An Old Cam Profile With A Modern Approach

8/1/2024

If you are someone like me that has been around for a while, you probably remember the 1960's and 70's and the muscle cars of the time. I was 20-years old in 1975. I liked cars but I was more into Harley-Davidson motorcycles. It took less money to work on and build Harleys. I was building a 1949 Panhead chopper at the time. This is also the same year that I started grinding camshafts for Reed Cams, Inc.

Chevrolet, Ford, and Chrysler were all producing small block OHV V8 engines with more power than ever before. Big block engines were also being installed in cars. Each car Company had their own line of performance parts that were available to the public. Each Company had a following of fans that knew the best part numbers for each component. Engine blocks, heads, crankshafts, rods, and certainly camshafts. One of the popular Chevy 350 performance camshafts of the day was the GM 3849346. Also known as the "30-30" camshaft.

I have created my own design based on this camshaft with a modern approach. With this lobe design the camshaft can be manufactured for a flat tappet or a roller tappet. The tappet can also be a hydraulic or a solid. The lash is .009-inch for a solid tappet. The ramp designs are much better than the original .030-inch lash ramps and deliver the same running duration numbers as the original profile. The original camshaft was ground on 114-degree lobe separation with maximum lift at 112 ATDC on the intake and 116 BTDC on the exhaust. You can choose whatever lobe separation and indexing you would like based on your application.

Below is the tappet lift table in an .s96 format that will allow you to have the camshaft manufactured. Download the file and send it to your camshaft grinder. Give them the lobe separation and whether you want a flat tappet or a roller tappet camshaft. The Chevy 350 base circle diameter of the lobe is 1.220. The roller wheel needs to be 0.750. Get the correct tappets and you are ready to go. A data file of the profile is also listed. Let me know how the camshaft works for you.