Thread: Finally

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I just got my 1966 Chevy truck running earlier and am not pleased with the performance. When I give the engine full throttle from any speed and especially low rpm it falls on its face. I have a feeling that it has to do with the timing and the carbuerator. ( the carb is off of my 85 mustang and is a 600 cfm holley) I am not sure if my timing is right on because I do not have a timing tape on my balancer as of yet. So......when I decide to jet the carb how do I know which way to go? since it was jetted for a smaller sized motor....should i start out going bigger? How am I supposed to know the air/fuel ratio I am at??? any help would be appreciated.

Pull the plugs right now and look at 'em. If the porcelain is white, fatten up the mixture. If the porcelain is dark gray to black, lean the mixture. If the porcelain is the color of a cigarette ash with a hint of brown, the mixture is right on and something else is wrong.

There is way more to tuning a motor than this short paragraph, but I'm just trying to catch you before you hole a piston if the mixture is real lean.