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Does a engine really need compression to run with todays injected engines once started!?
I build low compression carb-ed racing engines that win by using less drag of compression to make horses! More timing is needed at the cam, burn stroke and ign. but seems to get the job done on todays pump gas! A low reversion high timing engine that uses the explosion to build compression with the fuel burn timing more correct for the power stroke! If a shorter stroke can be used it would need less fuel and produce more power!
9 Answers
- 7 years ago
Without at least *some* compression, there wouldn't be enough air (oxygen) in the combustion chamber to generate enough power to overcome internal friction and keep the crankshaft spinning.
If you think about it, even a "low compression" engine of 8 or 10 to 1 takes a volume of air and compresses it to 1/8 or 1/10 it's original volume. The fuel injection system is designed and calibrated to inject the right amount of fuel to give a burnable mixture with that amount of air.
With no compression, the fuel injection system will be making the mixture MUCH too rich - it may not even be able to ignite and would certainly "run" with a lot of black smoke and soot - if it could run at all.
Another factor is that an engine with no compression would have to have no rings (or really, REALLY bad ones) and/or intake or exhaust vales that don;t seal. If this were the case, there would be no way to contain the pressure of combustion and harness it to drive the piston down.
So - no - no compression equals no running!
Source(s): past journeyman auto mechanic (practice) Years of vocational & automotive education (theory) - Country BoyLv 77 years ago
Must be 16:1 Compression Ratio methanol fuel World of Outlaws Sprint Car engines don't have any compression?
- fuzzylogic_y2kLv 67 years ago
Yes, compression is absolutely necessary as it compacts the air/fuel charge to deliver more force. Without the compression stroke or compression in the chamber there would be almost no power.
- ?Lv 77 years ago
There are three things that are a must for any internal combustion engine regardless of technology: fuel, spark and compression.
- Anonymous7 years ago
I was giving your idea some consideration, thinking about unique valve timing and supercharging . . . . until I read some of your other questions . . . . . my favorite is the one about wet turkeys flying faster than dry ones.
If you've got some some new no-compression/high output engine design, suggest you talk to one of the car makers. Take a working prototype with you.
- 7 years ago
the injector is only the way fuel gets into the cylinder,
To produce the power the fuel / air mixture has to 'explode' thus driving the piston down. If there was no compression then the mixture would simply burn, when it's compressed and ignites then the expanding gas pushes the piston down producing the power.
- 7 years ago
yes, its the compression that give's you power to move your auto. injection is just the mode of transportation for fuel to be introduced into the cylinders.
- ?Lv 77 years ago
So what are we talking about here..? Gasoline, Hydrogen or something else..? What cylinder head and chamber design..? Based on some of your comments to other answers posted to your question, I'm curious about the basis and/or intention of your original question, too.
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