Question about the use of overdrive........

I was under the impression that if you wanted an extra burst of speed, you down shift into a lower gear that gives you higher RPMs but much more power. I'll agree that overdrive is generally for long-distance highway driving. It is a higher gear - the RPMs are lower and so is the power, but it takes less power to keep your car steady at highway speeds and it ends up saving you gas.

I'm having a hard time trying to explain it in common terms. My father's a diesel mechanic and my fiance is an auto mechanic, too. I've been driving a 5-speed Mazda Miata for almost 7 years. (And I love it!)

you've confused me now Vera??????

How did I confuse you? Do you understand how the gears work? Overdrive is just one more gear up. You wouldn't want to drive down the road at 6000 RPMs. You'd waste a lot of gas. When you keep shifting up, you make the RPMs go down. (RPMs = Rotations Per Minute). My Miata gets the best power at 6000-7000 RPM, but driving around like that all the time is a bad idea.

The engine's rotations per minute.. every time the engine parts rotate, all the cylinders fire once per 360 degree rotation. Every time they fire, they use GAS. The more times they fire within a minute, the more GAS gets used. Got it now?

you tell him Vera

my bad, thought it was revolutions.

Quote:

Originally posted by VeraLynn

Overdrive is just one more gear up. You wouldn't want to drive down the road at 6000 RPMs. You'd waste a lot of gas. When you keep shifting up, you make the RPMs go down.

Do you drive with 2. gear in the motorway? Usually driving with 5. gear 120km/h my RPM's are ~3000. And that's the optimal for engine to work smooth.

But I don't have lots of experience about automatic transmissions. I love manual.

Overdrive can refer to two different things. An overdrive is a device which was commonly used on rear-wheel drive automobiles to allow the choice of an extra-high overall gear ratio for high speed cruising, thus saving fuel, at the cost of less torque.It also refers to a combination of gearing inside a transmission or transaxle which results in the output speed being greater than the input speed. In the latter case, "overdrive" does not refer to a physically separate identifiable part/assembly.The overdrive consists of an electrically or hydraulically operated epicyclic gear train bolted behind the transmission unit. It can either couple the input driveshaft directly to the output shaft (or propeller shaft) (1:1), or increase the output speed so that it turns faster than the input shaft (1:1 + n). Thus the output shaft may be "overdriven" relative to the input shaft. It is actuated by a knob or button, often incorporated into the gearshift knob, and does not require operation of the clutch.
And i love manual also

@ ascaris - see what i mean?

my answer was clearer, shorter, and easy to understand.

just use overdrive like a 5th gear for an automatic, no need to go into more
information, if the guy has to ask this...he dont know about RPM's, gears or
anything else related to this

So i guess my post is useless

Quote:

Originally posted by veltiwths

Overdrive can refer to two different things. An overdrive is a device which was commonly used on rear-wheel drive automobiles to allow the choice of an extra-high overall gear ratio for high speed cruising, thus saving fuel, at the cost of less torque.It also refers to a combination of gearing inside a transmission or transaxle which results in the output speed being greater than the input speed. In the latter case, "overdrive" does not refer to a physically separate identifiable part/assembly.The overdrive consists of an electrically or hydraulically operated epicyclic gear train bolted behind the transmission unit. It can either couple the input driveshaft directly to the output shaft (or propeller shaft) (1:1), or increase the output speed so that it turns faster than the input shaft (1:1 + n). Thus the output shaft may be "overdriven" relative to the input shaft. It is actuated by a knob or button, often incorporated into the gearshift knob, and does not require operation of the clutch.
And i love manual also

I was trying to explain THAT without all the technical jargon. *I* understood you, but was trying to keep it to layman's terms.

Quote:

Originally posted by Latino

@ ascaris - see what i mean?

I see your point mate.

i thought my post was pretty ez to understand.

Quote:

Originally posted by DirtFloorPoor

i thought my post was pretty ez to understand.

it was, you said Vera confused you, we got it

@ ascaris -

Quote:

Originally posted by DirtFloorPoor

i thought my post was pretty ez to understand.

it was...but it didnt look like jeff got it, he still wanted to check his manual and ask techs etc..
obviously it was easy for alot of the rest of us..

even a female made the answer more technical than it should have been

Quote:

Originally posted by bisthrngrl

[reply=DirtFloorPoor]
i thought my post was pretty ez to understand.

it was, you said Vera confused you, we got it
[/reply]


I confuse a lot of people.

w00t!!

a 4 page thread in the car section and it doesnt even have car pics!

yay!

Quote:

Originally posted by Latino

w00t!!

a 4 page thread in the car section and it doesnt even have car pics!

yay!

I think watty is pouring the cognac already.

ahhh, your trick Vera, cute and confusing, now i got you figured out

Here's your car pic...