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UBC Engineers Reach Mileage Of Over 3000 MPG
The New Revelation writes "Physorg reports that engineers at UBC have developed a single occupancy vehicle that achieves a ridiculous 3145 MPG! From the article: 'The Society of Automotive Engineers (SAE) Supermileage Competition took place June 9 in Marshall, Michigan. Forty teams from Canada, the U.S. and India competed in designing and building the most fuel-efficient vehicle... The UBC design, which required the driver to lie down while navigating it, achieved 3,145 miles per US gallon (0.074 liters/100 km) -- equivalent of Vancouver to Halifax on a gallon (3.79 liters) of gas -- costing less than $5 at the pump.'"
Competition results, warning PDF http://www.sae.org/students/sm2006results.pdf
Indiana and a HS there too came in with high MPG, as did Laval in Quebec province.
Saskboy's blog is good. 9 out of 10 dentists agree.
According to the rules they were required to have an average speed between 15 and 25 mph (24-40.23 km/hr). They drive six laps for a total of 9.6 miles (15.5km).
From the official rules:
40.1 Minimum and Maximum Speed Requirement
The performance run will consist of each vehicle running six laps around a 2.6 km (1.6 mile) oval test track. The vehicle must achieve a minimum six lap average speed of 24 km/hr (15 mph). This means that each vehicle will be required to travel a total distance of 15.5 km (9.6 miles) in a maximum of 38.4 minutes. The vehicle must not exceed a single lap average speed of 25mph (40.23km). This means a vehicle must take longer than 3 minutes 50 seconds to complete each lap. Vehicles must be capable of ascending a 1 percent grade and descending a 7 percent grade.
40.2 Slow Speed Penalty
If the minimum average speed of 24 km/hr (15 mph) is not maintained, a penalty will be assessed by subtracting from the km/liter (mpg) achieved, 4.25 km/liter (10 mpg) per second of time that the minimum average speed requirement is not met. For instance, if 39 minutes was the elapsed time for six laps, the minimum allowable time, without
©2004 SAE International 20 2005 Supermileage
penalty (38.4 minutes) was exceeded by 36 seconds. The actual mileage achieved would be reduced by 153.1 km/liter (360 mpg).
40.3 Maximum Speed Penalty
If the maximum lap average speed of 40.23 km/hr (25 mph) is exceeded, a penalty will be assessed by subtracting from the km/liter (mpg) achieved, 4.25 km/liter (10 mpg) per second of time that the maximum average lap speed requirement is not met. For instance, if the third lap was completed in 3 minutes 12 seconds, the minimum allowable time, without penalty (3 minutes 50 seconds) was exceeded by 38 seconds. The actual mileage achieved would be reduced by km/liter (380 mpg).
40.4 Start
Prior to the performance run, an official fuel tank (supplied) will be filled, weighed and installed on the vehicle. The start of the performance run will begin with the vehicle being placed on the track starting line. The vehicle engine is then started, either by the driver or his pit crew. Timing for the minimum speed requirement starts when the vehicle crosses the starting line. Vehicles cannot be push started. Transmission design must be such that the engine can be disconnected from the driving wheels so as to allow the vehicle to be stationary with the engine running.
40.5 Finish
Upon completion of the six lap performance run, 15.5 km (9.6 miles), the timers will record the elapsed time; the fuel tank will be removed and weighed. The kilometer per liter (miles per gallon) calculation for the vehicle will then be computed, dividing the 15.5 km (9.6 mile) distance by the amount of fuel used. If the maximum allowable elapsed time has been exceeded, the penalty will be computed and subtracted from the kilometer per liter (miles per gallon) calculation.
They go something like 15mi/hr. They turn the engine on and get up some speed then turn it off and coast a while. They use Briggs and Stratton four stroke lawnmower engines with custom machined cylinder heads and such. Of course the cars are basically like bicycles with aerodynamic fairings on them.
Well the veacles are only required to be able to climb a 1% grade (and decend a 7% one) at an average velocity between 15 and 25 MPH so it wont get you where your going very fast, or through hills.
All misspellings and grammatical errors in the above post are intentional and part of my artistic expression.
4 cycle does not mean 4 pistons. It's a reference to how many times the piston moves to make a complete "cycle". In the case of a 4 cycle, it fires once every 2 times it goes up. A 2-stroke fires each time the piston is up.
Basically they took a Makita 54cc (3.3 cubic inches) engine off a chainsaw (capable of doing 12,000 rpm) and hooked it up to a chain/belt and used that.
-- Knowing too much can get you killed, but knowing who knows too much can make you rich.
Dear esteemed /.'ers
/. ...many would just look at the intro and conclusion sections of a report. We didn't provide too much detail so as not to bore. :)
/. but we're honoured. Keep the discussion (criticism) flowing.
:P Ah well.
I'm a member of the team (Charlie Yao) and thought I'd give some clarifications to what seems to be common questions.
Methodology of competition:
Basically, you're given a topped off fuel bottle and you run 6 laps around the track (with other vehicles running simultaneously). Afterwards, they remove the fuel bottle and measure the amount you consumed (by weight). Do some math, you get your efficiency.
Speed requirements:
The rules state between 15-25MPH. In practice, with 6 laps, you're given a time frame in which to complete it. If you go out of this time frame, you're penalized heavily. The max time is 38.4 minutes. The min single lap time is 3min 50s. Obviously, we care more about the former.
Driver orientation and details:
The driver lies down on his back, feet first. He still has his head tilted up so he can see... imagine standing and looking at your feet. Only drivers of a max height can fit since our vehicle is specifically designed for one. The minimum weight of the driver is 130lbs and ballast is added otherwise.
Litres/100km:
On typical vehicles, quoting km/l gives unwieldy numbers (so I hear, I'm neutral) so instead they use litres per 100km. For us, the reverse applies... 1337km/l vs. 0.074 litres/100km. And yeah, it was amusing to get 1337 performance. FYI, you can do multiple runs on the track (one team got in 8 while we got in 4) and our mileage varied from about 2900-3145 MPG. They take your best result.
Safety and practicallity:
No, it is not safe on the road... not with typical road vehicles. It is relative of course since those who choose the more fuel concious cars get screwed by SUVs. If everyone drove small cars, it wouldn't seem as dangerous would it? There actually has been an incident in the past where a student has been killed while testing on a highway. I believe it was in Ontario and maybe by U of T but I'm not certain. As for practicallity, no, it's not... but neither is any car designed for performace. Look at an F1 car and tell me where you're going to fit your family.
Info missing from TFA:
1) Not everyone is as inquisitive as
2) We have to keep some of our secrets away from our competitors
I'll check back to this thread every so often and try to reply to the best of my ability. I'd just like to add that perhaps the biggest value is educational. There's been a lot of innovation especially since we don't have the largest budget. Teams that have to travel substantially shorter distances to the competition have trailers for their vehicle, tools and extra cars for their members. We travel in one minivan and literally duct tape the car to the roof. If we can't find some more sponsors for a trailer... maybe we should get some from 3M. Also, there are teams overseas that get 3-4times our mileage... basically professional teams with relatively unlimited resources. They also generally don't have engine requirements.
Either way, it's been a great ride. It's eery to be on
Cheers,
C
P.S. Unfotunately the team pic didn't work out in my favour. I was using my shirt to hide oil stains from working on the car but it looks like I really need to go to the washroom
Almost all designs have drivers lying on their backs. When I was in college, we were the only team to have a head first design with the front axle (w/2x700mm bicycle tires) above the drivers torso, arms in front, and his feet went on either side of the rear drive wheel. Although there is no express rule prohibiting it, the people running the competition thought our design was unsafe (huhh) and forced us to retire the chassis after 2 years.
Having driven before I can say that they pick the smallest guy on the team (must ballast up to 150lbs I think) and cram him in. No air flow, hot, loud, and no fun - definitely no DVD player. You burn to get you speed up, then coast. You can run as many times as you want and take the best run, you just have to wait for your rotation.
As mentioned by previous posters, Briggs is a sponsor so teams are requires to use a Briggs&Stratton engine. Most teams only use the case (required), replace the shell bearings with balls, de stroke it and sleeve it to a smaller displacement (we used a Honda piston & rod), make a new head with overhead valves (the Briggs is an L head). During are first years we used a modified stock ignition and aftermarket carb but by my senior year we had a pretty sweet ECU with fuel injection (we re-calibrated a GM ECU). Most drive trains at the time were chains to a pillow block with a centrifugal clutch. The total engine/chassis weighed like 80lbs.