Another engine design.............

[Ozwynn]

how do they travel back up on singel cyl. briggs and stratton? rotational force brings it back up

 

[94STXRanger]

i understand that but one these engines they arent connected the same. I guess on the single pistons they may be, but on the opposing ones they were not connected to those trilobes. They straddled it and only applied forces to the lobes.

 

[Wicked_Sludge]

i see what your saying....provided its a 4 stroke and not a 2 stroke...what pulls the piston back down for the intake stroke?

 

[MAKG]

apparently not. read a little more before calling me a liar

I didn't call you a liar.

Might want to back off the accusations a bit...

 

[Wicked_Sludge]

revetecs website is sort of a mess...but after screwing around on there for a bit i think i found some useful info:

the X4V2 is their newest motor. its an X 4 cylinder with 2 valves per cylinder (hense the name), 2.4 liters of displacement. their dyno sheet shows 92HP @ 3,600rpm and 149ft-lbs @ 3,000rpm....no slouch for its displacement...

but compare that to the 2.3 SOHC we all know and love at 112HP @ 4,800rpm and 135ft-lbs @ 2,400rpm...and the revetec doesnt seem all that astonishing to me really, although they are making 132ft-lbs @ 1,300rpm. i dont have a dyno sheet for the 2.3 handy but im guessing it isnt that torquey.

 

[94STXRanger]

Exactly Wicked, so how does that piston come back down? Well Captain Ledd was right about the torque, while its not a deisel engine or anything, it would seem its got a fair bit for its size. Still a cool lookin motor though.

 

[rusty ol ranger]

The wankel was a high whinder, i dont see why this one would be any different.

Why cant they just leave well enough alone?

later,
Dustin

 

[Wicked_Sludge]

The wankel was a high whinder, i dont see why this one would be any different.

Why cant they just leave well enough alone?

later,
Dustin

the wankel is a high winder because it has no reciprocating assemply, this engine does. this engine is actually more fo a low winder because the piston achieves greatest mechanical advantage on the cam at a much lower angle than a regular piston does on its crank...this is where their low torque claims come from.

94stx, i guess all it would take to move the piston back down would be an extended "connecting rod" with a bearing on the end...so a single piston would still need 2 bearings...not sure why that didnt occure to me before

 

[martin]

I didn't have time to read the whole thing but how do they calculate the displacement. In a conventional motor the piston moves up and down one time during one revolution, hence the displacement or swept volume. In this thing the piston moves up and down three time each revolution. If the volume is calculated on the three strokes it makes then the motor size for size would be considerably smaller than a conventional one.
To put in into terms everyone understands, you could put a huge displacement motor into a ranger if it was calculated three to one.

 

[shadetree]

Exactly Wicked, so how does that piston come back down? Well Captain Ledd was right about the torque, while its not a deisel engine or anything, it would seem its got a fair bit for its size. Still a cool lookin motor though.

"The bearings are mounted on the underside of the two inter-connected pistons, which maintain the desired clearance throughout the stroke."
This from the website.

The bearings are on a plate that connects the pistons together and keep the bearings in contact with the cams at all times. The plate would still be used in the single cylinder design.shady

 

[krugford]

Something else that's odd:

Have you tried to convert their BSFC numbers to conventional units? They report 212 g/hr/kW. I get 0.63 lb/hr/HP, using 452 g/lb and 0.742 kW/HP. That's significantly worse than a good conventional gasoline engine, which consumes around 0.5 lb/hr/HP.

Something isn't right here.

The math....



Interesting looking engine BTW. Shipping to 50677? I want to take one apart.