Camshaft swaps are one of those essential conversions that, sooner or later, every hot rodder will perform. Typically, these stories have always dealt with flat-tappet camshafts, so we thought it would be a change of pace to swap a cam in a late-model hydraulic roller cam motor. These engines are a little easier to work on than the older small-blocks yet also require a couple of extra steps to complete the job.
We chose to work on an ’88 305 with aluminum Corvette heads, but the details around the cam swap will apply to any roller cam small-block Chevy. Plus, while we won’t get into the details in this story, it is possible to install a hydraulic roller cam into a pre–roller cam small-block Chevy with excellent results. The main difference is that factory hydraulic roller lifters cannot be used because there is no provision in the early blocks for the roller lifter “spider” that retains the stock lifters. For these engines, you must use aftermarket hydraulic roller tappets.
The cam we chose for this engine is a Crane CompuCam grind that offers a little more lift and duration (see the Cam Specs sidebar) while still retaining excellent street manners. We also included new valvesprings to handle the extra lift from both the cam and a set of 1.6:1 Crane guided roller rockers. Since we were replacing the stock hydraulic roller cam, we reused the original roller tappets. You can also purchase new factory-style hydraulic roller lifters from Crane if your high-mileage tappets are suspect. Always inspect used lifters to ensure they are in good condition before putting them back in service.
In order to squeeze the major points of the swap into a few short pages, we performed the swap on an engine out of the vehicle. We’ve also already pulled the intake manifold to reveal the lifter valley. Of course you will need to first drain the coolant before pulling the intake manifold and replace the intake gasket when reassembling the engine after the new cam is installed. Now that we’ve set the stage, let’s get to the meat of the swap.