can you drive a car without a flywheel

[LeGideon]

No, you cannot drive a standard road-going car without a flywheel. The flywheel is a critical component bolted to the rear of the crankshaft, and its primary function is to store rotational energy, or inertia. This inertia is essential for smoothing out the engine's power pulses, allowing for stable idling and seamless gear changes in a manual transmission. Without it, the engine would likely stall as soon as you engaged the clutch or came to a stop.

In a manual transmission vehicle, the flywheel also provides the friction surface for the clutch disc to engage against. Removing it would make it impossible to disengage the engine from the transmission, meaning the car would lurch forward as soon as you started it. In an automatic transmission, a similar but often lighter component called a flexplate serves the same basic purpose of connecting the engine to the torque converter.

While some specialized racing engines, like those in top-fuel dragsters or certain formula cars, use extremely lightweight or non-traditional flywheels, these are engineered as complete systems with specific goals (like rapid acceleration) and are not practical or safe for daily driving. For any consumer vehicle, the absence of a flywheel would lead to catastrophic drivability issues and severe engine damage.

Engine Performance Aspect	With Flywheel	Without Flywheel
Engine Idle Stability	Smooth and consistent	Extremely rough, prone to stalling
Clutch Engagement (Manual)	Gradual and controllable	Impossible or violently jarring
Low-Speed Drivability	Manageable and smooth	Nearly impossible to control
Crankshaft Stress	Dampened and balanced	Excessive torsional vibration, risk of failure
Overall Vehicle Safety	Safe for road use	Unsafe and undrivable

[Henderson]

You'd get about ten feet before it stalled. That heavy metal disc is what keeps the engine spinning between the explosions in the cylinders. No flywheel means no inertia. The engine just jerks to a stop. Plus, in a manual car, the clutch has nothing to press against. You couldn't even get it into gear. It’s a non-starter for any normal car.

[EmeryRose]

Think of the flywheel as the engine's momentum keeper. It stores energy from each combustion stroke and releases it to carry the crankshaft through to the next one, creating a smooth rotation instead of a series of jerks. Without that smoothing effect, the engine would shake violently at idle and struggle to transfer power smoothly to the wheels. It's not just about moving; it's about controllable, safe operation, which simply wouldn't be possible.

[Meredith]

From a pure mechanics standpoint, attempting to run an engine without a flywheel is asking for immediate failure. The flywheel plays a key role in damping torsional vibration—the twisting forces that the firing pulses impart on the crankshaft. Without it, these vibrations would amplify, potentially leading to a cracked or broken crankshaft. It's a fundamental part of the rotating assembly, not an optional accessory. The risk of severe and expensive damage is extremely high.