Quote:
Originally Posted by 3-Wheeler
I presume from your later posts, that you are referring to getting super high mileage from 4 wheels.
To be honest, I think that my Insight, which typically gets 120 mpg in the summer months, is a gas hog.
Why?
I weigh close to 190 lbs, and I need "transportation" to get my body from Point A to Point B.
The Insight weighs in at 1900 lbs, so right off the bat, the ratio of my weight to the cars is a low 1:10 ratio. The Insight engine has to "haul" 10 times my body weight just for the "luxury" of me riding in a "car".
Naturally the progression then becomes, "how do I move myself from one location to another without moving so much mass".
A motorcycle or scooter comes to mind. And then the next question, how much horsepower is required to make this happen.
Craig Vetter seems to feel that his 17 hp Honda step-through has the right balance between weight and hp.
Obviously, a more efficient approach would be a HPV bicycle, but I assume you are not discussing this type of motivation in your vehicle.
Jim.
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Hey Jim,
While my intention is to prove that 1 Liter fuel consumption is very possible in a purpose built car as opposed to motorcycle. I am a big fan of the reverse trike 3 wheeled designs and have spent much time on learning about them and helping build them. It is my opinion that a 3 wheeled design when it relates to fuel economy and achieving 1 Liter performance has many advantages over a 4 wheeled platform.
My Tigon hybrid initially started out as a reverse trike but as I have moved farther along I have changed things up to the traditional 4 wheeled platform of the original car. My reasoning was that I felt a 3 wheeled design is better fabricated from the ground up rather than modifying a perfectly good light weight chassis. I also want to keep things as simple as possible so that I can offer people full body bolt on kits for there Spitfires and GT6 chassis in the event people actually like it and would like to replicate and or modify TIGON. They will have the body kit and a detailed plans of the original prototype as well as my help if anyone wants it while working on there own copy.
To get back on topic here what Mr. Vetter is doing I think is great and is what I would like to do but with 4 and 3 wheels. Much can be learned from Mr. Vetter and his contributions to high mileage fuel consumption. Much of it can also be applied as well to 4 and 3 wheeled purpose built and or modified platforms. 17 to 20 hp ICE is what he has deemed as ideal for his applications. I believe that it can be much less with a hybridized drivetrain solution further reducing emissions and fuel consumption. If we drop to around 13hp this gives us enough power to propel a 1,200lb vehicle with low aero of less than .2 85mph with the correct gearing on fossil fuel only. That is more than enough speed to be sufficient here on US freeways.
Now hybridize the small say 2 cylinder or even 1 cylinder and you will have much better acceleration and low end torque for hill climbing and or passing situations than you would with a 3 cylinder 17 to 20 hp ICE engine. It also gives you huge advantages while in the urban environment stop and go traffic which the 3 cylinder can not achieve on its own.
The key is to determine your ICE only top speed then figure out what is the smallest ICE engine you can get that will achieve it comfortably and still be extremely reliable. I have found that around 13hp will comfortably allow 65mph and 85mph pushing the little 2 cylinder diesel nearly to its rpm 3,600 limit. Next optimize it meaning take everything off of it you can that robs HP and hurts engine efficiency such as what they did with Ken's Fiat 600 during its race days. Those accessories can be relocated, modified, combined, and hybridized themselves for greater efficiency and control. Next Hybridize the entire drive train and optimize it for fuel economy. Then once this is done optimize the rest of the vehicle such as eliminating weight down to its practical safe limits preferably 1,200lbs or less, cleaning up the Aero preferably getting under the .2 mark and reducing rolling friction as well as reducing unsprung weight!
In a nut shell this is the 1 Liter fuel consumption strategy and is what will get you to that mark but we need to explore and go into much more detail hence is why I started the thread.
GH..