no. 1&2 would fire. The next rotation they would exhaust, the next rotation they would fire. That's how a 4-stroke works.
So while 1&2 were exhausting, 3&4 would be firing, and vica-versa. So every rotation of the crank, every 360°, you have a fire stroke.
It's correct that each bank only fires every 720°, but both banks are a phase off, or however you want to look at it. So every 360 it fires.
front fire and then back fire , not each bank.
12 fire, begin power stroke down ----- 34 begin compression
34 fire, begin power stroke down ----- 12 begin exhaust
12 begin intake ----- 34 begin exhaust
34 begin intake ----- 12 begin compression
repeat
the last two actions occur with just the force of inertia from the flywheel. Unlike normal when each compression stroke is powered by one other cylinder's power stroke, that only happens with the second firing pair in this 'big bang' scheme. that is, one pair's compression stroke relies on inertia alone. That's why I suggested you may need more flywheel mass/effect. There's gonna be some increased torsional forces on the crank and flywheel parts too.
it's gonna sound like a harley
Edited by 1 Lucky Texan, 20 April 2012 - 10:35 PM.