bottom end is in good shape, the heads are 64cc,the old heads were 74cc (i think) and the gear ratio is 4.10 with a posi with a 700r4 trans. it ran good before i just wanted something better thats the only reason i did this. as for the runners idont know what they are. im not a mechanic , im an automotive painter, but the rest of the people that helped me are. and some old drag racing dudes put in theit 2 cents as well. so theres plenty of knowledge here ,maybe i just did something wrong?