Alright I always get this wrong. Example.. 3.55 = Slower out of hole, better top speed? 4.56 = Faster out of hole, not as good top speed? Or Opposite? Thanks guys or should I just say thanks yellowkota2k.... :beer:
Gearing?
01RTDurango
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Alright I always get this wrong. Example.. 3.55 = Slower out of hole, better top speed? 4.56 = Faster out of hole, not as good top speed? Or Opposite? Thanks guys or should I just say thanks yellowkota2k.... :beer:
Generally, that is correct. The low gearing (4.56 or lower) gives the mechanical advantage of providing more torque and getting the engine in its optimal powerband. Once you've upshifted, then the engine may not be in its optimal powerband. This is why it has a poor topend in comparison.
Higher gearing (3.55 or higher) makes the engine work MUCH more to get it going, but once it's moving it is a little easier and keeps the RPM's lower. You will also be able to get a higher top speed with a higher gear.
Just remember that torque moves mass, not horsepower. This is why you see turbo diesel trucks with 600 ft/lbs or torque and only 200 something hp. This is also why they can run very quick 1/4 times for being 6000+ lbs and poor aerodynamics.
Gearing has a few factors though. Weight, engine size, transmission ratios, and tire size are the main ones. This is why you will see many different factory gearing come from anything like a 3.08 to a 4.56 in trucks. Believe it or not, S-10's have that large of a gearing range from the factory.
Higher gearing (3.55 or higher) makes the engine work MUCH more to get it going, but once it's moving it is a little easier and keeps the RPM's lower. You will also be able to get a higher top speed with a higher gear.
Just remember that torque moves mass, not horsepower. This is why you see turbo diesel trucks with 600 ft/lbs or torque and only 200 something hp. This is also why they can run very quick 1/4 times for being 6000+ lbs and poor aerodynamics.
Gearing has a few factors though. Weight, engine size, transmission ratios, and tire size are the main ones. This is why you will see many different factory gearing come from anything like a 3.08 to a 4.56 in trucks. Believe it or not, S-10's have that large of a gearing range from the factory.
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Along and in conjunction to the point Josh made, auto transmissions are coming now (as you know) as 5-7 speeds. This is enabling the manufacturers to install higher gear ratio's in the tranny's making their cars/trucks quick as hell off the line and up to highway speeds, but allowing for longer/lower gear ratios in the diff's to cruise the highway's at 85 mph and at 1500 rpm's (Mercede's-Dodge-Chrysler is a big example for this...I have 3:08's in the R/T Charger)
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