it is a narrow V6.
I think the engine pictured above will work quite well.
The only con on it is the extra weight from the cast of a second cyl and cooling head.
I am very interested in seeing this engine in action!
03-04-2008, 09:01 AM
#29
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RE: any one seen this before??
People this engine cannot work...if you understand anything about how a 2 stroke works you would know this motor cannot run..... Geez this particular motor is just a show dummy, it doesn't even have 2 sleeves in the block.....
03-04-2008, 09:17 AM
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RE: any one seen this before??
This is the next step for our nitro engines. This is the only way that nitro engins will keep up with motors. Electrics already spank many single cylinder engines (except for a few engins that are definitely high dollar).
Once electrics totally spank engines, you will begine to see these multi cylinder engines come to the US and cars & tucks redeigned with much higher gear ratios and reinforced to in turn take the higher torque outputs.
Once electrics totally spank engines, you will begine to see these multi cylinder engines come to the US and cars & tucks redeigned with much higher gear ratios and reinforced to in turn take the higher torque outputs.
03-04-2008, 09:24 AM
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RE: any one seen this before??
ORIGINAL: HitTheDirt!
How do you get 60 degrees?
I see less than 45 degrees....it is about 30-35 degrees.
And if you know anything about degrees in engine, the closer to 45 degrees gets you more HP while the straight's get you more Torq.
That is why VW's VR6 is a 15 degree engine. The HP and torq are about equal because it is a narrow V6.
I think the engine pictured above will work quite well.
The only con on it is the extra weight from the cast of a second cyl and cooling head.
I am very interested in seeing this engine in action!
ORIGINAL: downunder
it'll certainly work but not all that efficiently because it seems to be around a 60 degree V
it'll certainly work but not all that efficiently because it seems to be around a 60 degree V
How do you get 60 degrees?
I see less than 45 degrees....it is about 30-35 degrees.
And if you know anything about degrees in engine, the closer to 45 degrees gets you more HP while the straight's get you more Torq.
That is why VW's VR6 is a 15 degree engine. The HP and torq are about equal because it is a narrow V6.
I think the engine pictured above will work quite well.
The only con on it is the extra weight from the cast of a second cyl and cooling head.
I am very interested in seeing this engine in action!
In reality, I would use a 180degree angle for this engine. with 3 cylinders, a radial with 120 degrees, for 6 cylinders, radial with 60degree intervals. I would not go V or in-line unless I had 6 cylinders so as to llow the cylinders to fire no less than 60degress from each other.
03-04-2008, 09:34 AM
#32
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RE: any one seen this before??
ORIGINAL: HitTheDirt!
And if you know anything about degrees in engine, the closer to 45 degrees gets you more HP while the straight's get you more Torq.
And if you know anything about degrees in engine, the closer to 45 degrees gets you more HP while the straight's get you more Torq.
So, assuming the same cylinder pressure at the instant of ignition, a single cylinder engine with its crank at 90degrees past TDC is making max torque.
In reality, the cylinder pressure has reduced by this point since the combustion has already occured and the cylinder volume has already increased. by the work-vloume theorem, the instantaneous force is just a little less at 90degrees after TDC than at the instant just after combustion. But the crank, piston, conrod geometry still determins the instantaneous torque.
03-09-2008, 11:22 AM
#33
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RE: any one seen this before??
As said the intake timing is going to not be optimal for both cylinders as it's on the crank. Unless The crank has 2 intake ports on it but being as this is a V design and not a 180* opposing engine it would be tough to have 2 intake ports on the crank for both cylinders. And you can't make the cylinder fie whenever you want as the compression and glow plug do the igniting unlike a banshee that uses spark plugs and an ignition system to make it fire.
I'm not to sure if it wouldn't work but I don't think the gains are going to be worth the drawbacks. It might produce more power than a single but probably not enough to warrant the extra fuel consumption and weight.
I understand what supertib is talking about the shared crankcase. In this small scale engine it might not be as much of a drawback as it is in larger engines. Will it effect performance? Of course it will.
Everything else aside. It does look cool. Would be great for a shelf queen. And I would think the exhaust note would be wicked.
I'm not to sure if it wouldn't work but I don't think the gains are going to be worth the drawbacks. It might produce more power than a single but probably not enough to warrant the extra fuel consumption and weight.
I understand what supertib is talking about the shared crankcase. In this small scale engine it might not be as much of a drawback as it is in larger engines. Will it effect performance? Of course it will.
Everything else aside. It does look cool. Would be great for a shelf queen. And I would think the exhaust note would be wicked.
03-09-2008, 12:13 PM
#34
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RE: any one seen this before??
ORIGINAL: SAVAGEJIM
This is the next step for our nitro engines. This is the only way that nitro engins will keep up with motors. Electrics already spank many single cylinder engines (except for a few engins that are definitely high dollar).
Once electrics totally spank engines, you will begine to see these multi cylinder engines come to the US and cars & tucks redeigned with much higher gear ratios and reinforced to in turn take the higher torque outputs.
This is the next step for our nitro engines. This is the only way that nitro engins will keep up with motors. Electrics already spank many single cylinder engines (except for a few engins that are definitely high dollar).
Once electrics totally spank engines, you will begine to see these multi cylinder engines come to the US and cars & tucks redeigned with much higher gear ratios and reinforced to in turn take the higher torque outputs.
Jim you should know that this motor cannot run..... this is a a 100% fictional model used for show purposes only ..it is impossible for this motor to work.....
03-09-2008, 07:56 PM
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RE: any one seen this before??
Firstly....I can't believe we're still looking at this....and secondly I totally agree with supertib.
If a multi-cylinder two stroke is sharing the same crankcase then the pistons will have to operate in unison to ensure adequate fuel supply to each cylinder.....picture the crank window opening and letting fuel in ,the first piston to pass bdc will consume all. Not only this but even if the pistons ARE operating in unison then (as already said) the twin will be un-balanced....which is why the airplane engines are multi-cylinder rotary configuration with all cylinders firing at the same time.
If 'they' wish to develop a two stroke twin for rc use, it'll need separate crankcases for each cylinder.....let alone I wouldn't imagine that carb. would be able to supply enough fuel for two cylinders.
As Sman said....too many armchair engineers here.....maybe some peeps should research 'Operating principles of two stroke engines'....
If a multi-cylinder two stroke is sharing the same crankcase then the pistons will have to operate in unison to ensure adequate fuel supply to each cylinder.....picture the crank window opening and letting fuel in ,the first piston to pass bdc will consume all. Not only this but even if the pistons ARE operating in unison then (as already said) the twin will be un-balanced....which is why the airplane engines are multi-cylinder rotary configuration with all cylinders firing at the same time.
If 'they' wish to develop a two stroke twin for rc use, it'll need separate crankcases for each cylinder.....let alone I wouldn't imagine that carb. would be able to supply enough fuel for two cylinders.
As Sman said....too many armchair engineers here.....maybe some peeps should research 'Operating principles of two stroke engines'....
03-10-2008, 03:12 PM
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RE: any one seen this before??
I've not seen a 2 stroke radial but the 4 stroke radials do not have all cylinders firing at the same time. I'd like to see a v-engine with all pistons at tdc at the same time. I don't think that's possible.
03-10-2008, 08:05 PM
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RE: any one seen this before??
ORIGINAL: supertib
this motor wont run and you don't need to be an engineer to see that..... having 2 differently timed pistons sharing a common crankcase would end up making a dam bomb.......... I have been running Snowmobiles for years and have blown many crank seals on my engines..multi cylinder 2 strokes don't
like sharing the crankcase.. they go bang very fast when a crank seal lets go.......
the only way this sirio could operate on the same crankcase volume is if both pistons hit TDC and BDC at the same time... they have rotary 5 cylinder 2 strokes for aircraft, but each piston has its own crankshaft working off a common central crank, and all 5 pistons fire at the exact same time... so even though it has 5 cylinders it fires as just a big single..........
the only way to make multi cylinder 2 strokes work is if you can isolate each cylinders crankcase, or if you fire each piston at the exact same time. there is no other way around this..........
This Sirio is just a model to attract attention, the model at the show only has 1 piston in it and the other side is wide open.... why on Earth would Sirio spend millions developing a motor that wont fit into any commercially available RC's...look how wide the block is and tell me where that would fit.... So really can you see Sirio developing a motor for a non existent market....or is this a nice little model for the toy show made to attract attention....
StManB why dont you load this into MODA and see if a multi cylinder 2 stroke can run like this..both piston sharing the same crankpin and crankcase volume...
this motor wont run and you don't need to be an engineer to see that..... having 2 differently timed pistons sharing a common crankcase would end up making a dam bomb.......... I have been running Snowmobiles for years and have blown many crank seals on my engines..multi cylinder 2 strokes don't
like sharing the crankcase.. they go bang very fast when a crank seal lets go.......
the only way this sirio could operate on the same crankcase volume is if both pistons hit TDC and BDC at the same time... they have rotary 5 cylinder 2 strokes for aircraft, but each piston has its own crankshaft working off a common central crank, and all 5 pistons fire at the exact same time... so even though it has 5 cylinders it fires as just a big single..........
the only way to make multi cylinder 2 strokes work is if you can isolate each cylinders crankcase, or if you fire each piston at the exact same time. there is no other way around this..........
This Sirio is just a model to attract attention, the model at the show only has 1 piston in it and the other side is wide open.... why on Earth would Sirio spend millions developing a motor that wont fit into any commercially available RC's...look how wide the block is and tell me where that would fit.... So really can you see Sirio developing a motor for a non existent market....or is this a nice little model for the toy show made to attract attention....
StManB why dont you load this into MODA and see if a multi cylinder 2 stroke can run like this..both piston sharing the same crankpin and crankcase volume...
just wondering did youever take a look at a Honda RS 250, from what I know they have 1 crank but are at a 90degree v. And they make much more power then a cr 250 does, both cylinders are 125 and the one is upright and the other is in a layed down almost horizontal position I believe. It's been a while since I've seen one or checked up on them. But I believe that they use a single carb also.
Not saying that you arent correct in that it wont work. Just asking though as your usually very knowledgable about these things. Now as far as there is no market it has all grabbed our attention, and where there's a will there's a way. I have seen T-Maxx's with 2 and 3 engine's on them so there is a way for them to work. you just ahve to move some thigns around.
03-11-2008, 12:03 AM
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RE: any one seen this before??
That and some type of conversion to fit something this gynormious into a 1/8 anything. Why would a company throw out a concept engine and show the insides of it? would be just like saying " here take our idea before we decided to develop it "
Sorry but im still a believer of "nothing is impossible"
You wanna take about something "impossible"? does anyone have a cell phone? ( how the hell could we make something like that )
SO my point being is yes, if there's a will, there is way. But i like jim's idea also, It would be nice to see some progression in the would of nitro RC's
Sorry but im still a believer of "nothing is impossible"
You wanna take about something "impossible"? does anyone have a cell phone? ( how the hell could we make something like that )
SO my point being is yes, if there's a will, there is way. But i like jim's idea also, It would be nice to see some progression in the would of nitro RC's
03-11-2008, 12:58 AM
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RE: any one seen this before??
here is a pic of a honda RS 250 engine, as you can see the cylinder are very offset, plenty of room to run seperate crankcase volumes for each cylinder, even if they're feed from a single carb, tib is hardly ever wrong when it comes to engines.
03-11-2008, 02:14 AM
#43
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RE: any one seen this before??
ORIGINAL: iexion
That and some type of conversion to fit something this gynormious into a 1/8 anything. Why would a company throw out a concept engine and show the insides of it? would be just like saying " here take our idea before we decided to develop it "
Sorry but im still a believer of "nothing is impossible"
You wanna take about something "impossible"? does anyone have a cell phone? ( how the hell could we make something like that )
SO my point being is yes, if there's a will, there is way. But i like jim's idea also, It would be nice to see some progression in the would of nitro RC's
That and some type of conversion to fit something this gynormious into a 1/8 anything. Why would a company throw out a concept engine and show the insides of it? would be just like saying " here take our idea before we decided to develop it "
Sorry but im still a believer of "nothing is impossible"
You wanna take about something "impossible"? does anyone have a cell phone? ( how the hell could we make something like that )
SO my point being is yes, if there's a will, there is way. But i like jim's idea also, It would be nice to see some progression in the would of nitro RC's
this isnt rocket science dude...that Sirio engine cannot run the way its built..... 2 cylinder 2 strokes work fine, but you must be able to run each piston in its own sealed crankcase.... If 2 pistons do share 1 crankcase then they must hit TDC and BDC at the exact same time, which means they must fire at the same time as well......... a V-Twin like in the picture cannot run the way they have modeled it..
Radial 2 strokes fire each piston at the same time.. each piston has its own separate crankshaft thats connects to a main center shaft........ so in essence the motor still fires like a single cylinder.....
03-11-2008, 02:55 AM
#44
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RE: any one seen this before??
l dunno how old this thread is, and being half pissed who gives a, but ;l can pretty much take a guarrenteed bet with any turkey here that this engine design WILL work, period, anyone for the bet, you name the price ! LOL !
pleaaaaaaaaaaaaaaaaaaaaaase ?
When designed RIGHT a twin V will outright PWN any single currently on the market, the trick is getting it RIGHT.....
Yes even with nitro compression designed engines this will work awsomely.
lm half pissed and an ex diesel mechanic and l know that, come on guys.....
pleaaaaaaaaaaaaaaaaaaaaaase ?
When designed RIGHT a twin V will outright PWN any single currently on the market, the trick is getting it RIGHT.....
Yes even with nitro compression designed engines this will work awsomely.
lm half pissed and an ex diesel mechanic and l know that, come on guys.....
03-11-2008, 03:20 AM
#45
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RE: any one seen this before??
not with a loop scavenging engine it won't, diesels aren't loop traditional loop scavenging engines, beer, you know that, unless you use ether separate crankcase volumes or forced induction like diesel two strokes do, it's not gonna work.
sober up a bit lol
sober up a bit lol
03-11-2008, 06:32 AM
#46
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RE: any one seen this before??
ORIGINAL: beer=food
l dunno how old this thread is, and being half pissed who gives a, but ;l can pretty much take a guarrenteed bet with any turkey here that this engine design WILL work, period, anyone for the bet, you name the price ! LOL !
pleaaaaaaaaaaaaaaaaaaaaaase ?
When designed RIGHT a twin V will outright PWN any single currently on the market, the trick is getting it RIGHT.....
Yes even with nitro compression designed engines this will work awsomely.
lm half pissed and an ex diesel mechanic and l know that, come on guys.....
l dunno how old this thread is, and being half pissed who gives a, but ;l can pretty much take a guarrenteed bet with any turkey here that this engine design WILL work, period, anyone for the bet, you name the price ! LOL !
pleaaaaaaaaaaaaaaaaaaaaaase ?
When designed RIGHT a twin V will outright PWN any single currently on the market, the trick is getting it RIGHT.....
Yes even with nitro compression designed engines this will work awsomely.
lm half pissed and an ex diesel mechanic and l know that, come on guys.....
If you even remotely understand how a 2 stroke works then you know this motor cannot work...obviously many of you here really do not understand how a 2 stroke works............
03-11-2008, 08:23 AM
#47
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RE: any one seen this before??
ORIGINAL: supertib
Jim you should know that this motor cannot run..... this is a a 100% fictional model used for show purposes only ..it is impossible for this motor to work.....
ORIGINAL: SAVAGEJIM
This is the next step for our nitro engines. This is the only way that nitro engins will keep up with motors. Electrics already spank many single cylinder engines (except for a few engins that are definitely high dollar).
Once electrics totally spank engines, you will begine to see these multi cylinder engines come to the US and cars & tucks redeigned with much higher gear ratios and reinforced to in turn take the higher torque outputs.
This is the next step for our nitro engines. This is the only way that nitro engins will keep up with motors. Electrics already spank many single cylinder engines (except for a few engins that are definitely high dollar).
Once electrics totally spank engines, you will begine to see these multi cylinder engines come to the US and cars & tucks redeigned with much higher gear ratios and reinforced to in turn take the higher torque outputs.
Jim you should know that this motor cannot run..... this is a a 100% fictional model used for show purposes only ..it is impossible for this motor to work.....
Also, the the induction port would need to be rethought. The crank would have to be cut such that it opens and closes twice to accomdate both cylinders. I see induction ports opposite of each other on the crank. Altentively, instead of a crank-induction, they could have devised some other method of induction opening & closing to optimize induction into the crank case. (I would have to dwell more on precisely when this induction should open and close, but I feel optomistic about it).
As for in crank case block itself, yes, this must be reinforced. Nitro engine blocks are very thin walled and the back-plate bolts leave alot to be desired for multi-cylinder sharing one crank volume application.
03-11-2008, 08:29 AM
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RE: any one seen this before??
I should add: the 180degree configuration will work best only for two cylinders. Each cylindr head opposite of each other sharing one crcnk case volume.
If more cylinders are desired, I say use only multiples of 2 cylinders, every 2 cylinders sharing one crank volume space, no more than 2 cylinders per single cracnk volume space. Each duo of cylinders must require their own induction system, the induction sytems independednt of onther duo of cylinder's induction.
If more cylinders are desired, I say use only multiples of 2 cylinders, every 2 cylinders sharing one crank volume space, no more than 2 cylinders per single cracnk volume space. Each duo of cylinders must require their own induction system, the induction sytems independednt of onther duo of cylinder's induction.
03-11-2008, 08:58 AM
#49
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RE: any one seen this before??
ORIGINAL: SAVAGEJIM
It can work if rethough better and redsigned. Unlike the RS engine mentioned with separate crankcase volumes, if they insist on a single crank case volume for a multi-cylinder loop scavanging engine, they must redesign it in a 180degree configration.
Also, the the induction port would need to be rethought. The crank would have to be cut such that it opens and closes twice to accomdate both cylinders. I see induction ports opposite of each other on the crank. Altentively, instead of a crank-induction, they could have devised some other method of induction opening & closing to optimize induction into the crank case. (I would have to dwell more on precisely when this induction should open and close, but I feel optomistic about it).
As for in crank case block itself, yes, this must be reinforced. Nitro engine blocks are very thin walled and the back-plate bolts leave alot to be desired for multi-cylinder sharing one crank volume application.
ORIGINAL: supertib
Jim you should know that this motor cannot run..... this is a a 100% fictional model used for show purposes only ..it is impossible for this motor to work.....
ORIGINAL: SAVAGEJIM
This is the next step for our nitro engines. This is the only way that nitro engins will keep up with motors. Electrics already spank many single cylinder engines (except for a few engins that are definitely high dollar).
Once electrics totally spank engines, you will begine to see these multi cylinder engines come to the US and cars & tucks redeigned with much higher gear ratios and reinforced to in turn take the higher torque outputs.
This is the next step for our nitro engines. This is the only way that nitro engins will keep up with motors. Electrics already spank many single cylinder engines (except for a few engins that are definitely high dollar).
Once electrics totally spank engines, you will begine to see these multi cylinder engines come to the US and cars & tucks redeigned with much higher gear ratios and reinforced to in turn take the higher torque outputs.
Jim you should know that this motor cannot run..... this is a a 100% fictional model used for show purposes only ..it is impossible for this motor to work.....
Also, the the induction port would need to be rethought. The crank would have to be cut such that it opens and closes twice to accomdate both cylinders. I see induction ports opposite of each other on the crank. Altentively, instead of a crank-induction, they could have devised some other method of induction opening & closing to optimize induction into the crank case. (I would have to dwell more on precisely when this induction should open and close, but I feel optomistic about it).
As for in crank case block itself, yes, this must be reinforced. Nitro engine blocks are very thin walled and the back-plate bolts leave alot to be desired for multi-cylinder sharing one crank volume application.
Jim it wont work like that..... one piston at TDC and the other piston at BDC ? opposed firing 180 degrees apart ? this method would not work whatsoever..the two pistons moving would cancel out the needed crankcase pressure needed to fill the cylinder..
