S2000 tows like a champ!
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From: Covington WA, USA
Originally Posted by Siepel,Sep 13 2004, 04:02 AM
My niece of 6 is convinced that 1 lb of lead is is significantly heavier than 1 lb of feathers. From some reactions it looks like she is not the only one.
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From: North Austin, TX
[QUOTE=gernby,Sep 13 2004, 07:21 AM] Altiain,
There is no merit to your concern that pulling a heavy load can increase the amount of torque on the driveshaft, half-shafts, ring, pinion, crank, transmission, tires ... or any part of the drivetrain beyond their design limits other than the clutch.
There is no merit to your concern that pulling a heavy load can increase the amount of torque on the driveshaft, half-shafts, ring, pinion, crank, transmission, tires ... or any part of the drivetrain beyond their design limits other than the clutch.
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Originally Posted by altiain,Sep 13 2004, 12:34 PM
Now, if we keep the torque that we're putting into the board the same, but double the resistance of the spring at the mounted end, what happens? The spring stretches less, the board itself absorbs a larger proportion of the energy we've put into it, and the deflection of the board is greater. If you continue to raise the resistance of the spring, you'll continue to increase the proportion of the imparted energy that seeks to find equilibrium in the deflection of the board (the path of least resistance) and sooner or later the board will break, if you imparted a high enough torque to begin with.
You have outdone yourself on this one. This is completely false logic. If you think it through, you'll see that changing the spring has absolutely zero effect on the torque that the board would see. The twisting action on the board is entirely dependant on the torque applied to it, not the spring. If you replace a link in a chain with a spring, does it change the amount of force that the other links see? No.
Do you know why a chain is only as strong as its weakest link? It's because every link in the chain has the same amount of force acting on it. If that force is greater than any link can handle, the chain will break. In the case of the drivetrain, the engine provides ~140 ft-lbs of torque, and every other component (link) in the drivetrain needs to be strong enough to handle it. The only part of my drivetrain that could ever see more than it is designed to handle is the half shafts, since I have 4.77s. My half shafts do get about 16% more torque applied to them than they were designed for. However, they get that when I'm autocrossing too.
I'm not too far from the east side of Lavon (Rockwall). Let me know next time you're going to put it in - I'd love to see it in person!!!
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From: Waikele
Originally Posted by altiain,Sep 13 2004, 07:34 AM
Now, let's remove the rigid mount , and remount one end of the board so that it can spin around its long axis. We will continue to leave the other end free. Now, let's attach a spring to the mounted end in such a manner that the force of the spring resists our attempts to twist the board along it's long axis. Now when we twist the board, what happens? Part of the torque we impart is absorbed by the spring at the other end stretching and allowing the board to rotate, and part of the torque is still absorbed by the deflection or twisting of the board itself. Since the board is not infinitely rigid and the other end is not free of resistance, it will always absorb a portion of the energy imparted upon it.
what will happen is it will accelarate (tangential accelaration) slower. accearation will be half as fast. it will take twice as long to get the same rpm. but the spring will not stretch more.
Now if you increase the torque the spring will stretch more
The equations for Rotation about a fixed axis looks the same as plane motion of a rigid body.
again the drivetrain is not the weak point. It will not experience more stress then a trach session.
what will be stressed out of design limits is the section of the body aft of the rear wheels. the sheet metal is not design for it.
That's why trucks made to tow have leaf spring. the force is channeled from the rear end to the leaf springs, then chassis, then the bumper.
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From: North Austin, TX
[QUOTE=gernby,Sep 13 2004, 12:10 PM] In the case of the drivetrain, the engine provides ~140 ft-lbs of torque, and every other component (link) in the drivetrain needs to be strong enough to handle it.
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From: North Austin, TX
Originally Posted by BlitzSRM,Sep 13 2004, 01:21 PM
The equations for Rotation about a fixed axis looks the same as plane motion of a rigid body.
Now, if there is no resistance at the other end, then there is no distortion. But we do have a resistance at the other end. A resistance that is double (at least) what the system was designed for.