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Originally Posted by RobertSmalls
I took the time to watch the videos. They left me wanting to hear more technical details. Specifically, what is the drag coefficient and frontal area of the car? You can't tell from the first two videos, but the top half looks very low drag. I can't see the bottom half very clearly, nor do we know where the wheels go yet.
The Suzuki 1.0L 3cyl is not a bad power plant, but I absolutely love Honda's lean-burn capable 1.0L 3 cylinder, which comes with regenerative braking and electric assist. A donor Insight will also provide you with dozens of lightweight components you can use, breathable seats, electric power steering, LRR tires, a futuristic gauge cluster, and maybe some ideas about how to improve efficiency.
I like the location of the taillights. As long as the leading surfaces follow streamlines, they should contribute only a little drag. You could eliminate the leading surfaces for better aero at the expense of aesthetics. I wonder if narrow rear wheels on outriggers, with lights mounted on them, would be a viable solution for a car with a narrow body and a wide track.
I share Frank's cynicism regarding the fuel economy of the car. I completely doubt you will double the thermodynamic efficiency of an engine where Suzuki's engineering teams failed to do so.
The problem of achieving maximum engine output per unit fuel is one completely seperate from that of building an efficient body. If you have a cost-effective design with amazing efficiency, prove it on a bench dyno and sell it for tens of millions.
As for the amount of energy required to move the car a mile, well, as Frank said, tell us your CdA and Crr, and I'll tell you your mpg @ any given BSFC. Let's see some numbers and measurements to back up those wild claims!
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Hello,the frontal area caculations i did were done using a front view photo of the car place onto some graph paper and scaled to size.I know this might have some inaccuracies associated with it so i will make a pattern that fits the frontal cross section of the body and count the square inches out for you guys so you can do the math.I am busy with work this weekend so i will go out to the car once i am caught up with my work . I used the Suzuki 3 cyl because it has the turbo on it.I wanted to be able to play around with the pressurized intake track.Once the car is built and driving with an established baseline and the efficiency boosted as much as we can.Then the goal will be to improve on those numbers with whatever drive system shows promise in obsoleting the Suzuki.This is a multiphase project . I must first build the car .I feel the Suzuki 3 cyl is a good starting point.If you look closely the front wheels are on the car in the videos.The body gradually swells out around them in the front,while the rear tire is placed up under the rear most portion of the body.The lower portion of the body from the front of the doors and rearward is a reverse boat hull shape.The underbody pan will be formed when i can mount the whole car to my rotisory and flip the thing over.I don't care for the outrigger idea ,in my mind it interferes with aesthetics and the flowing lines of the body.I believe the wings are necessary for the look i want the car to deliver.I will try to keep the drag to a minimum ,as there is a design adjustment in that area.Fuel economy of this car will be the best i can get it to be.That aspect of the car won't happen til the car is completed and baseline tested with a fresh engine.Then i will throw the engine mods at it.Then i will address the thermal efficiency improvements.As far as body efficiency goes ,i started with a perfect tear drop and then made contour changes for fit and appearance.This thing needs to be practical with as much efficiency as that will allow.The standard ICE is 20% thermally efficient,or 80% of the energy in the fuel is lost, to exhaust heat38%,water heating36% and 6% to friction.With 20% efficiency it nets 57mpg.If we can recover another 20% of that lost 80% don't you believe the mileage would double? We still have 60% lost to the enviroment at that.Aero mods are a huge contibuter to the mileage.I read a study done by a university in the Netherlands on bicycles. They compared the energy required to pedal a standard upright bike at 40 kmh (622 watts) to a recumbent bike with a full hard fairing (75 watts).That is a huge reduction in energy required.Some of these aero modded cars i have seen are claiming a 38% improvement in fuel economy.So i estimate with a 20% thermal energy recovery and this 38% aero related gain the mileage would be 157mpg.But i feel the three wheeler will net more than that.I could be totally wrong but i am going to build this car and find out.Proof is in the pudding the rest is all just theory and speculation.Thanks Zoltan.