Could a modern inline eight gasoline engine be competitive with other designs, especially for high performance applications such as a limousine or supercar?
Didn't the long stroke/small bore have something to do with tax? I think that tax was linked to bore size which promoted longer strokes for the same displacement.Duesenberg DOHC Supercharged Straight 8 had long stroke, small bore
1948 Buick 320 (144 hp) Inline 8 Engine Bore and Stroke: 3-7/16 x 4-5/16
Just about all the straight 8 engines I looked up had small bores and longer strokes which can not compete with V8 horsepower.
That's kind of what I was wondering about. Wikipedia hints at the crankshaft being a weak point of the design, especially at "high speeds." Presumably that explains why there are still inline eight diesel engines, but wouldn't the crankshaft issues still emerge in a V16 gasoline engine?Would another factor be the in-line's longer crank-shaft compared to the V's ?
A straight-eight can be timed for inherent primary and secondary balance, with no unbalanced primary or secondary forces or moments. However, crankshaft torsional vibration, present to some degree in all engines, is sufficient to require the use of a harmonic damper at the accessory end of the crankshaft. Without such damping, fatigue cracking near the rear main bearing journal may occur, leading to engine failure.
Although an inline six-cylinder engine can also be timed for inherent primary and secondary balance, a straight-eight develops more power strokes per revolution and, as a result, will run more smoothly under load than an inline six. Also, due to the even number of power strokes per revolution, a straight-eight does not produce unpleasant odd-order harmonic vibration in the vehicle's driveline at low engine speeds.
The smooth running characteristics of the straight-eight made it popular in luxury and racing cars of the past. However, the engine's length demanded the use of a long engine compartment, making the basic design unacceptable in modern vehicles. Also, due to the length of the engine, torsional vibration in both crankshaft and camshaft can adversely affect reliability and performance at high speeds. In particular, a phenomenon referred to as "crankshaft whip," caused by the effects of centrifugal force on the crank throws at high engine rpm, can cause physical contact between the connecting rods and crankcase walls, leading to the engine's destruction. As a result, the design has been displaced almost completely by the shorter V8 engine configuration.
There are 2 pistons per crank throw in a V-engine. The second piston acceleration probably helps counteract the effect created by the first piston acceleration.Presumably that explains why there are still inline eight diesel engines, but wouldn't the crankshaft issues still emerge in a V16 gasoline engine?
Yes, the way evolution is controlled by rules is interesting.cosmik ..this is why i love this forum!
tax the bore stroke ratio...dont say this too loud in the blue states over here
here is great link to why British sports cars were long stroke while the European models were high revving
...the long stoke small bore Usually means lot of torque but low rpm
and that long skinny crankshaft ..to do anything over 5000 rpm would scare me!