That went fast because of torque. As once said, something to the effect that if electric power was so great then every body in drag racing would be running geared-down drills. And not to through mud in your face just going to compare since this is a train forum, but there is also a diesel powered dragster out there that runs the 1/4 in the high 6’s/low7’s. They are currently working on getting it faster [:)]. As long as money is no option, you can quite easily go out and buy an older Dodge ram with the Cummings 5.9L turbo diesel and have it ramped up to around 800-900 hp and still be very street able. Torque? Go put a diaper on first. Torue in the particular truck I am thinking of is 1400 lb-ft. Just to compare, the typical 12-13L turbo-diesel in semi’s makes around that much torque, mind you I am talking about a 5.9L. There was also a Ford that was juiced up to 1400hp, but it also had every possible power increaser made for Fords. NOS, twin turbos, methanol injection, power programer, semi-truck sized exhaust, aftermarket pistons and guts, cam, on lets see oh yea fuel injectors and fuel pump. Also on a side note your typical car/truck fuel pressure can go from 45psi (older chrysler) to 65psi with fuel injection. Typical direct injection modern diesel engines can see upwards of 23 000psi. Makes me wonder how much water pressure those water jet machin
Not quite. The valve uncovers and covers ports at the side of the sleeve, or cylinder, in which the valve slides back and forth. When it uncovers an inlet ported to the dry-pipe, incoming steam pressure is governed by the pressure in the dry-pipe, not by what the valve lets in or out. The volume of gas is indeed controlled by the cut-off, or timing (the duration that the valve allows the port to be uncovered). Pressure is essentially instantly to the max and then it begins to expand agains the only movable part presented to it…the piston face. By then, ideally, the valve has closed the port again so that the volume admitted can do its expansive effort.
Volume and pressure are directly related. So, the pressure on the piston face imparts momentum to the piston rod, to the crosshead, to the main rod, and around the main crank. The distance from the center of the mainrod crank pin to the axle of rotation of the driver is what imparts the torque on that axle via the force tangential on the crank pin and parallel to the axis of movement of the driver.
What makes for a torquier steam engine (a drag freight tank engine, say, versus a high-drivered 4-4-0) is the diameter of the drivers as a ratio of the amount of rotational force the main crank can generate, which is itself a function of the distance away from the axle. If you have a large throw on the main crank and tires on the drivers just outboard of the circle in which the crank turns, you will have a very powerful set of driving wheels. As you increase the diameter of the drivers, thus makin