No, I'd say faulty assumption. The rate at which the driveshaft turns
does NOT, per se, determine the amount of horsepower and/or torque going
through said driveshaft. The rate of acceleration of the machine is a
better way to look at it, since that rate is very high although the
speed is low (for a pretty short time, to be sure). Think about the
amount of torque required to accelerate the dragster in its first
moments off the line. Then think about the amount of work that is being
done to accelerate the machine, which is at its maximum near the start,
apparently at least several g's. Imagine a Model A (rated 40 hp as I
recall) trying to accelerate off the line like a top fuel
dragster--doesn't make sense, right?
Yes, the dragster has slippage in the clutch and tires, losses in the
rear end, etc., but the average horsepower required to do the 1320 with
the assumptions made previously is still about 4400, and it just doesn't
"compute" that less than 1% of that horsepower is used off the line.
Sorry if my explanation isn't clear--maybe Mayf or someone can do a
better job.
Benn
----- Original Message -----
From: "John Burk" <joyseydevil@comcast.net>
To: <land-speed@Autox.Team.Net>
Sent: Tuesday, January 04, 2005 1:29 PM
Subject: Re: Engine config
> Benn - Sorry , error in my math it actualy takes 30 hp to accelerate a
top
> fueler at 1 m/h - At 1 m/h the driveshaft is turning 30 rpm - If the
engine is
> turning 6000 r/m and the driveshaft is turning 30 thats .5% delivered
99.5
> wasted - 6000 hp X .5% = 30 - John
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