This weekend, I’ll be taking the Monte Carlo on an economy run with other members of the Saab Car Club here in Tasmania.
It’s the first club event that car’s been on, actually, so I’m really looking forward to it. I’m not sure if there are prizes involved, but I believe it is a competitive event – aiming to use as little fuel as possible ever the 150km or so of driving we’ll do.
I’ve had a read over WooDz’s guide to driving for mileage, and I’ve got myself used to the idea of cleaning out ALL the clutter, staying within the first 3rd of the turbo gauge and slowing well in advance of a light.
But if anyone else out there has some experience with this type of one-off event and has some tips for a first-timer, please feel free to drop your advice in comments.
At least we get a free lunch!
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Try to drive without ever using the brakes – as mentioned before accelerate as slowly as possible and stop slowly, switch off gear in advance instead of stopping at the last moment, do not go over 3000 RPM, etc. And of course, if you want to get a good mileage – buy a diesel
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When I drive from work, I sometimes get caught up in traffic at the top of a hill.
Lately I have experimenting with turning off my engine and simply rolling down. It slopes sufficiently to allow me to keep up with traffic.
However, the brake booster eventually (but not right away!) gives up, so I have to press hard on the pedal whenever I want to stop.
I have not done this often, because at first it was a bit unnerving to use force to stop the car. Last time I rolled for five minutes or more… At the end I shifted into third and rolled the engine into action again. (probably not advisable, the engine strained itself a bit perhaps?)
And turn that air conditioner off! There was an episode of Myth busters, where they tried using air conditioner or driving with windows down – the air conditioned car had far worse MPG.
Didn’t they also turn the air conditioner on its lowest setting? The guy was seriously freezing?
And what about the efficiency of the aircon unit? Saab’s aircon is very sophisticated.
Plus Saabs are much more aerodynamic than the massive cars used in the mythbuster episode.
Oh… 150km? You need about 15 liters of gasoline. Leaving 45 liters of gasoline at home saves you about 30kg.
Not sure how that would affect mileage, but…
Also: Exercising! Reducing your own body mass by 10kg should also help.
Today I cycled to work. Leaving all sorts of things at home helped me burn less energy.
Air-con should be weighed up against maybe having the windows open which will cause drag. Swade won’t have to worry about turning the aircon off as it’s winter down under.
Having your engine ticking over in 5th when driving off a hill is far safer than tuning the engine off and mpg will be very high as the car is moving unlike being stationary and having the engine ticking over.
Make sure you tank with High grade fuel as it contains more energy and less will be needed to drive at comparative speeds. If you have 100RON then use it for this event it does make a different in MPG but not enough in my opinion to use on a daily basis. But this is competition time.
If that course is 150-200km you should be aiming to do it on between 11-15 litres of fuel. Consider that when filling the tank (64 Litre capacity) Would a third of a tank do the trick with over 5 Litres to spare? Try and do a ‘small’ test run tomorrow to see what you can achieve. 6,8Ltr/100Km? 7,5Ltr/100km.
Get that tyre pressure setup for the minimal amount of occupants too.
Turn off as many electrical items as possible. Air-con (mentioned above) , Headlights, food blender, radio, and only use the fan if required. Less consumption on the battery means less energy lost going to the alternator.
Use Cruise control as much as possible even for accelerating where you can. and do NOT go over 60mph!
OK I think that’s enough for now
10kg between now and Sunday!?!?
Ay carumba!
According to the table in the nice manual — this means reducing the tyre pressure.
This table helps you gain more comfort by letting your tires dampen the impact of the road, as well as increasing your grip on the road.
However, what we desire is reducing the rolling resistance.
We want the highest possible tyre pressure.
The table in the Saab manual reflects this, with an entry at the bottom which specifically says “most fuel efficient” or something to that effect. 41 psi as far as my wheels are concerned.
(In comparison, my mountain bike tires usually see around 60 psi… Less pressure causes noticable more wear on the rider, i.e. me)
Well, you might be able to loose a pound or two…
My dad (and some friends) swear by the Atkins’ diet btw. A diet consisting of not much than proteins and fat. There are indications that it also helps against diabetes.
Dunno if you will see results in so short time though.
Swade, have your wife to drive. That probably do the trick.
Oh I forgot one final thing
IMPORTANT: Have a great day!
Stay away from discount docket cheap fuel Steven. And you might be able to cheat a bit by using higher octane fuel then your competitors.
Do you still remember the kick up the butt when you accidentally got that really good fuel at the pump in the Viggen. Happened to me a few times at Ampol, but more frequently with BP. I even had the SID reading 1000km to empty once. And wheelspins in third onthat tank. :p
Ctm> lol:)
I almost forgot about Woodz tip about getting better MPG! will print it out now:)
i did drove from Västeras to Stockholm yesterday . That`s about 100 Km and i drove about 90-100km/h and had the 6th gear and the fuel consumption did go down. however i need to drive even further distances to get even lower consumption.
btw im on E85 also.
Swade,good luck on your journey & MPG-project and have a great time with your Monte Carlo:)
I’m just waiting for Swade to call me a goose.
and the other members of your home country saab club are not reading your blog?
stay behind some other car, as in aspiration, maybe you will get a few houndred meters more on the same fuel on an 150 km trip
Surely he would have to get pretty close to notice any positive effect from drag?
The safest approach is probably to line up behind a big lorry.
Alternatively: A grapple hook and 100m worth of rope.
…or his wife will soon drope a note here;)
Please read Saab engineer Olle Granlund’s article in Volume 21 of Saab Soundings, Better MPG the 1-3-5 Way on page 20. Some very counter-intuitive, but proven tips such as using full throttle in top gear.
tough call mate- for a Swade.An Alfa- Saab driver doing it economcially- nah…
Ease off on the gears, go from 3rd to 5th if you can. Dip the clutch downhill.Open up the cabin air vents and leave the hatchback closed but open on the catch so its still resting on its rubber trim.
Get those tyres up to 45psi.
Drive without using the brakes- if possible. But do not use gears to slow down- as the revs will rise early dn use fuel.
Look, i am a glider pilot, I know how to manage energy . Pretend you are gliding up to every stop and every junction or bend – glide the thing on dipped clutch if you have too. And lose some weight!
Overinflate by a bit. Drink less beer. Leave the heavy laptop behind. Remove back seat and spare tire.
Most importantly, have fun!
SU top tips, summary:
- super inflated tires with bulging sidewalls.
- Swade naked in the car
- no spare wheel, no extra gasoline
- lose 10 pounds in 1 week (makes point 1 better appearance)
Good luck, Swade!
Maybe I wrote about nudie runs too often a few weeks ago……..
+1 Ken.
Swade should definitively do a nudie run.
The news of this will encourage other participants to bring their cameras, thus adding weight to their own rides.
Less need to run the AC too.
Swade’s victory will be oh so sweet!
“Dip the clutch downhill.”
Actually don’t do that.
Fuel injection will cut off when there’s no load. Injection will restart below 1200 rpm (or so) to prevent stalling. You can feel it cut-in if you pay attention.
It’s counterintuitive, but modern cars don’t use any fuel when coasting in gear. Try to keep the revs below 2000 when doing this so that engine friction doesn’t slow you down too much.
Swade hope that You are the ONLY reader of this otherwise Your competitors might win!
You must start at a gasstation and have all cars filled to the max and at the finish repeat the procedure this will tell who is the winner, never trust the instruments in the car.
Key issues on economy driving contests.
- Reduce weight
clean out the trunk, books magazines maps, floormats, spare wheel,
- Reduce drag
Fold in the rear mirrors if legal, add more air to the tires, if possible put om the narrowest set of tires you got, tape the areas between hood and fenders etc. put flat discs on the wheels but only if You do not plan on to much breaking. Take away wings and spoilers on the back of the car.
Change drive style
Do NOT use the Cruise control (your foot is better) this id information from SAAB Test drivers at the factory.
Drive with an “egg” under the pedal
Do NOT exceed 65 km/h, Never exceed 2000 rpm
Skip 2nd and 4th gear if possible.
Good luck you will win!
Wow there’s some really good tips here.
And then there’s the darn right hilarious…
Love it
In my experience wives have heavier feet. Takes me days to bring average fuel reading down after Mrs Turbin drives.
Turbin,
Suppose You have not been a passenger to Mrs Turbin. Guess You do the driving when she is present. Let her drive and educate her, check all of the things to do and not to above.
It doesn’t work, at lest for Mrs Me. She always says it isn’t good for the engine to drive at low revs !! *GRRR*
At low revs, it does feel a bit uncomfortable, like the engine is about to burst at the seams or something.
I’ve never thought about it much before. Don’t know where to look really. But you guys say that at low revs the engine is efficient? How low? It tends to keep above 800-1000 rpms while idle. I guess there is a reason for that…
Put differently, if you strain it too much (e.g. going uphill in 3rd while
I’ve been a passenger to Mrs Turbin many a time, drag-racing a taxi in the wet in a 260kw V8 ute (pickup), another time sideways in same ute around around a wet corner, aggressive manouvres in both old and new combis. Speed is a relative thing, I drive too fast when driving slower than her usual speeds, when we’re in convoy I have to hammer the 9000 to keep up ; )
Average economy in the TiD is 5.7l/100km when I drive, 6.0+ when I get it back off her after a day driving the similar routes.
Low revs means to me changing to a higher gear so the car feels like driving on neutral, but if you then punch the throttle it doesn’t feel comfortable, at least with a diesel or the bike I had.
But the 1-3-5 tip above says that flooring the pedal (on low revs) is exactly what you should do.
In a hilly topology like Norway, is the 1-3-5 approach even feasible?
I almost tried it today, but I am very conscious about the traffic behind me. I do not want to cause bottlenecks.
In case you have a manual transmission:
Work the clutch on (slight) downhill slopes. That will keep your engine at minimum revolution, thereby saving energy that would go to friction otherwise (friction ~ relative speed between cylinder and wall). Your engine will not slow down your car.
Of course, you could shift to idle running, too, but that would not give you immediate control over the car.
Switching off the engine I would consider dangerous.
Since the brake booster deactivates you mean?
I thought about that too, but surely this is how the old cars work?
And such technology have been known to fail, so why not practice for such an eventuality?
In my case, rolling slowly down a hill for five minutes (or more)… Why bother with the engine? To keep pace with the traffic, I have to continue applying my brakes. Never do I hit the accelerator in this particular hill.
Hypermiling in any form will be a bottleneck… Sloooooow acceleration and caaaaaareful deceleration is not the fastest way (or at least not what most people tend to think is fastest – a clever hypermiler is probably not too much slower overall).
Remember this: Steering and brakes require a running engine, be very careful with turning the engine off while at speed.
I think the single most important thing is to have a steady flow in the driving, by avoiding full stops and also reduce the need for acceleration.
Of course, working the clutch will save fuel only if the slope is not so steep that your car can drive the engine without loosing speed (coasting).
_Power_ steering requires a running engine. I have never driven a car without power steering, but even I manage just fine once the speed increase beyond 5 kph or so.
The biggest issue is getting used to the mushy brakes. You have to push a bit harder before you notice the brakes having an effect.
A steady flow can be hard to maintain during rush hour. So my tip above is a bit specific (downhill during rush hour).
Remember that the things we write here are available for the public. One cannot be too cautious…
Its simple Swade. Pretend you are a glider pilot- you haven’t got a bl…y engine.
Oh and why tape over the gap between the front edge of the bonent and the grill and lamps – but watch out for overheating…
When you’re driving for a low fuel consumption you should accelerate quickly up to speed and then use the highest gear possible to keep the speed constant. Remember than an engine is most efficient when it’s run with a higher load (higher load = higher boost on the gauge). One method to increase the load even more is to accelerate, turn the engine off for a period and let the car slow down and then turn it on and accelerate again, but that would be dangerous on regular road and it’s doubtful you save that much if you drive in traffic.
A naturally aspirated engine is usually most efficient at some 70-90% of maximum load, a turbocharged gasoline engine has its peak at a slightly lower value (due to load enrichment to keep the engine cool). So don’t use full throttle for accelerations, but also don’t accelerate slowly. Try to keep the engine where it’s most efficient.
At higher engine speeds (1500-2000 rpm and higher) the engine will shut off fuel injection when coasting, so you never want to dip the clutch downhill, that will only increase fuel consumption and wear on clutch and engine. Try to use the brakes as little as possible and plan your driving ahead.
When driving you want to find your cars ideal speed. Higher speed means a higher power consumption but also a lower specific fuel consumption as the load on the engine increase. In other words, at a certain speed, probably in the range 60-90 km/h, your car will offer the best milage.
You should also use the recommended fuel, not more or less. Higher octane fuels than required do not contain more energy or offer improved milage, only increased cost. The engine and tranmission should use low friction oils and the tire pressure should be as high as possible. Preferbly relativly narrow low friction tires should be used. It’s also possible to reduce the aerodynamic drag by covering up part of the cooling air intake (you can for instance cover the grille with a plastic film) and using tape to cover all the gaps between hood, bumper, grill and headlights. Reducing the weight of the car is also useful, remove all att items you don’t need in the car (including excess washer fluid). You also want to use all power consuming devices as little as possible, that includes everthing from the AC compressor to the headlights. You do however want to use the ventilation fan in order to be able to keep the windows closed.
(I should stop hogging this thread, but I could not resist making another observation
)
This is not a problem! Swade will complete this race in the nude. He will not overheat any time soon.
Johan, even in fifth gear, the engine will cause the car to roll slower, no? I’m pretty sure my car rolls faster when I dip the clutch. And if you gently tap the throttle, you might be able to match the rotation speed so the clutch won’t wear.
Use up or empty your windshield washer fluid before the run. Water weighs ~8lbs/gallon, and an 2003+ 9-3 can easily swallow more than a gallon if low.
I’ve heard of people putting dry-ice around their fuel tank, which makes the fuel contract slightly, and by the time you finish, the fuel will be at normal temp and expand, allowing less fuel in at the end-of-run top-up. Personally I see this as cheating, so use this tip at your own discretion.
Wear shorts and a t-shirt and leave the shoes at home!
Wear a thong mate!
Am I the only one here impatiently awaiting pictures from Steven’s nudie-drive?
Hope he used sunscreen!
Oh God, did we forget to tell him to close the sunroof?
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