Due to the EPA's mandate for zinc removal from most motor oils, proper flat tappet camshaft break-in procedure is more critical than ever before. This is true for both hydraulic and mechanical flat tappet Camshafts. As a point of interest, the most critical time in the life of a flat tappet camshaft is the first 20 minutes of “break-in” during which the bottoms of the tappets “mate-in” with the cam lobes.
There are some oils with additive packages that are better for camshaft “break-in”. These include, but are not limited to: (Brad Penn or Joe Gibbs racing) or a “race only” petroleum- based oil and include Crane Cams
Part # 99003-1 Super Lube” additive.
.........."Do not use API rated “SL” or “SM” oil"............
CAUTION: We do not recommend the use of synthetic oils for “break-in”. Prior to installing the camshaft and lifters, it is recommended that the crankcase be drained and filled with new, clean oil, as listed above. The oil
filter should also be changed at this time.
You can also use: Mobil 1 15W-50 (1,200 ppm), Mobil 1 0W-40 (1,000 ppm) and Mobil 1 High Mileage 5W-30, 10W-30 and 10W-40 (900 ppm).
Stay away from: API SM/ISLAC GF-4 oils They are for for better fuel economy and for the protection of catalytic systems with lower phosphorous (800 ppm).They are not good for our cars!!!!!!