Why The Prototypes Have To Wait On The Engine

[Johnapool]

I read somewhere many years ago that a three cylinder engine could be designed to be balanced and relatively vibration free. Thus the large number of three cylinder engines manufactured for snowmobiles, motorcycles and outboard boat motors for many years. It is NOT rocket science. I feel pretty positive about the Elio engine's first trials, as a combination of other's experiences, modern computer engineering and greatly improved metal alloys and processing should lend a large positive influence.
I know the prototypes do need the Elio engine to be genuinely Elios, but a few on the road with Suzuki engines would have helped get the idea across. The little 1.0 Geo Metro engine produced 55 hp, very close to the Elio's specs. (The car weighed 1620 lbs) A newly rebuilt long block is about $1400.

 

[outsydthebox]

Yikes! I feel like I'm being whipsawed by the variety of topics in this thread!

Back to the OT for a moment, I thought I read somewhere that the Elio engine had a 120-degree crank, giving it a smooth(er) operational cycle than the 180-degree, 2-1 crank that would be more typical of a "bandsawed" 4-cylinder.

I know a 3-cyl, 2-stroke is very smooth, getting evenly-spaced firing pulses, but does this still apply to a 4-stroke?

Sure, the dynamic balance should be really good, but overlaying this with staggered power pulses makes the net result a bit less clear.

Why would the "power pulses" be staggered?

 

[Cache Man]

There are several small three cylinder engines that may work. The question is... would the Manufacturer sell them to Elio?

Here is a review of the 1.0 Ford 3-cyclinder in a Fiesta. The car is just under 2,600 lbs and it sounds like it performs well. The review states that the MPG never dropped below 40/MPG even when pushing it. Cool.
http://www.roadandtrack.com/new-car...8611/road-test-2014-ford-fiesta-sfe-ecoboost/

 

[Ekh]

Yikes! I feel like I'm being whipsawed by the variety of topics in this thread!

Back to the OT for a moment, I thought I read somewhere that the Elio engine had a 120-degree crank, giving it a smooth(er) operational cycle than the 180-degree, 2-1 crank that would be more typical of a "bandsawed" 4-cylinder.

I know a 3-cyl, 2-stroke is very smooth, getting evenly-spaced firing pulses, but does this still apply to a 4-stroke?

Sure, the dynamic balance should be really good, but overlaying this with staggered power pulses makes the net result a bit less clear.

Friday was a non-event, so we're having non-relevant conversations! Threads always seem to break down when their central purpose is exhausted or made irrelevant. But the succeeding chatter can have its positive side ...

 

[Ekh]

Elio's answered the "why build our own" many times. The short version is that existing engines did not provide sufficient torque to deliver the specified mpg at highway speeds, so significantly longer stroke was needed.. It was also, and I have this from jerry Vassallo last summer, an economic decision -- actually cheaper to design and make their own. I questioned this, and he said, "it's complicated, but it really does work out that way," or words to that effect. Light, strong, torquey, and cheap to manufacture, but sufficiently durable. That's a challenge, and existing engines didn't meet it. It might help us if we stopped thinking "Metro" and started thinking "modern, specific to the task at hand." That kind of changes one's whole perspective on this issue.

As I said earlier in this thread, making darn sure there are no problems from harmonic or anharmonic vibration or oscillation is an important part of engine testing,or, if there are, being able to damp the resonance out by adjusting the engine mounting points is prudent ... and obviously means that the engine testing has to be complete before construction of the chassis begins. Personally, I think if the funding were there, we might see progress towards non-engine-mount related parts of the bodies, but as it is ... it costs less to do it right than to do it over again.

 

[Rickb]

Full face was a choice, put the cervical vertebrae break applied to all helmet types.
But, if you demand "brain buckets", why would you let someone ride in a pair of "cut offs" and "flip flops"?

I think the primary concern is to protect the brain irregardless of the bad MC fashion choices it makes. If I inadvertantly cause an MC accident that causes the rider serious injury or takes a life that could have been prevented by wearing a helmet I agree with mandatory helmet and/or seatbelt laws. I care less about scraped skin and discomort while healing as the result of wearing flipflops or cutoffs while riding, or serious sunburn.

Even the Son's of Anarchy wore helmets.

 

[Johnapool]

Elio's answered the "why build our own" many times. The short version is that existing engines did not provide sufficient torque to deliver the specified mpg at highway speeds, so significantly longer stroke was needed.. It was also, and I have this from jerry Vassallo last summer, an economic decision -- actually cheaper to design and make their own. I questioned this, and he said, "it's complicated, but it really does work out that way," or words to that effect. Light, strong, torquey, and cheap to manufacture, but sufficiently durable. That's a challenge, and existing engines didn't meet it. It might help us if we stopped thinking "Metro" and started thinking "modern, specific to the task at hand." That kind of changes one's whole perspective on this issue.

As I said earlier in this thread, making darn sure there are no problems from harmonic or anharmonic vibration or oscillation is an important part of engine testing,or, if there are, being able to damp the resonance out by adjusting the engine mounting points is prudent ... and obviously means that the engine testing has to be complete before construction of the chassis begins. Personally, I think if the funding were there, we might see progress towards non-engine-mount related parts of the bodies, but as it is ... it costs less to do it right than to do it over again.

The one good reason for the occasional Metro mention is this- that little engine is still reported to be a good one, lasting a long time with minimal repairs. It is not an "interference" engine, even though it has a timing belt.
So, it is a good example of a successful three cylinder, four cycle automobile engine that was used for many years and still runs on our highways.
Of course EM has designed an improved engine that fits their particular niche. No question about that. It ought to be a good one.

 

[Jim H]

FYI: https://www.iav.com/us/about-iav/clients

Didn't see Elio on the list, did I overlook it?

 

[Kuda]

Didn't see Elio on the list, did I overlook it?

No, they aren't there. Website update?

Elio is mentioned in one of IAV's press releases:

http://www.utsandiego.com/news/2014/oct/02/elio-car-three-wheels-and-shoestring/

 

[John Painter]

Didn't see Elio on the list, did I overlook it?

If they update their website as often as my agency does then we'll see Elio listed in a few years.