Chasis Dyno Tuning is A GOOD THING!!

[RICK LAKE]

Both J's You guys are trying to use a shotgun to kill a mouse. There are alot of things you have to take into account. Is the car on or off the ground? Are tires on it? Are the brake pads dragging or touching the rotors? Are the wheel bearing too tight or loose? What kind of tires are you testing with? 10 year old rocks or gummy slicks? I believe you are both right to a point. I think it takes about 20HP to drive the trans and rearend with tires on it up in the air. This is with a posi unit. You put this car on the dyno or street and run it the same way, with tire drag and everything else, about 16-20% of total drag on the motor. You also need to figure out total load on the motor. I would think it is alot easier for a torque motor at low rpms to have an easier job of spinning the drive train than a 600hp motor at 7,000 rpm with no bottom end. The exhaust is another HP killer on cobras. The idea backpressure is about 1-2.5 pounds+ of psi at WOT depending on the motor and size of cam. nything more and the exhaust is costing power. You will also pickup about 10-20 honest HP with a set of webers setup correctly over any carb on the market in the mid range rpm's of the motor. Just my 2 cents. Rick L.