What is the speed ratio between the engine and the tires?

[LeahMarie]

The engine speed is transmitted to the drive wheels at a 1:1 ratio, the vehicle speed would be too fast with very little torque, making it impossible to drive on the road. The main reduction ratio i is approximately (i=7-8). Engine speed ratio: Idle speed is between 750-950 rpm. For manual transmission city driving, it is generally controlled between 1500-2000 rpm. The engine speed ranges from 1000 to 3500 rpm, with maximum torque output around 3000 rpm, after which it becomes inversely proportional to the speed. The engine speed can be monitored via the tachometer on the vehicle dashboard. Normal driving usually stays below 2000 rpm, depending on the specific vehicle model. Tire speed ratio: Tire specifications include markings such as 205/55R1691V, where "V" represents the tire speed rating.

[VanFelicity]

I've repaired countless cars, and the ratio between engine and tire rotation speed is quite complex, primarily determined by the transmission gear and vehicle design. The ratio isn't fixed – in my experience, it's higher in first gear where the engine might rotate three to four times for every tire rotation, while in high gears like fifth, it approaches a 1:1 ratio with nearly synchronized rotation. Factors influencing this include the transmission gear ratio size, differential settings, and tire diameter. For instance, larger tires slightly reduce the rotation speed ratio. This ratio directly affects the vehicle's power performance: high ratios provide quicker acceleration but consume more fuel, while low ratios offer fuel efficiency and smoothness during cruising. In practical driving, manual transmission cars allow drivers to distinctly feel ratio changes through gear shifts, helping avoid engine lugging. To understand your car's specifics, consult the manual or observe the tachometer during a test drive.

[McJoanna]

As a car modification enthusiast, I study this gear ratio every day, which determines the core of a car's explosive power. A lower gear with a higher ratio like 4:1 means the engine turns more times to rotate the tires slower, resulting in a fierce start. Higher gears like 1.1:1 are almost direct drive, maximizing speed and fuel efficiency. Modern cars with CVT continuously vary the ratio, which is very smart. Tire modifications can also affect the ratio – for example, wider tires may require slight ratio adjustments, impacting acceleration efficiency. I've personally tested different ratios on the track and experienced how lower ratios provide stable output in high-speed corners. I advise fellow car enthusiasts to pay attention to ratio changes, as they can optimize handling and fuel consumption – don't just focus on horsepower numbers.

[Elijah]

Having driven for ten years, I find the engine-to-tire rotation ratio quite practical. The ratio changes with gears—higher in first gear where the engine turns more while the tires rotate slower, and almost 1:1 in higher gears. Automatic transmission cars adjust this ratio automatically via the computer, requiring no manual input. Understanding it aids in driving, such as using lower gears on uphill climbs to maintain a higher ratio, providing sufficient torque for safe ascents; on flat roads, a higher ratio saves fuel by avoiding wasteful high RPMs. Tire size also alters the ratio—larger tires result in slightly slower speed at the same RPM. As an experienced driver, I regularly check my vehicle to ensure the ratio matches road conditions.

[Adams]

Thinking back to the era of old cars, the gear ratios were simple and direct, with the engine turning three times before the tires moved once. Nowadays, vehicles have improved, with optimized and more flexible ratios. For example, my new automatic car automatically balances the ratio when I step on the accelerator. Gear ratios affect acceleration smoothness and fuel consumption control. Too low a ratio results in slow crawling and high fuel consumption, while too high a ratio can lead to loss of control. The ratio may drift after tire aging or modifications, requiring regular checks. I've found that a well-balanced ratio can extend engine life, so I recommend paying attention to the manual guidelines.