Hi Tim
Yes so the V6 could whilst keeping the banks separate?
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Hi Tim
Yes so the V6 could whilst keeping the banks separate?
Yes, any engine with banks of three: Exhaust systems should be separated.
In it's truest form, each bank of three should have exhaust ports located on the piston thrust side (starboard side for a RH engines as viewed from the top like the Mod50). V6's power is compromised because the banks feed a central exhaust cavity (the tower).
Does anyone care to guess why?
Tim
you gave away the answer ( almost)
A strong hint......... Looking for the technical reason for the phenomenon. Willl give a few days.
Tim
Narrowness. If the exhausts BOTH exited to their port side, the motor would be both wider and non-symetric.
Jeff
Indeed, centralized exhaust is used to keep the engine slender. But the questions is:
Why does one bank produce less power than the other even though they both have 120 degree spaced pulse tuned exhaust?
Try again,
Tim
Okay; the crank is spinning in an opposite directions relative to the charge flow into the transfer ports.
Jeff
corriolis effect?
should you run the engine backwards in the southern hemiphere?
and maybe the bores shouldnt be round?
The Corriolis effect would only apply to engines near the equator, and we all know engines spin backwards down under - LOL - that only means the opposide bank would produce less power. But why?
Tim
Merc used 3 + 3 exhaust tuning on the inline 6's starting with the first gearshift motors. Generally the firing order was alternating pairs for balance with odd/even exhaust coupling (1, 3 & 5 in one group and 2, 4 & 6 in the other). The disadvantage was length between these 3 cylinder exhaust groups favored power in the 5,000 rpm range rather than the 8,000 rpm range.
Its not that it wasn't there, it just wasn't there for super top end.
On the T-2 and T-2x race motors they welded 2 3cylinder 49ci cranks together to get 3 + 3 exhaust tuning with close spacing, 1, 2, 3 in one group and 4, 5, 6 in the other exhaust group. Again there was a problem with length ... the original T-2 set up put them TOO close for 7,000-8,000 rpm. Like these OMC side exhausts ... the T-2X used an extended exhaust chest to drop the tuning into the 7,000-8,000 rpm range and get almost 20 hp over the T-2.