ARC Racing

We at ARC Racing hopes you all had a great Memorial Day weekend. Never forget the ones that made the ultimate sacrifice for the freedoms we all share. We will be back at bright and early tomorrow morning 🇺🇸

We see this way too often, and more than the majority of the time this is caused by an incorrectly installed flywheel key, the wrong height key or in some cases an over lapped or under torqued flywheel. There is a right and a wrong way to install the key in which we showed in our very first flywheel tech video years ago. Here is a short refresher course on how to properly install the key so you get a good mate when you torque it down. The crank taper is angled to fit inside the taper of the flywheel to get proper mating during the torquing sequence. However, the key should not follow the angle of the taper. Instead it should follow the alignment of the actual crank shaft and be slightly angled in the taper as shown below. Also many don’t know that diffent height keys are available for these engines. In a pic below we show the two different height keys that have came in the many different styles and name brands of these engines over the years. Unfortunately if someone has multiple engines in their shop and grabs the taller key for a crank that uses a shorter key, catastrophe can happen. If the key is too tall or not in the correct angle the back side of the key will be too high and not allow the flywheel to proper mate with the crank taper and will cause it to slip and shear the key ultimately damaging the flywheel and crank. Light lapping is also recommended before installation using a medium to light valve grinding compound for a maximum of 20 or so seconds. No more is needed because too much lapping can change the size of the flywheel taper enough to hinder tje toque sequence. Proper torque specs for all ARC small block flywheels is 65-70 ft/lbs, and all ARC ultra lite flywheels is 54-55 ft/lbs. If you have any questions please contact us at 800-521-3560, [email protected] or message us here.