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Big Block Mopar V-8
Solid Roller Lifter Camshafts
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Hydraulic Roller Lifter Camshafts
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A few quick notes regarding camshaft design for the Big Block Chrysler engines. These engines have a relatively small intake runner volumes to engine displacement ratio compared to most other engines. The small runner to displacement ratio usually generates excellent low end torque and throttle response, but at the expense of top end power. This is why Chryslers have the reputation of being torque monsters, but usually coming in light on horsepower. Ported and aftermarket heads help, but can only go so far with the standard architecture. In order to overcome this, additional duration needs to be added to compensate. Usually it takes about 10 degrees more duration of camshaft for a 440 Chrysler to make power at a certain RPM than an engine of similar displacement of a different make. Smaller B/RB engines don't require quite as much.
Secondly, the intake and exhaust ports on a Big Block Chrysler are fairly balanced in terms of flow - about 75-80% exhaust to intake flow - which is actually really good. What this means as far as camshaft design goes is that a B/RB engine doesn't need a lot of exhaust duration to do its job properly, and single pattern camshafts usually work better than dual pattern cams in these engines. Some rectangle port Big Block Chevy heads can be down around 60% exhaust to intake flow ratio and require 12-16 degrees more exhaust duration in order to optimize performance. This is not to say there aren't instances where a longer exhaust duration on a BB Chrysler engine isn't desirable. Nitrous, forced induction, and certain intake manifolds or cylinder heads can warrant a dual pattern camshaft, as well as high performance engines forced to run stock exhaust manifolds. As always, feel free to call in and we can go over your combination with you and help you select a grind, or custom design one to fit your exact needs.
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