final drive ratios explained

Hence the manufacturers term it as the final drive ratio. The total drive ratio of a vehicle is the ratio between the engine angular velo.

Rear Axles Final Drive Automobile

Different transmissions have different ratios according to how the manufacturer expects them to be used.

. Since torque is what helps the vehicle accelerate a higher final drive ratio will offer better acceleration. The ratio of the speed of rotation of the powered gear of a gear train to that of the final or driven gear. The output shaft delivers 6002 1200 Nm and revolves by 666 23 2 333 13 rpm.

If you are trying to get the best fuel economy possible for your truck a lower ratio is a great way to do it. And by fitting a shorter final drive you can achieve better acceleration since you can increase the amount of torque to the wheels or you can fit a taller one and increase your top speed. The rolling radius of road wheels is 0366 m.

Worked example calculating the possible gear ratios for a vehicle. The final drive ratio is what you end up with when you factor in the transmission and transfer case gearing and the axle gear ratio. In this case the bicycles gears are both the transmission and the final drive ratio.

If you alter this ratio it also changes every gears effective ratio affecting the vehicles performance and economy. For example GMs popular 4L60e automatic transmission has a ratio of 306 in first 162 in second 10 in third and 70 in fourth. In other words for every single turn of the ring gear the pinion rotates 410 times.

Gear reduction is used for 1st through 4th gears in the transmission in the chart below. Since the final drive is the easiest and cheapest to change it it often used to change the behavior of a bike. Its the combination of trans gearing and FDR that effects acceleration not the FDR alone.

Gear Ratios can be difficult to understand but with a fairly brief explanation I will attempt to make this often misunderstood equation VERY easy to grasp. Its gear ratio is 21 and increases torque. The ratio is calculated by using the number of teeth on the pinion gear splined to the driveshaft yoke and the ring gear splined to the axle shaft.

A low ratio is a 373 and a high ratio is a 273 I know it seems contrary to what sounds correct but thats how it is. The gear set in the second illustration indicates overdrive. The rpm is 2806 at 105 kmh 65 mph the current tires are 29 inch the factory ratio is 373 and the new size upgraded tires.

High Final Drive Ratios. In fact the Ford F-150 which is considered the best-selling truck of all time offers trucks with a 3151 ratio at the lowest end of the spectrum. Rear end gear ratios or final drive ratio refers to the number of revolutions the drive shaft turns compared to one full revolution of rear wheels.

If we then divide the tire. Even though the Vette may only be a 273 the gearing in the transmission compensates for that. This ratio refers to the number of teeth on the ring ie driven gear divided by the number of teeth on the pinion ie the drive gear.

Therefore this implies that a ring gear with 41 teeth and a pinion with ten teeth results in 4101. Changing the final drive ratio heavily impacts the way the car behaves. The description tells you pretty well how to calculate it divide the number of engine revolutions required to make one full tire revolution into one.

Low range gear will also suffer as 1st gear low will now roll too fast as the tires are bigger this. The final drive ratio is typically the gear ratio for the differential or the final location where the gearing is altered before being sent to the wheels. The drive gear turns twice for every one revolution of the driven gear.

The reason a higher ratio will help accelerate a car faster is because the engine can spin up faster and creating more. If you increase the final drive ratio each gear will have greater wheel torque while sacrificing top speed. Answer 1 of 2.

Maximum engine torque is 1052 N m at 2100 revmm. The differential gear ratio on a stock standard 4x4 are made to suit the tire diameter which the vehicle is released with. A ratio of 3151 will give you a good mix of better mileage and decent power.

Using bigger diameter wheelstires with stock ratios will cause more wear and tear on clutch driveline and engine. Generic Final Drive Ratio graph. What is a final drive ratio.

The final ratio is the ratio between the front- and the rear-sprocket and is called final as it is last in line in the total gearing setup of engine to gearbox gearbox to front sprocket and front- to rear-sprocket. A higher final drive ratio will result in more torque at the wheels but a lower top speed. To turn the ring gear once the pinion would have to rotate 4 times.

Calculate the gear and final drive ratios for a vehicle from the given data. The final drive refers to the number of revolutions the engine crankshaft makes to get one full revolution of driven tires. Simply take the RPMs at the DRIVE pinion gear and divide them by the.

The final drive ratio of a differential unit of drive shaft is the ratio of the input angular velocity propeller shaft side to the unit to the output velocity of the unit drive axle and drive wheels side. The final-drive ratio is the extent to which the rotating speed of the driveshaft output from the gearbox finally reduces before it reaches the driven wheels. Notice the first gear ratio in the chart is 40271.

Maximum power is 373 kW at 4000 revmm giving a road speed of 130 kmh obtained from graphs and data. What does changing it doCar Gears - httpsyoutubebgGgH0j0KQESubscribe for new videos every Wednesday. A larger gear ratiosay 310correlates to shorter gearing while a low numberlike 270represents taller gearing.

If we have a 411 axle ratio a 30-tooth over a 22-tooth QC ratio being 13636 then our drive ratio DR is 56045. Heres the confusing part though. For example on a 40 ratio for ease of display there would be 10 teeth on the pinion gear and 40 on the ring gear.

How To Find Your Car S Gearbox And Final Drive Ratios And Efficiencies