Reply to thread

Message: <blockquote data-quote="Hellion94" data-source="post: 464103" data-attributes="member: 8471">This is true to a point. Let's say that there are 2 cars that make the same power. Let's assume that the power they make is enough to "top out" a set of 2.73 gears, meaning it can overcome the drag and everything associated with speed and get to the redline in 5th gear with 2.73's. Let's say the other car has 4.10'sThe car with the 2.73's will have significantly higher top speed than the car with the 4.10's, because the gear will run out far before the 2.73's do. However, if the hypothetical cars make less power, the 4.10's will be able to run the car to redline, and that may produce a higher top speed because it can utalize the entire RPM range in 5th gear. All the gear ratios refer to is the amount of rotation of the axle in comparison to the driveshaft. A set of 4.10 gears will turn the driveshaft 4.10 times for every 1 rotation of the tire, whereas a set of 2.73 gears will only tun it 2.73 times. Let's say that the driveshaft RPM is 5,000 with 2.73 gears, the tire will be turning 1,831.5 times in a minute, whereas with 4.10's the tire will turn 1,219.5 times. If we factor that out for Tire circumference, that means for a 100" circumference tire, the 2.73 gears will travel 15,262.5 feet per minute at a driveshaft speed of 5,000RPM. the 4.10's will only travel 10,162.5 feet, or almost a mile less in a minute, which means at 5,000 RPM driveshaft speed, there could be almost a 60mph difference between the two. It should be stated that a 100" circumference tire is HUGE, as a 28" tall tire has a circumference of about 88", but it was just used to try and simplify the math, and should have no bearing on the distance covered.</blockquote>