Quote:
Originally Posted by max_frontal_area
the more air molecules your induction sys can pump into your filling cylinders
the more power you will make per cycle. you can do so by augmenting airflow
with an optimized air intake tract, ram air or some kind of supercharging. or by chilling your intake air. more air molecules even cooler ones than ambient will be compressed and heated during the compression stroke in a gasser but more pronounced in a autoignition cycle. hotter air burns more readily as rudolf diesel found out almost 100 years ago. that in turn allows you to make more power with fewer rpms, think artificially turning a 4 cyl into v8!
lower rpms --> easier to fill cylinders, and empty them reduced reciprocating and parasitic forces, less frictional related heating (on moving/rubbing sliding parts) additional time for more complete burn... i can keep going.
why not utilize a fourbanger as a V8 and enjoy more power, economy and longevity instead of crippling it and forcing it to perform as a twin?!
heat your fuel like smokey did. he got an 80's chevy to give him 100 mpg?
just be careful if gas is your choice of fuel!
|
You suggest that lower RPM translates to easier to fill cylinders. This is true to a point. Modern cars have over laping cams. The intake valve remains open until slightly after the intake stroke finishes. At the right RPM, which translates to the torque peak of the engine, the air in the intake tract has a lot of momentum as it is pulled into the engine, and continues to fill the cylinder as the piston comes back up for the compression stroke.
In engine terms, we refer to how 'full' we get the cylinders as 'volumetric efficiency'. A volumetric efficiency of 100% would mean that you were able to fill the cylinder completely with ambient air pressure. Some cars are able to achieve slightly higher then 100% volumetric efficiency without a supercharger!
As for using a 4 banger as a v8. You lost me. Unless you are suggesting turning your car into a 2 stroke? In which case, you will enjoy increased power at the expense of engine longevity, fuel economy, and emissions. I doubt anyone could make a 2 stroke engine pass modern emissions requirements.
Heating the fuel works great. If your using veggie oil as fuel anyways. Gasoline dosen't have any difficulty vaporizing. Even regular diesel does fine. I've never seen any indication that heating fuel has any significant impact on fuel consumption with good fuel. An otto cycle gasoline motor made of steel is limited to about 37% efficiency. So i doubt smokey got 100 MPG on a car that the EPA rated at 25 without aeromodding the crap out of it.