> Lean or Rich mixture, which one produce more power ?

Lean or Rich mixture, which one produce more power ?

Lean or Rich mixture, which one produce more power ?

Posted at： 2015-01-07　
You will need to test the fuels in a lab. The fuel that expells more energy when burned will be the fuel that produces more 'power' so to say. That power may not be measured in heat, but rather, how much expansion energy does it produce within the piston chamber? A fuel that burned 'hotter' but produced less expansion energy inside the cylinder would certainly deliver less energy to the wheel of the vehicle than a fuel that produced expansion with little heat. Try finding out what the coefficient of expansion is for each fuel, that may give you the clue you are looking for. Also, try to find out what that coefficient means, a larger number might indicate a fuel with poor expansion.

I can't speak to dry fuels or two stokes but I can tell you for certain that a richer 12.5 :1 air to fuel ratio is pretty much ideal for power in an automotive gas 4 stroke application. 14.7 : 1 is stoich. but that does not yield maximum power, it's the ideal mixture for the catalytic converter



Neither. The ideal stoichiometric ratio of fuel to air should be around 15:1. THAT is where you find the best power for an internal combustion engine.

A LEAN mixture generates more heat and can cause problems with ignition timing. A RICH mixture wastes fuel and builds up carbon inside the cylinder.

Just to add to that run a diesel rich and it runs hotter lean it out it runs cooler

As a rule of thumb, you do a 1/4 turn lean method on the carburetor idle mixture screws with petrol. LPG uses a manifold plate dump with a variable electric gas servo regulator valve so the idle mix is forced into the intake as a vaporized gas. LPG is a great way to power vehicles if the LPG fueling infrastructure is easily available. The engine will run so clean that you could pull the oil pan off at 300K miles and it would look like new inside. Jet Doc is right, too lean and the valves burn up, too rich and it's wasted flame down the exhaust pipe.

Some people say rich mixture produce more power

some people say lean mixture produce more power

which one is true ?

does it matter LPG, gasoline, diesel or carburated, EFI engines ?

for example carbureted LPG engine, stoich 15.5:1

14:1 (rich) or 16:1 (lean) give more power ?

lean means more power and heat

rich means cooler, but LPG is dry fuel

any ideas ?
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