What is the best gear ratio for speed?
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.
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What is a 40/1 gear ratio?

In a worm gear, a threaded shaft engages the teeth on a gear. Each time the shaft spins one revolution, the gear moves one tooth forward. If the gear has 40 teeth, you have a 40:1 gear ratio in a very small package, such as in a windshield wiper. A mechanical odometer is another place that uses a lot of worm gears.
How do you find the lower unit gear ratio?
To calculate the gear ratio:
Divide the number of driven gear teeth by the number of drive gear teeth. In our example, it’s 28/21 or 4 : 3. This gear ratio shows that the smaller driver gear must turn 1,3 times to get the larger driven gear to make one complete turn.
What is outboard gear ratio?

‘Gear ratio’ refers to the number of drive shaft revolutions for one revolution of the propeller. So if an engine has a 2:1 gear ratio, it means that for one revolution of the propeller the engine drive shaft turns twice. We can find the propeller shaft RPM by dividing the engine drive shaft RPM by the gear ratio.
What gear is 70 mph?
You’ll use 5th or 6th gear for highway cruising at speeds of 60 mph to 70 mph and are ideal gears for best fuel economy.
Does higher gear ratio mean faster?
Gear ratios can be boiled down to a single statement: Higher ratios (with a lower numerical value) give better torque/acceleration and lower ratios allow for higher top speeds and better fuel economy. Higher ratios mean the engine has to run faster to achieve a given speed.
What gear ratio is better for torque?
With a 4.30 ratio, it turns 4 1/3rd times for every revolution of the rear wheel. The numerically higher gear ratio (in this case, 4.30) increases wheel torque and improves acceleration from low speeds.
What is a 5 to 1 gear ratio?
The driving gear has fewer teeth than the driven gear. For example, if a motor drives a 12T gear to a driven 60T gear on an arm, the 12T driving gear has to rotate 5 times to rotate the 60T driven gear once. This is known as a 5:1 ratio.
How do I determine my axle ratio?
Divide the number of the ring gear’s teeth by the number of the pinion’s teeth. This will give you the axle ratio.
How do I find gear ratio of my boat?
Stop your vessel in a safe area and, using your calculator, multiply the speed by 1,056 (the Constant for Unit Conversion). Divide this result by the pitch of your propeller. Record this First Result. If your speed at 2,000 RPM was 10 knots, then: 10 x 1,056 = 10,560.
Do outboard motors have gear reduction?
The propeller rotates at the same speed with the propeller shaft, while the propeller shaft usually rotates much slower than the engine crankshaft turns, at the same throttle setting. This is due to the reduction gear which exists on all the outboard engines among their crankshaft and propeller shaft.
How fast can you go in 1st gear?
Remember each car will be geared slightly differently, but a good rule of thumb for changing gears is that first gear is for speeds up to 10 mph, second gear is for speeds up to 15 mph, third gear is for speeds up to 35 mph, fourth gear is for speeds up to 55 mph, fifth gear is for speeds up to 65 mph, and sixth gear …
How fast can you go in 2nd gear?
The maximum recommended speed in 2nd gear is: 69 mph (110 km/h). This position is to be used when stronger engine braking is needed.
Does gear ratio affect horsepower?
A higher numeric axle ratio (4.11:1) keeps the engine running in the higher horsepower range, thus improving performance.
What happens when you change gear ratio?
Modifying the axles’ gear ratios changes the amount of revolutions of the driveshaft per each revolution of the wheel. Going to lower gears (ironically, a numerically bigger ratio) will increase the rpms of an engine (taking for granted the same diameter tire and going the same speed).
Is it better to have a higher or lower gear ratio?
A gearing ratio lower than 25% is typically considered low-risk by both investors and lenders. A gearing ratio between 25% and 50% is typically considered optimal or normal for well-established companies.
What is a 5.2 1 gear ratio good for?
The low gear ratios like 5.2:1 and 5.3:1 are great for fishing baits that pull hard like deep crankbaits, big swimbaits, and deep water spinnerbaits. The low gear ratio helps you reel the bait slower, keeping it in the strike zone longer when fishing moving baits in the deep water.
Does a smaller gear turn faster?
In a small/large gear set-up, when the small gear has made a full rotation, the large gear will not have yet completed a full rotation. Thus, the smaller gear makes more revolutions in a given time, rotating at a faster pace than the larger gear.
Are 3.73 or 4.10 gears better?
4.10s are going to accelerate faster and decelerate faster on lift. However the trade off is greater fuel consumption per mile driven and higher engine speed per given road speed. In basic terms the 4.10s will feel quicker and 3.73 will feel faster.
Which axle ratio is best?
For the Best Towing Capacity:
If you are planning on towing large payloads and have a V8 gas or diesel engine, an axle ratio between 3.55 and 3.73 will be perfect.
How do you measure the speed of a boat?
The speed of a boat having an engine to deliver P horsepower and displacing D pounds is written as: S = Speed = sqrt(P / D) * C , where S is the boat speed and C is the Crouch constant. The above equation is known as Crouch’s formula.
How is prop slip calculated?
Formula for Calculating Prop Slip
Theoretical Speed = (Revolutions Per Minute ÷ Gear Ratio) × (Pitch ÷ 1056) Prop Efficiency = (Actual Speed ÷ Theoretical Speed) Percentage of Prop Slip = (100% – Prop Efficiency)
Do cavitation plates work?
They help prevent against “blow out” when taking off shallow. Plates with wings can help boats track better when running. Different boats will see varying improvements depending on the type of boat. Tunnel hull boats usually see the most dramatic performance increase from cavitation plates.
Can you put an outboard motor in gear out of water?
There is no difference putting the motor in gear at idle in or out of the water. The prop shaft will actually spin the prop with less initial resistance than if the prop was in the water.
How fast can you go on 2nd gear?
It’s possible to reach speeds of up to 90 mph in 2nd gear, but it’s not advisable. If you’re driving with your RPM in the redline for an extended period, the engine can blow. Driving at high speeds in 2nd gear regularly also increases wear and tear on the engine.