Is it bad to drive a 6mt in high gear in the town, say 5th gear cruising at 30mph, gives you about 1.5 1.6rpm? And would it be bad to push the gas pedal to half throttle, even though you will have slow acceleration in 5th gear?

Go Bears.

 

No / no.

Note that I'm assuming that you don't always stay at really low rpms.

 

Why would it be bad?

Wait, are there any instances where it would be bad?

I don't drive manual so I'm not sure.

 

not bad for the car, but could be potentially dangerous if you need to accelerate quickly. it's usually better to stay in the optimal gear, no matter the speed.

 

You just don't want to lug the engine.

Getting into 5th gear @ 30mph strikes me as going a bit overboard... why be in such a hurry to upshift? If you have to accelerate quickly, you'll have to downshift. If you just mash it at that speed/gear combination, you'll probably lug the engine.

I don't get it. Are you just trying to improve your mileage?

 

iv never done it so idk

 

I don't know what 'lug the engine' means, is that a term for when the car kinda shakes a little while trying to accelerate in a high gear?

and yeah, main reason would be for increased mileage, or being distracted like on cell phone, changing radio station etc..

 

you could foul your spark plugs...

 

Yes. That is exactly what lugging your engine means. While not dangerous per se, when you try to accelerate from very low RPMs in a high gear that is when your car is most susceptible to detonation. If you are doing that and you hear any pinging noises coming from the engine, switch to a lower gear to put less wear and stress on your engine.

Note that driving your car at low RPMs doesn't necessarily save gas. Yes, steady state cruising at 65 mph w/ 2500 rpm will save more gas compared to 80 mph at 3000 rpm, but when you are actually accelerating, your car is most fuel efficient at moderate throttle.

The thing that causes the greatest waste of gas is accelerating when unnecessary. If you want to maximize gas mileage, try to do things like rolling up to a red light or stop sign w/o accelerating up to it. Let your car's natural momentum carry you to where you want to stop. You've seen people who are constantly either on the accelerator or on the brakes. This is the sure fire way to really bad gas mileage and premature wear on your brakes.

 

If you are in a low gear and press pedal half way you are going to burn more gas than if you have it in 3/4 gear. I try to not have it lower than 2300 RPM. The way I look at it I want to always have some pull incase of emergency and need some power right away. Also, if you are at like 4000 RPM you are BARELY if even at all burning more gas if you aren't excelerating. Pedal depression is a better gas of the gas you are burning, not so much RPM's. I think a member mentioned as well it can cause spark plugs to go out quicker/need cleaning sooner.

Hope this helps...

 

Cool, thanks guys. I'll have to get that mentality of having it at 2.5k rpms isn't using that much more gas, it will be hard though.

Also, its nice to see a thread with a question, and some dignified answers, rather than constant bickering and fighting.

 

I agree with KulG35 that acclerator pedal pressure determines mileage much more than RPMs. In fact, if you push the "info" tab and then "enter" you'll see that MPG graph move as you accelerate, giving a fairly precise idea how much pedal pressure affects mileage. Keep your foot light on the accelerator for better mileage.

Don't lug this engine. The VQ performs most efficiently at relatively high RPMs. That's why the redline is at 7500, higher than most other sport sedans.

Also bear in mind that the accelerator pedal is hinged at the top, not the bottom, so your foot needs to be toward the top the pedal to avoid the hesitation and lurch response many complain about with the G35.

 

why do you burn more gas at the same rpm in different gears? 1st gear at 3000 compared to 6th gear at 3000? the MPG guage barely says 10 MPG in 1st at 3k when going 3k in 6th i get above 20?

 

You don't burn more gas per unit of time, but you do burn more gas per mile. Once you're up to speed, it takes minimal effort for the car to stay at that speed. Assuming the effort of the engine is approximately the same, given the same RPM in different gears, then you'll be burning about the same amount of gas per minute.....the trick is that you're going faster while doing it, so miles per gallon increases.

 

Your better off being in a lower gear around town. 3rd or fourth max.
If these cars had gobs of torque like a V8, it wouldn't matter. The car would always be responsive. But you actually put a load on the engine when you try to accelerate at slow speeds in a higher gear.

Use the gear that is designed for that mph/rpm range.