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Diesel to Gas


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Is it possible to change a Diesel engine over to a car Gas engine?  Would there be any advantage to doing that, like lasting a 1,000,000 miles.

Thank you for your answer.

3 Answers

If you mean swapping motors, yes but it isn't worth the work. If you mean physically reverse engineering the motor to run gas, no. And diesel engines last a LOT longer than gas motors. For max mileage, you want a diesel.

Thank you for your answer.

You're welcome


You mean modify a diesel engine to run on gas? No. It would be easier to start from scratch.

How they operate is too different.

Read up on "Otto cycle" versus "Diesel cycle"

Thank you for your reply.


The fundamental difference between the two is a diesel runs on compression-ignition, gasoline runs on spark-ignition. The diesel compresses the air in the cylinder so fast and to such a high pressure that fuel immediately catches fire when sprayed into the cylinder. A gasoline engine doesn't reach this degree of heat and pressure, a spark plug starts the flame. Gasoline will ignite in a diesel setup long before its supposed to and that will destroy the engine. It's basically engine knocking on steroids


There have been some engineering studies to see if a gasoline engine could be made to run like a normal 4-stroke/ diesel combination, omitting the spark plug and using compression alone, with the normal intake and exhaust strokes, but this has issues like normal diesels. It can't be cold, or you need a block heater and glow plugs, which pretty much offset the benefits of the compression-ignition concept. 

Add to that the fact that diesel's typically don't have throttles.
If you wanted a gas engine that lasted like a diesel, you would have to overbuild it, and there's just no market demand for that.

Diesels throttle their fuel input, not air if I remember right. I wouldn't say there's no demand. I feel like the government is set on getting rid of internal combustion engines and killing demand. I'd buy a gasoline engine that's as sturdy made as a diesel in a heartbeat. There's also the endless consumerism factor, people constantly buying brand new cars for the next "cool" feature and not caring about longevity of it. I'd say those are the two biggest killers for developing that kind of technology.

Diesels will modulate injector pulses.
I'm sure a handful of people would buy sturdy combustion engines. But it's not what the masses want.
Auto makers want sell as much as possible, for as cheaply as possible, and the government wants their fingers in everything.