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A technical bulletin from Comp Cams and the recommendation from Crower to use high zinc content oils for break-in of flat-tappet cams comes in response to the growing problem of cam failure during initial break-in. Joe Gibbs Driven BR is the only fully formulated oil designed specifically for breaking in flat-tappet cams. The high zinc content formula has been used to break-in every flat-tappet Sprint Cup engine built here at Joe Gibbs Racing for the last 6 years. In fact, the development of BR reduced the number of camshaft failures during break-in at JGR from 1 in 10 to 1 in 40.
Proper preparation of lifters and cam lobes by polishing both the lobe and lifter foot aid the break-in process and futher reduce break-in failures. It is also critically important to ensure proper parallelism of the cam lobe and lifter. For improved break-in success, we recommend that you use our Engine Assembly Grease to coat cam lobes, lifters and pushrod tips during assembly. Then use BR petroleum based break-in oil during break-in. We also recommend that you use a tape of chemical polisher to improve the RA finish of your cams and lifters prior to break-in. Some companies sell pre-polished products, so you don't have to buy the equipment to do it in house. Again, there is no substitute for proper lifter to lobe geometery, so once you put the right pieces in the right places, you now have the right oil and assembly grease to protect you investment in time and hardware.