1 Liter Performance How to guide (1 L/100 km = 235 mpg US)

[darcane]

Originally Posted by GreenHornet

After performing a quick internet search I located the current owner of this vehicle and his detailed website about the car and its history. Inside the website you will find information about the car in addition to others that were built and raced in the Shell Eco marathon races. I found the site to be extremely informative and will pull data from it to discuss the vehicle as I move along.

Owner = Ken Smith
Website = Home - Shell Fiat
Article Link with great pics = Shell Eco-marathon: 1959 Fiat 600 brings hypermiling history to Houston

I would like to thank Mr. Smith for deciding to share his car with all of us through his website as well as all the information he has collected on the car through researching and talking with the original designers themselves. I hope to contact Mr. Smith at some point to discuss the car further as well as the conditions that were present when the car broke the 1 Liter fuel economy mark.

GH

With all the research he's done, he should write a book. A Shell Eco Marathon coffee table book would be kinda cool.

[RiderofBikes]

Width = 1,380 mm (54 in)
Height = 1,405 mm (55.3 in)

Well, you do have the Fiat 600 hieght and width dimensions listed above so...

55.3" * 54" = 2986.2in

4.06' * 4.5' = 18.27ft, +/- .5 for wheel area...

[Xist]

Originally Posted by tjts1

walk

Way off!

Ride a bike!

[GreenHornet]

Shell Fiat 600 car Modifications list:

From general reading in the links I provided about the vehicle I have a list of essential modifications to the car that helped enable it to get 1 Liter fuel economy at low speeds.

#1. No alternator.

#2. No water pump replaced with Electric fuel pumps (2) to pump the water.

#3. No radiator a small heater core was used instead.

#4. The engine and transmission were insulated to hold the heat during the race.

#5. Shocks were removed and solid suspension was installed.

#6. Taller tires were installed to reduce wheel speed to drop engine rpm.

#7. Carb capacity was reduced. Accelerator pump use was removed.

#8. Hotter ignition was installed to overcome leaner air/fuel mixtures.

#9. Suspension was stablized to remove excessive movement (causing energy loss).

#10. Tires were over inflated for less rolling resistance.

Anyone that can provide updates and additions to this list feel free to do so. The technical paper Mileage Marathon from 50 to 244 mpg has a very detailed overview of the Fiat and all of its modifications. I have located the paper here = Mileage Marathon from 50 to 244 mpg

I may end up getting it just for the heck of it. I think it would be a good addition to the library and a compliment to the book fuel economy of the gasoline engine which is invaluable with tons of details on how to achieve high fuel economy which I all ready have on the shelf.

[KenS]

Originally Posted by GreenHornet

The first car I would like to analyze and discuss is the 1959 Fiat 600 that competed in the Shell Eco Marathons and achieved verified fuel economies of 173 mpg in 1967, 244 in 1968 and 304 in 1973.

This car may or may not have been previously covered in this forum if not I would like to perform an in depth analysis of the car and just how it achieved its 304mpg back in 1973.

First lets look into the 1959 model year Fiat 600 car specs.

Basic Specs:



Class = City car
Body style = 2-door sedan
Layout = RR layout
Engine = 633 cc OHV I4
767 cc OHV I4
843 cc 100 R7.038 OHV I4 (600S)
Length = 3,215 mm (126.6 in)
Width = 1,380 mm (54 in)
Height = 1,405 mm (55.3 in)
Curb weight = 585 kg (1,290 lb)
CD = 0.5
Top Speed = 61mph
MPG = 41.2

Now we know the basic specs of the Fiat 600 next we need to determine what engine was used in the Shell Eco Marathon version as well as any modifications that were done to enhance the baseline 41.2 mpg of the original.

Hey group. The Fiat has a 633 cc engine. Stock block and head. The intake system was converted. The exhaust was stock also. Carburetion was changed to improve the fuel dispursement. The air was passed over a 50s Ford car heater core to heat up the intake air as well as cool the engine coolant running through the engine. The original water pump, fan, radiator, and alternator were removed from the car. The engine was run like a hypermiler would run his engine in a serious mpg race. In otherwords, the engine did not run 100% of the driving experience. In looking back at the photos of the car as it was raced, the engine compartment was covered with insulation. When the engine was stopped and the car coasted, the insulation would help keep the engine warm for a restart. This, being one main reason the results were so good, would not be practical for street use today. All and all, the original Shell Mileage Marathons were raced by vehicles of original size and weight. More real than the Eco Marathons of today. Respectfully to the ECo races, the young people of today actually racing those cars could and can be the leaders of mileage gains tomorrow. I have had a great time visiting the Eco Marathons in Houston, Texas the past three years. Lots to see and learn from.

[GreenHornet]

Hi Ken and welcome to the forum. Thanks for taking the time out to drop in and share more about your incredible Fiat with all of us.

It is not a surprise to me that the 633cc engine was utilized out of the 3 engine options that were available at the time. The intake system and the carb was also optimized which would make sense.

I think what people do not quite understand here is that your car while from the exterior is still 100% Fiat Under the hood was a much different story. While the car achieved 304mpg at low speeds my educated guess is at speeds averaging between 25-30mph this is still quite remarkable and could never have been achieved without the laundry list of system modifications. This Fiat was a highly modified and tuned car that had 1 mission and that is high mpg.

Now to put this into perspective we are talking about a car that from 1959 and had a curb weight of 1,290 lbs, a 633cc gas engine, CD estimate of .5, and was rear engine rear wheel drive. There was no carbon fiber composite, no light weight alloy or magnesium wheels, no aerodynamic detail such as wheel well covers, boat tail etc, and no hybrid components what so ever only ICE!

Now lets fast forward and look at a modern family of cars that have achieved verified 1 Liter fuel consumption. I am talking about the VW 1 Liter cars. Initially the prototype was a 299cc 1 cylinder turbo diesel and has sense with its updated version moved to a 2 cylinder electric hybrid drive train. All 3 iterations were reported as achieving 1 Liter fuel economy with greatly reduced emissions the latter being the most potentially fuel efficient at a combined 310mpge and extremely low emissions output of 24g/km.

Why I dropped the VW family of cars into the mix is so we can see the progression from 1959 to now 2013. As you can see the original Fiat 600 hypermiled car while being much more basic still needed to be heavily modified and take advantage of reduced curb weight and small engine displacement to help achieve its 304mpg. All the VW cars share these same traits low weight and highly modified.

What is still a bit unclear is at what speeds did these cars achieve there 1 Liter performance?

Based on books I have read on the Eco Marathons during 1959 and later it is my educated opinion the Fiat was drove at average speeds between 25 and 30mph.

Now the question I have is with the VW family of cars. With there advanced hybrid design and other modern advanced technology were they able to achieve 1 liter fuel economy at modern real world speeds between 40 and 60 mph and under real world conditions not simply driving around a test track counting laps?

This is one of the many questions I hope to answer here in this thread as we dive deeper into the world of 1 Liter performance

GH..

[GreenHornet]

Originally Posted by darcane

With all the research he's done, he should write a book. A Shell Eco Marathon coffee table book would be kinda cool.

Yes this would be really cool and one book I would definitely purchase. Ken take note on this as you have the great opportunity to put something like this together. One could also incorporate other cars from that era such as the Shell Opel car and 1947 Studebaker then progress into the modern cars we can see at the Shell Eco Marathons currently. Another very cool point is that the original designers of the Fiat can be interviewed and implemented into the book as well as others who worked for shell back in those days. This would greatly add to the books value as not only a cool book but a piece of automotive history. Before and after pics can be offered as well as technology, modifications, and overall design can all be discussed.

I think every eco-hypermiler would want a copy of this book as it would represent a great look into our past roots so to speak and create great exposure to the ecomodder movement around the globe

GH

[GreenHornet]

Some other valuable info that I will dig into on the Fiat are tire info stock and modified as well as tire pressure info which I believe I have in one of the books or articles I have laying around. Other info that would be great to uncover is stock transmission and differential gear ratios and if they were modified in any way for the races. If they were left stock I think this could also have been one area for further improvement they could have exploited. So I will try to do some digging on this and get something posted on these facts in the next post.

GH

[3-Wheeler]

Originally Posted by GreenHornet

If a person wanted to try and achieve 1L fuel economy (282 mpg Imperial) how would they do it?

That is what this thread is going to attempt to answer

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.

[Vekke]

Green Car Congress: XL1 dive and drive: Volkswagen aggressively optimizes for efficiency in its sleek diesel plug-in hybrid

If XL1 needs 8.3 hp at 100 km/h you can calculate the fuel consumption with few rough assumptations at that speed and it will be 1.8-2.2 liters.