I have a '71 with the high compression 351C (180 - 190 lbs. in all 8 cyl.), stock except Edelbrock aluminum intake, 600 Holley (vacuum secondaries & electric choke), and electronic ignition (Ford dist. with Accel coil). Had to back the timing off to 1 degree BTDC to get rid of pinging on Sunoco 94 octane, which is the best stuff we can get in Canada.
Not happy with the power characteristics with so little timing advance - feels lazy. Will octane boost or other fuel additives help, i.e. will they allow more advance without detonation? If so, which should I use and how much more advance can I dial in (I know 6 degrees nominal is stock)? Do additives separate from the gas? Any side effects from using octane boost or other additives? I currently use a lead substitute - can I continue to use it with octane boost and is it necessary? Will it mix with octane boost?
Do you have any other suggestions which might help me deal with this detonation issue (e.g. will colder plugs help - I use the stock recommended heat range/plug for '71 351C - ASF42C Ford/Motorcraft). I don't really want to lower the actual compression ratio or mess with the internals too much.
Thanks very much in advance for any help you may be able to provide.
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