Well for those of you who are not in agreement with the notion that a faster burn is not only better, but essential to a well crafted engine, let me try and prove myself
See the whole point of "fast burn" is that a faster burn, is the RESULT of tuned intake speed, as well as the right dynamics to not only create the proper combustion cycle, but allow ALL of the fuel and air to be mixed. An example used in the book, is that a flame travels like a burning square of paper, and any obstructions (poor mixture) will effect not only the burn pattern, but the area burned, and the speed at which the flame spreads. Turbulence is also very beneficial, because it causes for the fuel droplets to be the smallest and most uniform throughout the chamber.
This is to say, when I say a faster burn is the most important portion of the whole dynamic of the combustion process, I mean that the burn speed is the direct result of how well the motor is using its fuel and air (volumetric efficiency). With that, I then began thinking (the whole reason I wrote this thread). That if our motors need allot of timing (not desirable..LESS torque), then they most likely have slow burn. So the extra timing is needed to complete the burn effectively. This is bad.
Why? (I should point out the following is influenced/cited from HPA publishing "stock car racing, engine technology") 2007:
"Faster burn rates translate into lower exhaust gas temperatures. The net effect is more heat (work) is released within the combustion space. Therefore temperature in the cylinder will be lower at the time of exhaust valve opening."
"The later the spark, the less pressure will be exerted on the piston prior to TDC on the compression stroke"
"This improves "transient torque""
"The maintenance of turbulence until the time of ignition is probably the most important consideration of all, for upon turbulence depends the rate at which combustion takes place"
-That is to say velocity of the intake is less important then ensuring proper turbulence. And no turbulence doesn't mean just slamming mixture into the cylinder, that would cause aggravated mechanical separation of the fuel and air all the way down to the cylinder.
"As ignition timing is increased, so is the amount of negative BTDC work done on the piston"
The article goes on at length about this, but that is enough for me to try and convey my point for now. This article included an interview with Larry Widmer, a renowned engine builder and drag racer, who has countless hours of engine development and racing under his belt. Surprisingly he races imports too...
Dudeman
See the whole point of "fast burn" is that a faster burn, is the RESULT of tuned intake speed, as well as the right dynamics to not only create the proper combustion cycle, but allow ALL of the fuel and air to be mixed. An example used in the book, is that a flame travels like a burning square of paper, and any obstructions (poor mixture) will effect not only the burn pattern, but the area burned, and the speed at which the flame spreads. Turbulence is also very beneficial, because it causes for the fuel droplets to be the smallest and most uniform throughout the chamber.
This is to say, when I say a faster burn is the most important portion of the whole dynamic of the combustion process, I mean that the burn speed is the direct result of how well the motor is using its fuel and air (volumetric efficiency). With that, I then began thinking (the whole reason I wrote this thread). That if our motors need allot of timing (not desirable..LESS torque), then they most likely have slow burn. So the extra timing is needed to complete the burn effectively. This is bad.
Why? (I should point out the following is influenced/cited from HPA publishing "stock car racing, engine technology") 2007:
"Faster burn rates translate into lower exhaust gas temperatures. The net effect is more heat (work) is released within the combustion space. Therefore temperature in the cylinder will be lower at the time of exhaust valve opening."
"The later the spark, the less pressure will be exerted on the piston prior to TDC on the compression stroke"
"This improves "transient torque""
"The maintenance of turbulence until the time of ignition is probably the most important consideration of all, for upon turbulence depends the rate at which combustion takes place"
-That is to say velocity of the intake is less important then ensuring proper turbulence. And no turbulence doesn't mean just slamming mixture into the cylinder, that would cause aggravated mechanical separation of the fuel and air all the way down to the cylinder.
"As ignition timing is increased, so is the amount of negative BTDC work done on the piston"
The article goes on at length about this, but that is enough for me to try and convey my point for now. This article included an interview with Larry Widmer, a renowned engine builder and drag racer, who has countless hours of engine development and racing under his belt. Surprisingly he races imports too...
Dudeman