boards to get it onto the wheels... look at the tether, its triangulated against the frame, that eliminates the lateral motion... But I still thing its bogus... "You can fool some of the people some of the time..."
Damn, I started this posted for a few laughs and it turns into a hell of a tech article. Way to go guys!
Apply the brakes on the "rollers". Use melal ramps, make them strong. After tethering the vehicle, release the dyno brake, put the car in gear and slooooowly squeeze the ramps out between the rollers and tires. Use reverse to reinstall. There may be a way to anchor the ramps to the concrete slab. Ya gotta think about saftey, ya know
Looks like it was wired by the same idgit that wired the last car I bought. Give em credit folks. You can only go just so far on 3.2 beer.
this is a very scary version of a ch***is dyno, we use them all the time on winston cup tractors but i don't see all the required pieces here. the strain gage there i worth about $500 and must be fed to at the very least a volt meter to read force, but that force doesn't matter in terms of HP. it really just a measure of how violent the test is. correct application is as follows: typical ch***is dyno uses 2 rollers of very high inertia and large diameter for maximum tire contact area. we know the inertia so all we have to do is measure the velocity of the rollers versus rpm of the motor and through the wonders of an invention called math we can figure torque. hp is merely another equation relating torque and speed. in this scenario - we'll say he can put down 300 hp (sissy) the inertia of that truck axle may be enough resistance to keep from spitting the valve train out. even better if he is running a well pump or a hydraulic motor off of the axle for additional resistance. now we run a car up through the gears into 4th w/ rear wheel speed around 140mph and do a full throttle pull to max rpm which puts rear wheel speed near 200mph and then clutch it. the dyno should have m***ive brakes to slow the rollers back down and do it all over, we sometimes leave it in gear and try to get backdrive hp back its not a very accurate test. we also heavily strap a car down because it will move around on the rollers. i can't imagine how much it would hop on inflated tires - our rollers are steel and about 6' in diameter. can't fault the dude for trying though
[ QUOTE ] look at the tether, its triangulated against the frame, that eliminates the lateral motion... [/ QUOTE ] No it won't - every tried pulling a tree stump with a truck or something? Better yet, a pull off between two trucks? The car will sway back & forth - the triangulated tether may help some, but if it's not perfectly square with each side exactly the same as the other, it will actually induce lateral motion & sway... It's just plain stoopid
Just another candidate for a "Darwin Award"...! I liked the Post with the Gas tank strapped on a tractor wheel much better...! Mark
i see all the required parts for a dyno. properly measured and calibrated, this thing COULD work just as well as any "real dyno". i'm not impressed by the construction, but i sure as hell am impressed by the ingenuity. hell, i'm even inspired. i wanna talk to this guy. David
that 'triangulated tether' needs to be rigid, like a tow bar, not flexible like a chain, to work properly. it will still allow some side to side movement. i think if the chain is short enough, it would prevent the car from wandering all the way off the truck tires. in theory it would work, but the chain looks too long to be safe... tred.
If that contraption works, it'd be real easy to calibrate. Take 2 cars and have them dyno'd on a professional dyno. Then test them on this thing. Record the results and compare with the real dyno tests to come up with a conversion chart for the strain gauge. By using two different cars, you can graph the results and get a reasonably good approximation
and he's probably got plywood or something to cover up the holes around the truck tires. You can tell he's at least tried it because of the wear marks on the truck tires
[ QUOTE ] Where do you guys from Arkansas come up with this ****? [/ QUOTE ] LMAO!!!! Maybe its the generator for the house...2 alternators on each wheel, wired in parallel to the fuse box????
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