I have a 54/3100/235 with 2 rochesters and dual exhaust and a nova 2.73 rear end also a t-5 tranny.. i was getting 12-13 around town until put in E-3 plugs and it jumped 25%. as far as 53moneypits comment. i have gotten as high as 24mpg and i have the records to prove it. no it is not usual but i have averaged over 20mpg on my trips to Kansas City. i also had a witness, JDL. that said with a original set up i would say 12-15.
Last edited by WE b OLD; 11/15/2011 2:41 AM.