The conventional procedure for selecting gear ratios is to pick ratios that run the engine rpm to redline at the end of the medium and longest straights, and pick the lower gear ratios to minimize the rev drop at each shift. This method minimizes the number of shifts per lap.
What gear ratio is best for speed?
4.10:1 gears
In the real world, typical street machines with aspirations for good dragstrip performance generally run quickest with 4.10:1 gears. Lower gears are required if the car is very heavy, or if the engine makes its power at the upper end of the rpm scale.
How do I choose a diff ratio?
To find the ideal selection, multiply the final drive ratio by the redline speed in fourth gear (152 mph) and divide that by the top track speed (140 mph). This would yield a theoretical 3.33—which is close enough to the nearest available final drive ratio of 3.36:1.
How do I know my rear gear ratio?
Turn the wheel TWO revolutions and count the number of driveshaft turns. The number of driveshaft rotations will help you determine your rear axle ratio. For example, if it turned 3 and a half times, it’s a 3.50:1 ratio. If it turned 4 and a quarter times, it’s a 4.25:1 ratio.
How can I tell what gear ratio I have without pulling cover?
So an easy way to determine your actual gear ratio is to check the tag attached to the differential cover by the cover bolts. On the tag there should be some numbering such as 3.54 or 3.73, either of those numbers will give you the stock axle ratio.
Which rear end gear ratio is best?
The most popular rear-end ratio in trucks today is the 3:55, which sort of averages towing power and fuel economy. This is a good ratio for the occasional towing or hauling individual. For a person who tows more often, and heavier loads, the 3:73 or 4:10 may be more appropriate.
What are 3.73 gears good for?
Is 3.73 a good gear ratio? FACT: A 3.73 axle ratio is ideal for towing heavy loads on flat terrain and will produce increased fuel economy during steady-state, long-distance highway driving.
What are 3.55 gears good for?
With a 3.55 being a higher numerical number, Garrison says it will put more torque to the tire, allowing for faster acceleration and better performance on hill climbs. However, the tradeoff is burning more fuel through a higher engine speed.
How do I know what rear end I have?
To figure out exactly what axle you have, you can look for the Dana stamped bill of materials number. This stamped number can usually be found on the righthand side or on the longer axletube on the same side of the tube as the differential cover, facing the rear of the truck.
How do I know my axle gear ratio?
Method 1: Count the number of teeth on the ring gear and the pinion. Divide the number of the ring gear’s teeth by the number of the pinion’s teeth. This will give you the axle ratio.
What gear ratio is a Dana 35?
The Dana/Spicer Model 35 is an automotive axle manufactured by Dana Holding Corporation since 1985 when American Motors (AMC) sold its axle tooling equipment to Dana. The axle was originally named an AMC-15 when it was first made in 1962.
Available Gear Ratios.
| Ratio:1 | Pinion:Ring Teeth |
|---|---|
| 3.31 | 13:43 |
| 3.54 | 13:46 |
| 3.58 | 12:43 |
What rear end do I have by VIN?
Identify the VDS section, the fourth through eighth digits of the VIN. This section typically includes information such as the vehicle model, engine size and body type. While not every vehicle manufacturer includes gearbox ratio information in the VDS, this will be where the information is found if it was included.
Is a 3.92 rear axle ratio good?
But opt for the higher 3.92 axle ratio and that same truck packs a higher towing capacity of 9,930 pounds. The extra towing capacity comes about because the increased engine spinning helps improve off-the-line acceleration and pulling power when carrying heavy loads.
What is a good gear ratio for a street car?
If it’s a daily driver, chances are you’ll want to keep your gear ratio at 3.23 or below for optimal performance and lower cruising RPMs. For street and strip applications, a popular choice ranges between 3.42s and 3.90s, giving you that extra oomph on the track while maintaining a tolerable cruising RPM on the street.
Can you change axle ratio?
To counteract the effects of larger tires, you can change the gears in your differential(s) to increase the ratio of how many revolutions of the driveshaft it takes to make one full revolution of the wheel (raising the engine rpm at the same speed).
Are 3.55 or 3.73 gears better?
3.55 gears will give you better gas mileage while 3.73 gears give you better acceleration and performance. The numbers you are using are common Final Drive Axle Ratios for vehicles, so the question will be answered in that context.
What are 410 gears good for?
This equates to a greater amount of power transferred to the wheels. Installing 4.10 gears improves the car’s performance on the track but with negligible effects to the highway driving. If your car is equipped with an overdrive, you may not even notice a difference in gas mileage with the new higher gearing.
What is the difference between a 3.73 and 4.10 axle?
3.73, for every 373 rotations of the driveshaft you get 100 rotations of the axle, and for 4.10, for every 410 rotations of the driveshaft you get 100 rotations of the axle. Now, this means that your engine is spinning faster on 4.10 rather than 3.73.
Is 3.31 or 3.55 axle ratio better?
Normally, the 3.31 would get you better gas mileage, on highway. But, with the 3.55 you will get a bit more pulling power so less time at higher RPM to get your trailer moving and when going uphill. If most of your towing is flat highway, the 3.31 should do you fine.
What’s the difference between 3.15 and 3.55 gears?
The 3.55 will make the gears seem shorter meaning you will shift more often. The trade off is faster acceleration for less gas mileage with the 3.55’s and vise versa with the 3.15’s.
What is the difference between 3.55 and 3.92 gears?
3.92 is about 10% lower than the 3.55 with the same size tire. With the same rearend ratio the standard 17″ wheels and tires are effectively about 6% lower geared than the 20″. So you can get about halfway between the two ratios depending upon what you choose for wheel and tire size.
Contents