Quote:
Originally Posted by stevey_frac
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.
|
'volumetric efficiency' is my user name on some other forums - i am well aware of the term and its implications.
originally written by me:
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?!
allow me to translate. a large 4 cylinder coupled to an carefully designed efficient turobocharger system (not just the blower but intercooler, a misting system for keeping a heat soaked IC cool, and perhaps even water injection)
will provide you with fantastic economy if driven responsibly but can also
pull like a big engine. as long as you dont go cheap on turbo sizing like most manufacturers do. visit europe if you have the means. lots o lil highstrung engines with turbos. halvofem are diesels.
that explains the "fourbanger as a V8" now i will move on to "forcing it to perform as a twin".
now you take that same fourbanger and instead of feeding it the most and coolest air then splash in fuel to get your stoicio on - or even a lil less for lean burn because you have gone to great lenghts to feed it COOL air you have a margin or error in melting your engine. the result, your engine has to perfom fewer cycles. your have great economy, possibly awesome, and an engine that is maximized (in terms of efficiency and power combined)
add a spritz of water and you can take lean burn to new heights.
eat your heart out honda!
derailed myself again back to my point.
that same 4 be it a V, L, boxer or what have you, now you do the exact opposite of above. now you cleverly cheat it out of the air molecules that it wants so badly to do its job of pulling you down the road. add insult to injury to do all this at the point of risking hurting your engine - in the name of airflow. Heil!
Smokey Yunick, holder of various patents - author of a few books.
yes indeed and in an 80's chevy!!, and no, by heating his fuel only (gasoline)
he provided one of very few brains during the good ol days of good ol boy racing.
when you get your IT preheating worked out be sure to send this guy an email and fill him in on why he failed reaching his 300 MPH goal.
it is the all red firebird, i suggest you do some research on it to see what you can do when you chill your intake air.