Fast or slow acceleration for best MPG

I have been thinking about this for a little bit and maybe someone with more brain power can straighten me out.

60 mph is the goal, if you floor it you obviously get there quicker and are at your cruising speed faster. If you slowly accelerate it will take longer.

Which uses less fuel to get to 60mph?

 

I'm no scientist, but gonna go out on a limb and say slow and steady.

 

I'd think slow acceleration up to speed.

 

Always heard staying under a certain rpm, but I don't know the sweet spot.

 

I actually played with this on Sunday. I get better MPGs going slow and steady, as judged by the onboard computer. I drove slow and steady to my destination. then punched it on the way back. It was an 11 mile trip, fairly flat both ways, and spent about the same amount of time at red lights. To: 13.5 MPG, back: 11.6 MPG

 

The issue with slow is your accelerating for a longer time.

I guess I will have to test it out.

 

There used to be TV adds saying, "don't be fuelish" in which they promoted slower acceleration.

 

I find keeping it around 2k rpms is the sweet spot on my 18 5.7

 

I have had the same question and have been playing with it a little bit every morning driving to work. In general the slow and steady wins, but there are some instances, like going downhill on an interstate on-ramp where I think gunning it quick and then let it free/coast while you merge and get it set at your highway speed, you are actually better off than slowly increasing speed over a long distance.'
However, slow and steady wins most of the time.

 

Not to jack this thread, but I wonder the same on braking . . . pump the brakes over a distance to slow down as I get to an intersection or just brake harder once and for all? I usually do the former.

 

As long as you are not laying on the gas until close to the intersection and then hitting the brakes hard, it should not make a difference. Assuming you let go of the gas pedal at the same point, just coasting at idle to close to the intersection and then hitting the brakes hard, or coasting while lightly braking over the same distance should not make a difference.

 

That's what I thought too. And yeas, I do all of the things you noted.

 

What does make a huge difference is avoiding sitting idle at a red light. I time the lights for as far as I can see ahead. If I see I can make it through, even gunning it a little, I will be better off than sitting at a light idling for a minute or two. If I see well in advance that I will not make it, I start letting off the gas and slowly coasting to the intersection to minimize the time that I sit there burning gas.

 

I have a 15 mile commute - 8 miles city/ 7 miles highway. If I drive careless and just enjoying the V8 power, I get 14 MPG; if I use some of the 'tricks' mentioned above, I get 17 or sometimes 18 MPG on the same route, same time of day.

 

I think the lower the RPM the better the MPG.

 

Thanks for the help boys. I guess I will lay off the skinny a little

 

Don't listen to their nonsense. Flooring it will give you the best gas mileage because you'll get to speed faster. They know this, but don't want you to know. It's a well-guarded secret.

 

Technically, the engine has the least pumping losses at WOT, is most efficient at max torque(RPM). So if you WOT and let off around 3500rpm rinse and repeat until you hit 60mph that is your best possible mpg. Problem is the Tundra is geared so low, 3500rpm is alot faster then you think and because it's an auto, once you let off the gas it will shift into too high a gear. Best done with a manual transmission.
The way a Tundra is set up, slow and roll will yield the best mpg

 

I agree. If you consider modern freight trains, they have diesel engines that run at WOT which power the electric motors that actually move the train. They do this because the engine is most efficient at WOT.

 

What is "WOT"?

 

Wide Open Throttle

 

Thanks. Learn something new everyday.

 

I've always thought that the laws of physics apply to my truck. The amount of force required to accelerate the mass of the truck will need to be increased in order to increase the rate of acceleration. The engine provides the force by burning fuel and more fuel is needed to provide more force.

 

Us older farts remember a PSA commercial from the 70's gas embargo where they used an egg on the gas pedal, and emphasized no jack rabbit take offs. Me personally, I put my foot thru to the engine, AND let it RIP

 

You are not flying a jet. Slow and steady will be better. I say that because years ago they figured out that the quicker jets get to cruising altitude the less fuel they burn. People started to complain about the steep take offs.