Hi guys, i have a question about the gears on our cars. Why is it that in the first gear we can accelerate from 0 to 40mph in like 2 secs and we feel the car pulling really hard, but when we get to the second or third or fourth gear, the car doesn't pull as hard and each gear does not give a 40mile window on the speedometer. it is like the hp decreases with each upshift. What is the logic behind that anyways? can we do something to make all gears perform like the first? THanks guys.

 

Do you have an understanding of gear ratios and what they do?

 

that's funny... just the other day I was thinking 2nd and 3rd pull like a *****.

Think of it this way... 1st gets you "going", 2nd - 4th get you "there". 6th gets you gas mileage but isn't very fun. 5th... come to think of it, I don't really use 5th very often.

 

I'll play the dumb one here cuz i don't know what gear ratios do.

 

translate the revolutions of the engine into differing numbers of revolutions at the drive shaft...that is the 'ratio': the number of shaft revolutions compared to actual engine revolutions...in first gear the ratio favors 'getting started', as the transmission (manual or auto) moves up the gears, it becomes more and more a matter of a 1:1 relationship (and overdrive gears actually invert the relationship)...

this is of course totally independent of the actual axel (differential) drive ratio...

you can also refer to some other sources...

http://www.geocities.com/dave240z/trans_ratios.htm

 

Howstuffworks "How Gear Ratios Work"

 

Thanks jjs.

 

the reason lower gears pull harder is because of the ratios and a thing called torque multiplication, let's say first gear is 4:1 and you have 250ft-lbs of torque and 250hp. in 1st gear because of the gear ratios you have 1000ft-lbs of tq to the ground but only 1/4 of the hp you have to the ground. in a gear like 4th which is 1:1 you have 250ft-lbs of torque and 250hp to the wheels.

understnad?? if not i'll go into more detail and get an article on it.