quote:Originally posted by brother-bee:
Comp2. Could you go into more detail on pairing of wrong cylinders.
Looking at the headers as constructed.
On the right set cylinder 1 is paired with 4 and 2 is paired with 3.
Firing order is 15426378
Look at the exhaust ports from these two:
notice cyl 1 and 2 is expelling burning fuel. 1 and 4 is paired.
4 fires then 2,6,3,7,7 fire then 1 fires the time it takes 5 other cylinders to fire all back pressure is gone in the primary
After 1 fires, 5 fires then 4 fires. Cylinder 4 competing with the same exit as 1 has 1/5 the time for evacuation keeping back pressure in the tube.
The ideal pair would be:
1-6
5-3
4-7
2-8
The only way to do that would be to create a cross over pipe from the left back to the right bank to pair appropriate cylinders; thus a huge advantage of 180's
Contrast that