1972 El Camino 350 4brl, TH350 Auto, when in drive idle is about 200 rpm low, and it sputters and dies when I try to accelerate from stop. After reaching about 1200 RPM it runs fine.Where do I start, fuel filter maybe? Bought it one year/8,000 miles ago, have only adjusted timing and mixture since then (about 3,000 miles ago).

It sounds like a bad accelerator pump in the carb. Remove the air cleaner with the engine off. Check to see if the pump is squirting when you work the throttle by hand. Be sure to set the idle RPM where it's supposed with the transmission in park.

If the pump seems to work okay, let us know because there are some other things you can check, but the pump should be checked first. After this, it gets into secondary air valve adjustment or chasing down vacuum leaks.

Removed air cleaner, can smell gas and notice a new stain on intake manifold in front of carb, looks like dried up gas. The carb does spray gas when I move the throttle.

Ths smell and stains indicate that this could be a flooding problem. The stumble and hesitation could be caused by engine either running too rich or too lean. Have you noticed any black smoke coming from the exhaust?

And.....if this is a Q-jet carb, then the float bowl plugs on the bottom of the carb may have started leaking, which would explain the fuel smell. Most people seal them up with epoxy. PC-7, available at most hardware stores, would work fine for this.

Come to think of it, all you may need is a carb rebuild. Be sure to replace the float when you rebuild it. Floats are sold separately