alping45
04-25-2008, 08:11 AM
I have an '07 400ex and was thinking of putting in a $20 sparks 6 degree timing advance key as a cheap alternative to a high comp piston.But as I got thinking about it, the key would cause the flame front(explosion) to start pushing down on the piston sooner, meaning that the crank would be at a more vertical angle, creating more stress(wear) on the rod and bearings), right?
Whereas with a high comp piston the explosion occurs at the same angle as stock when the crank angle is not as steep just at a higher pressure.
So, am I missing any aspects of the high comp piston that would cause any more stress than advancing the timing? They both create more pressure, just at different crank postions.
Am I right or not?
And I am also still trying to debate which would cause more heat, the flame starting earlier and getting compressed for a longer period of time when advancing timing, or the high comp piston creating as much or more pressure(pressure = heat) on the compression stroke.
Any thoughts?
Whereas with a high comp piston the explosion occurs at the same angle as stock when the crank angle is not as steep just at a higher pressure.
So, am I missing any aspects of the high comp piston that would cause any more stress than advancing the timing? They both create more pressure, just at different crank postions.
Am I right or not?
And I am also still trying to debate which would cause more heat, the flame starting earlier and getting compressed for a longer period of time when advancing timing, or the high comp piston creating as much or more pressure(pressure = heat) on the compression stroke.
Any thoughts?