The Elio Engine

[Snick]

Yep, seems to show 2 phase intake, such as for activating Atkinson cycle under part loads. Activation mechanism not shown in animation, but 2 lobes clearly visible on intake valves.

 

[outsydthebox]

Yep, seems to show 2 phase intake, such as for activating Atkinson cycle under part loads. Activation mechanism not shown in animation, but 2 lobes clearly visible on intake valves.

IIRC, it was recently stated that it would not be a "variable valve timing" engine.

 

[NSTG8R]

If the drawings released in Spring 2014 are true, then they will have variable cam phasing (2 step). So...not Geo Metro cam.

Hmmm...I'm no expert on variable cam phasing, but after watching the CAD video a couple of times, I can't see how the timing will vary with the cam gear 'hard mounted' to the cam shaft...unless, of course, the cam is hollow (would have to be with cam phasing anyway) and the actuator is that doohickey at the opposite end. Haven't seen any drawings of the engine as yet, or a configuration with the actuator anywhere but on the timing belt/chain side of the cam. Then again, I work on jets, not cars.

 

[NSTG8R]

Yep, seems to show 2 phase intake, such as for activating Atkinson cycle under part loads. Activation mechanism not shown in animation, but 2 lobes clearly visible on intake valves.

I'll be damned, I didn't see the double intake lobes until you mention it....Good call!

 

[wheaters]

I'm intrigued by the contradictory information being put out about this engine.

The Suzuki G10 (Geo Metro) 993cc engine, which is the engine in the Elio prototypes, has single point fuel injection and non-VVC cam timing. The inlet manifold is optimised for good emissions and fuel economy rather than for power output. To be blunt, it's very poor for airflow. It produces 52hp, which is quite poor even for an older engine of that size. To get more output, more airflow is required. I know someone who has inadvertently discovered this. He has converted the G10 in his trials car to non-sequential, multi-point fuel injection but kept the original manifolds. He put a lot of time into the project, thinking it would give more horsepower. It gave no improvement whatsoever. Not really surprising, same airflow = same output, irrespective of how you control the fuel input.

The Elio engine, which appears to be basically very similar, but with manifolds designed for better airflow, is posted as giving just 55hp. This would suggest that the cam doesn't have VVC. The Toyota Aygo 1.0 engine, which does, gives 70hp.

However, the Elio is also posted as having sequential fuel injection and a "dry" inlet manifold, via intake port injection, which is probably where Elio are hoping the better fuel economy will come from. Certainly there is nothing "trick" about the combustion chamber, looking at the latest photos of the castings they intend to use.

Sequential fuel injection requires a cam position sensor. The Suzuki doesn't have one (I have made one for my own engine which I'm converting to sequential fuel injection using triple throttle bodies and rear wheel drive for my Liege).

I'd conclude that the round "lump" on the non-driven end of the Elio engine is probably a cam position sensor, not a VVC control.

 

[ArthurKent]

I'm intrigued by the contradictory information being put out about this engine.
The Elio engine, which appears to be basically very similar, but with manifolds designed for better airflow, is posted as giving just 55hp. This would suggest that the cam doesn't have VVC. The Toyota Aygo 1.0 engine, which does, gives 70hp.
However, the Elio is also posted as having sequential fuel injection and a "dry" inlet manifold, via intake port injection, which is probably where Elio are hoping the better fuel economy will come from. Certainly there is nothing "trick" about the combustion chamber, looking at the latest photos of the castings they intend to use.

I'd conclude that the round "lump" on the non-driven end of the Elio engine is probably a cam position sensor, not a VVC control.

If this poster had done some research, he would have learned that the Elio IAV engine can be tweaked,
if desired , to achieve 70 HP. And more if direct injection were to be used (won't initially - too high a cost).
The driving motivation for the Elio is low initial cost and low fuel costs, which rules out forays into the poster's world of
hot rodding. There has been company-sourced talk of a turbo version of the engine (current IAV design not beefy enough to handle the increased pressures). That would be the way to produce a pocket rocket version of the Elio, not twiddling with intake design and fuel injection technologies, which can, at best, only produce meager power upratings.
I might add that, after looking at the acceleration figures for the very similar Morgan three wheeled retro car being produced these days, that a 1200 pound vehicle (like both the Elio and Morgan) with an 82 HP engine (like the Morgan has) can provide very quick acceleration (0 to 60 in under 6 seconds). An IAV turboed engine could easily make 82 HP, and more.
The Elio doesn't have, doesn't want VVC. The Elio engine can be tweaked to get 70 HP - that was from the designer, who know a great deal more about this engine than this poster, wh mentions "confusion" abut this engie,

 

[eddie66]

http://eliomotors.wordpress.com/2014/02/21/engine-qa-with-iav-2-21-14/

 

[NSTG8R]

If this poster had done some research, he would have learned that the Elio IAV engine can be tweaked,
if desired , to achieve 70 HP. And more if direct injection were to be used (won't initially - too high a cost).
The driving motivation for the Elio is low initial cost and low fuel costs, which rules out forays into the poster's world of
hot rodding. There has been company-sourced talk of a turbo version of the engine (current IAV design not beefy enough to handle the increased pressures). That would be the way to produce a pocket rocket version of the Elio, not twiddling with intake design and fuel injection technologies, which can, at best, only produce meager power upratings.
I might add that, after looking at the acceleration figures for the very similar Morgan three wheeled retro car being produced these days, that a 1200 pound vehicle (like both the Elio and Morgan) with an 82 HP engine (like the Morgan has) can provide very quick acceleration (0 to 60 in under 6 seconds). An IAV turboed engine could easily make 82 HP, and more.
The Elio doesn't have, doesn't want VVC. The Elio engine can be tweaked to get 70 HP - that was from the designer, who know a great deal more about this engine than this poster, wh mentions "confusion" abut this engie,

Ouch Arthur, not sure what our UK friend said that hit a nerve, but it does sound (to me) that he knows a little something about subject. And thank you Eddie66 for the link.

 

[Snick]

Arthur and Wheaters,

Why do you suppose the animation shows dual intake cam lobes? Was it just a mistake in the 3D model?

 

[wheaters]

Well, Arthur, you must be a real engine expert.

I'm not, but I have been building and modifying any different engines since the 1970s. I'd consider this (and having built a car to put them in) my main hobby. I used to teach piston engine theory in my former career in the Royal Air Force, so I have a fair knowledge of most issues affecting engine design and output.

I have two Suzuki G10 engines in my possession, one of them in the original car, which I use, and one which I am in the process of modifying for more output. These are as close as anyone can get to the IAV / Elio engine. So I feel fairly well able to comment.

My only confusion about the IAV (as in the first line of the post you quote) is about the contradictory information being put out by Elio.

I'm aiming to obtain 60 to 65 hp from my modified Suzuki G10. Different cam, higher CR and port work with sequential injection and a more efficient inlet system and a free flowing exhaust. This compares reasonably well with the 70 hp originally quoted by Elio. No turbo or VVC needed. 135 hp/tonne is more than enough for my purposes. Suzuki produced a turbocharged version of the G10 which had an output of 82 hp, which gives an indication of what Elio could achieve if desired. But not with 84 mpg as the main selling point.

If you have useful advice rather than unwarranted criticism then I'd be delighted to hear more from you.