Join Date: Mar 2007
Location: Western North Carolina
Load on mains
The early firing order puts a little more load on the front mains by firing cylinder 5 right after 1 in the sequence (both are up front). 5.0 HO and 351W firing order better balance the main bearing loads. It probably doesn't make a huge difference in power or stress on the crank but I suspect Ford thought it was worth something in the HO motors. Its obviously more important to get a cam with the right lobe profile than firing order. I currently have an early 302 with a mild performance cam that has the 351W/5.0 HO firing order. FWIW, it does seem to run very smooth in my opinion.
1970 Mustang Sportsroof, Metallic Gold, Ginger interior
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