Hi,
Ok. I have a 69 GMC step side with a 350 crate motor, mild cam, Edelbrock manifold, Holley 650 with vacuum secondaries. Its a daily driver with occasional pedal to the metal runs. Anyway, when I'm sitting at a light I notice a rich smelling exhaust yet when I take off it moves!! I've checked the fuel levels in the bowls and it is good. The plugs look perfect. Any input or suggestions about this would be appreciated. Thanks

 

If your plugs look good and it is running well than I would leave it alone. It may just be that you are used to smelling the newer catalytic converter equipped vehicles. I had a 1965 C10 with about the same set-up that you could smell at idle, but like yours, it ran fantastic and the plugs were a nice tan color. If it's not loading up at idle than you will be fine. Just hold your breath at the stop lights .

 

Thanks for the input. I will do just that, nothing. It runs great so I guess the saying "if it works, don't mess with it" applies.