BlackMax62

What the hell are they... I never understood what they mean. Can someone give me a rundown or give me a link so i can read up on that sheot. Thanks all.

Curious about my peice.
Black 98 5sp SE

Sarah99GXE

very good question...at least for me I was thinking about this myself & would like to understand a little more about it. I mean I can learn alot from this site but this is one subject that I have never seen discussed...

AntGVR4

I'm not sure this is right ..

Gear ratio..
you often hear this like 3.46, 3.0, 2.4, 1.3, .9
or sumtin like that .. meaning first gear, second gear, and so on..

what happens is the motor is always spinning at a certain rpm..and it connects to your tranny to a certain gear to spin the tires.. now..
the gear ratio is the ratio of revolutions at the motor : revolutions at the tranny ..
i.e. if it's a 3:1 ratio than for every 3 spins of the motor the tranny will revolve once..
now why are lower gears have higher ratio's than shorter gears ?
reason is when the car is at a stop you need a lot of power to get it going so you need a higher gear ratio.. but the problem is the higher the ratio is the car goes slower in that gear.. that's why it decreaes.. the last gear is usually 1:1 or 1:.9 so for every one revolution of the motor the tranny spins once..so you can go faster..

Try launching a car in 3-4 gear.. very difficult .. no power ratio is too low..
now try driving at 40 in 1st gear.. engine is revving to high..cuz the gear is short.. meaning it has a lot of power but it's not tall..

DO you get it kinda sorta ?

Ant

Sarah99GXE

Better than I did before thank you

NJ95gxe

good explanation Ant. Even I got it.

Now, to keep the gear thing going: What's the ideal RPM range per gear?

i.e. Where should my rpms be before changing from 1st. to 2nd? is it @ redline?

thanks!

kratz74

I assume you want best rpm range for acceleration. That being said most people on this board say to shift in the low 6000 rpm range. By the time you hit redline, your hP starts to dip. About gear ratios-you used to be able to buy cars and sepcify the gear ratios you wanted (lower for acceleration and higher for top speed). Even until recently the Mustang offered a choice of gear ratios for the GT 2.71 or 3.27. 3.27 gained about 1/2 second in the 0-60 and quarter mile but lost 1 mpg and maybe 5 mpg on top end.

AntGVR4

if you want to accelerate fast you shift right where your engine stop devolping power..
on the max it's around 6k rpm..

but for normal driving shift much much lower than that..
powerband for the max starts around 3K rpm.. so if you wanna race someone don't start under 3K cuz you won't be developing that much power..

You live in NJ ? .. I'm in clifton (northern NJ)
come by and i'll show you what rpm's to shift at

BTW: people might flame cuz my max isn't stick but i still know how to drive stick so shove it

Ant

Micah95GLE

I think that you should rev 400-500RPM past the power peak, so that when you shift, the engine won't fall too far out of the power band, and it will stay closer to the power peak.

Kato

Exactly. To get maximum acceleration take a look at a dyno chart. Basically, you're trying to maximize the area underneath the horsepower curve. This will give you the maximum amount of time at the highest hp your engine can put out. How do you do this? Find the peak hp and shift AFTER it sometime. This way, when your RPMs drop from the shift, the amount of hp the engine is still putting out is still higher than what it would be if you shifted at the peak. I believe Andi has formulas for calculating optimal shift points at his site Boostaholic.com. He also already has them calculated per his Max's dyno chart.