I have a 2003 Subaru Forester with a 2.5 liter engine and a 5-speed manual. I usually shift when the engine speed reaches 2000 to 2200 RPM, except when I need the extra power for accelerating. I consistently get 38 to 39 mpg in the summer (34-35 in the winter) in combined city/highway driving. Engines get the best fuel economy when they run at least at 50% of max torque. In city driving at a steady speed, the engine speed has to be kept below 2000 RPM to keep the torque high. This will not hurt the engine, but helps my pocketbook.
It depends on how hard you’re accelerating really.
And this is something you can model an automatic for.
If you’re just lightly meandering your way up to cruising speed, especially if it’s a lower speed, then shifting early can be better. Keeping the RPMs lower gives you less leverage and power to accelerate with, but at the gain of fuel economy and reduced engine noise.
However, if some kind of situation comes up and you’ve got to gun the engine, hold the shifts out to the higher RPMs. It gets louder and fuel economy drops, but with the throttle farther open, you need the extra power.
And if and when you have to floor it, resist the urge to shift until you encounter the redline. A few hundred RPM before the redline is probably best. A four cylinder engine at full throttle isn’t going to experience full torque until somewhere in the 4K range, and full power only above 5K.
This is a case where you can drive an automatic and watch how it reacts to varying throttle application. Under light throttle, an automatic shifts low because there’s no need to run out the engine. But under harder throttle, the shifts are delayed. And if you floor it, the transmission automatically drops into the lowest gear available and holds shifts all the way to the red mark.
-Matt
I am sorry if you were offended. I replied in direct and polite manner, IMHO. I did not call anyone an idiot, ?snotty? or use any other pejorative terms. I did not imply that anyone was stupid by using terms like ?derr?. It is clear that I have had more snot blown my way in this thread than you have. I will resist the urge to escalate.
Note that this is information that I did not have, but you seem to think that I should have assumed, ?I was just referring to regular, around town [sic.] driving.? In addition, there was no information to indicate that either of you really know how to shift. I assume that many people do not use their transmissions well for a good reason. Many people, even some that have used them for years, don?t.
Since there was no indication of specific driving conditions, I had to assume that the RPMs given were for the full range of driving conditions, around town and interstate, twisty mountain roads and blue highways. I suggest that before you are tempted to get angry with someone on a forum for talking down to you, you consider the quality of your question and how it might have been formed better.
Let someone else drive your car for a ways and see what they do. Im supporting your husband on this one because you really only need to keep the RPM’s up if you are hauling a load of any sort. Higher RPM’s makes for more power and torque. If you are the type of person that drives like a maniac and likes to cut out in front of people while you are driving, then yes, keep driving the way you do. You can do it much easier than your husband if you arent lugging it.
To Litahni. I am a trained G.M. mechanic with also 200 hours of College Major in Electronics and minor in Mechanical Engineering! Lose the “RPM GAUGE”!(Tachometer). Put her in first gear, give her about a half throttle and then feel when she’s happy. Shift! Repeat until you obtain your desired cruising speed. If you need her to “hang out” like getting on the freeway choose your gear and put the petal to metal. Listen to the engine, when she’s happy shift! you will get a better “feel” by listening and feeling what the motor wants to do than you or your husband
your a pretty smart girl, since the car is just a 2.0 liter 4 cylinder, your methods sound about right, try shifting at about 2500, oh yeah and it wasnt your fault the last car blew up
here in england where 3 quarters of all cars are manual,or stick shift as you americans say!,we drive according to how the engine copes.for example,if you were going uphill in 3rd gear and shift up to 4th,say at 30mph,it would strain the engine because the revs are too low.you can shift as low as 2000 rpm,but usually when you are on a flat,or going down hill.i shift at approximately 2800rpm for normal driving,but dont forget the engine is designed to operate throughought its rev range with no damage!if you were to shift at 5000rpm,it would do no harm,except use more fuel!also the engine is at its most economical when it reaches maximum torque,which could be anywhere from 2000rpm,to 4000rpm ,depending on your engine.
You’ve hit on the real problem. Congratulations.
The next time you feel yourself becoming a skittish passenger, look over at him and imagine him driving naked. You’ll start laughing so hard you won’t be able to criticize!
I mean this in good humor, by the way. Please accept it that way.
Hi there Litahni i have drive Stick cars since i learn to drive in fact i learn to drive on a stick car/ actually i have over 10 years of experience driving stick cars and let me tell you there is no way that an auto car can match the level of pleasure that reving a stick car will give you , you have control of the amount of traction you like, the torque you like and when you want it in fact you can say that the perfomance on accelaration from a 1.6 liter engine with a stick will be significantly better than a 2.0 L engine with auto trans / auto transmission is for my just a lazy way to drive whoever going to your post. If you want to save some money on gas you can shift in a range of 2K - 3 K if the circustamces allow ( not on a hill or overdriving a car) however if you want to get the best perfomance of your engine usually you get at 4.5 K when you reach the max torque of the engine however take into consideration that you will get 30 - 40 % more miles per gallon if you stick to the 2- 3 k shifts and will not damage your engine if you make then at the right time and on the right circumstances.
hope it helps take care
MB how did this get bumped from august to now? litahni is probably in another zip code by now!?
The optimum gear shift point varies with throttle opening. The less you open the throttle, the lower the optimum shift rpm is. Also, the sky doesn’t fall if you shift at a somewhat higher or lower rpm, you just get less than optimal gas mileage. Running your engine at 2000 rpm when you are going 10 mph in a parking lot mostly wastes gas.
3,000 RPM’s won’t hurt the engine and 140,000 miles is a great time to get a new car. Your new one will probably go farther.
Does the turbo kick in below 3000 RPM? You might be missing a lot of fun. You can wind it up to at least the yellow limit on a regular basis before shifting. Excuse #63: “It blows the carbon out”. ;’) When you are cruising at constant RPMs you should be on the low end to save gasoline. I’m not familiar with your car, but I cruise at about 1700-2000 RPMs (55MPH-65MPH) in my Accord and get 28.5 MPG while commuting. EPA is 28 highway!
“Neither one of us can stand riding in the passenger’s seat.” Wow! Is that a loaded statement! 1.) Why would you want to “stand” in the passenger’s seat? (Heh.Heh.Heh.) 2.) You could both sit in the driver’s seat-----(No, Prof., don’t EVEN go there). Another series of Heh. Heh. Heh. All tongue-in-cheek, of course, just to lighten up this subject/forum a little.
Well I hate manual transmissions, I’ll never own one, but the shifting point depends, as has been noted, upon many things, like up hill or down, entering a freeway, passing, the load you are carrying, the condition of the road and several others. Excessive reving the engine shortens the life of the engine, what ever is excessive.