Stalls when put in drive or reverse
 

Ok I've got a 87 Monte SS, it sat for 10 years and the previous owner pulled the 305 and put a 350 engine in it.

it runs and will drive, but the only way to get it into gear is to step on the gas and brake and the same time.

we have done new plugs, wire, cap and rotor. Brake lines and all new brake parts.

gas was drained and tank was refilled with gas and dry gas mix.

any ideas why it's stalling out?

thanks in advance

What about the fuel filter that should be changed, and you might want to look at the Catalectic Converter it could be plugged. Also change the Air Filter.
Catalectic Converter I would bet on this I owned an 85 once and it did the same thing it was the Cat.

Sorry forgot to say no cat, they ran duel straights and there's no fuel filter on it.

What carb are you running the original quadrajet? Sounds like bad gas in the carb. Could be bad gas gumming up the carb if it sat for ten years with gas in the bowl.

I agree carb prolly gummed up

Thanks guys I'll clean it today and see if that helps