MI Pulley Black and Red Colors!

[CrankyOldMan]

Originally Posted by cali yaris

Lightweight rotating elements, like pulleys, flywheels, and wheels/tires, confer more responsiveness and feel than actual measurable horsepower, but it is a noticeable difference.

Doh. I oversimplified the result. You're not actually adding horsepower, you're just removing parasitic losses. The net result is that your acceleration curve as a function of time has a steeper slope. I don't think it would show up on a dyno, since that is hp/torque vs RPM, not time.

For racing purposes this means reaching the power band sooner--so your elapsed times will decrease. For daily driving, this means less energy spent spinning up the pulley--decreasing fuel consumption.

I frequently have issues with acceleration wheel spin (outside of ideal road conditions) and my only other engine mod is a drop-in high-flow filter. I can only imagine what a lightweight flywheel and I/H/E would do. Perhaps it would require me to add that magical LSD?

[imike929]

how easy of an install is this for say...a beginner? lol

[jpmck03]

Originally Posted by imike929

how easy of an install is this for say...a beginner? lol

It's not too bad. Jack up the car. Put it on jack stands. Take off the front passenger wheel. Pop off the wheel well panel. Remove the old pulley. Put on the new one. Put everything back together.

There are a few links in my sig on how to install it and a review of the pulley itself.

[tooter]

Originally Posted by CrankyOldMan

Doh. I oversimplified the result. You're not actually adding horsepower, you're just removing parasitic losses.

I think it would be more like removing inertial force. The motor would work harder to get the heavier stock pully spinning, but the stored inertial energy in the pulley would resist slowing down.

The net result is that your acceleration curve as a function of time has a steeper slope.

Yes, both the acceleration and deceleration curve would be steeper because of less rotating mass. Essentially a similar effect to a lightweight flywheel.