trappermike
ArboristSite Guru
Taking advantage of this 2-stroke phenomenon is the holy grail of 2-stroke engine output (horsepower),next to pipes ,it creates a slight supercharging of the 2-stroke crankcase,just like turbocharging or supercharging, we are charging the 2-strokes crankcase at over atmospheric pressure,effectively charging the crankcase with pressure,which of course means horsepower gains. How does it happen?
If the size of the intake port and carb size(venturi) are good enough the size and velocity of the incoming fuel charge at high speed gains enough momentum and speed to create enough INERTIA to overcome everything in it's path,including piston-port spitback,and with it's mass,and speed to create an unstoppable intake charge that RAMS itself into the crankcase disregarding other factors.I have conducted proper vacuum and pressure tests on 2-stroke crankcases at all rpms to prove this,in fact on a good 100cc hotsaw motor I find about 2 psi constant pressure at ram effect,meaning there is supercharging happening. In a 2-stroke bike you will feel it suddenly pulling like hell at a higher rpm.
However you need a good enough carb and intake port size to let enough volume and speed thru,but if intake and carb size is too big velocity will be too slow and ram effect will not occur.
Chrysler first experimented with ram tuning in 1960,it's experiments led to successful ram tuning of race v-8s.
This is free supercharging on a 2-strokes intake,if you get the size and velocity right. My crankcase pressure tests do not lie.
By the size of your intake port and carb you can utilize this power if you have the balance right,max. power at high rpms or midrange torque. If the carb is too small you will create a choking effect(vacuum) and ram effect cannot occur.
If the size of the intake port and carb size(venturi) are good enough the size and velocity of the incoming fuel charge at high speed gains enough momentum and speed to create enough INERTIA to overcome everything in it's path,including piston-port spitback,and with it's mass,and speed to create an unstoppable intake charge that RAMS itself into the crankcase disregarding other factors.I have conducted proper vacuum and pressure tests on 2-stroke crankcases at all rpms to prove this,in fact on a good 100cc hotsaw motor I find about 2 psi constant pressure at ram effect,meaning there is supercharging happening. In a 2-stroke bike you will feel it suddenly pulling like hell at a higher rpm.
However you need a good enough carb and intake port size to let enough volume and speed thru,but if intake and carb size is too big velocity will be too slow and ram effect will not occur.
Chrysler first experimented with ram tuning in 1960,it's experiments led to successful ram tuning of race v-8s.
This is free supercharging on a 2-strokes intake,if you get the size and velocity right. My crankcase pressure tests do not lie.
By the size of your intake port and carb you can utilize this power if you have the balance right,max. power at high rpms or midrange torque. If the carb is too small you will create a choking effect(vacuum) and ram effect cannot occur.