starter will spin over. 1980 corvette L48 350 woth 350 automatic transmission..

Optional Information:
Pre-1981 Chevrolet 1980 350L48-350auto

Already Tried:
nothing but starter....starter works off the car, but when I put it own it will not even spin it over at all ..have a now bendix. What could be other areas to look into? wireing is correct to starter!