Taking my bike test soon :)
Join Date: Sep 2008
Location: 51?51'23.70"N 2?15'37.61"W
This doesn't seem to make much mechanical sense. A motor is like an air pump. Within reason, more air and more fuel -- more power. Larger valves coupled with head work should allow more air into and out of the combustion process. Can someone with experience provide a more technical response?
Yes BUT what air can your cylinder draw? You can have all the flow in the world but if the cylinder won't draw it you have a problem. Test head on flowbench, modify, add 20% flow but how about this for a thought - the stock head already had more flow than the cylinder could draw. All you are doing is making the air flow worse. Airflow on flowbench and engine are not the same. Put a 300cfm draw on your head on the test bench you flow and AIR SPEED are great, now put that on a cylinder that will only create a 150cfm draw and you've halved your air speed because the port is now too big. Its all about optimising and most people haven't got a clue how to do that. There is no guesswork in this subject if done right.
Yeah forums suck, they've all gone quiet. Probably because most people have been laid off!!
"Engine builder for the worlds fastest Skoda - 227mph, Bonneville class record
"One mans ceiling is another mans floor" - Erland Cox.
"Don't judge me by your ability" - Clive W.