Diesel in a high compression gas motor?

[BluEyes1981]

Well, I searched and only found info about gasoline in a diesel cycle motor. I'm wondering how diesel fuel would work in a high compression gasoline motor.

My thinking is that the reason we don't have 14:1 compression gasoline engines running on the street is because pump gasoline cannot resist preignition at the higher compression ratio. Well, we all know that diesel has a higher flash point than gasoline and takes roughly 20:1 to ignite on contact. So, possibly high compression (for a gas engine) plus a spark will get the job done?

Has anyone tried this? Anyone got a used hi-comp circle track motor laying around that they would be willing to try this on? (with an unrestricted carb of course) Comments welcome.

[72chevelleOhio]

The most popular diesel compression ratios are around 17 and 18 to 1.
Allowing fuel to be dumped into the intake of a diesel is a great way to make it scatter. If you want to stand there and watch you could catch a rod or piston in the face.
Diesel gets injected directly into the cylinder not into the intake tract like a gas engine. The start of injection is also ignition timing.
GM already had a 350 to diesel engine conversion, it was junk!
I highly recommend not trying this, especially if your trying to use a carb to put fuel into the engine.

[KiwiBacon]

As already mentioned, injection timing is critical in a diesel engine. Fuel into the intake is a dumb idea, yes propane injection fits this category.

[curtis73]

Yep. If you tried to compress diesel to 14:1, it would self ignite before you wanted it to. The whole point with diesel is that you compress the air which heats it, then inject the fuel directly into the cylinder and it self-ignites.

If you're thinking about burning diesel in a spark-ignition engine, it won't work. The spark isn't enough to ignite diesel. the other issue is getting diesel to atomize. It requires super high pressure (over 30,000 psi in some diesels) through very sophisticated injectors to get it to atomize. If you tried making an injector spray it into the intake it would almost instantly return to a liquid puddle.

I like how you think, though. Its a fine idea, just that diesel is so hard to get burning without a lot of help.