With the primary guides, chain, and tensioner in place, there’s a special tool that fits on the exhaust gear. With the crank locked at the flex plate, and the cams locked, the gears are in time with the chains on and tensioner retaining pins removed. The idea now is to lock the gears to the shafts. While holding the gears in place by applying counter clockwise force to the exhaust gear, tighten the intake gear bolt to 15 ft. lb. Then get your cheater bars out and tighten another 90 degrees.