Factory set timing for 4.9 is 10. It is recomended 6 if regular gasolin is used.caddeville said:What would be the best degree on the timing for my 4.1? I run unleaded 87 octane fuel and want to set my timing to the best degree for the best performance. Msd EVERYTHING will also be installed around mid december. Already installed new plugs yesterday, msd wires will be next weekend.
I set mine at 8 and burn 89. Great power and fuel economy! I am not sure but same settings seem to be eligible for 4.1.