Grn92LX said:If you're going to switch, 410's are what you want. No offense but this isn't rocket science. The difference on the hwy between a 390 and a 410 is maybe 100 rpm's. Your heavy very needs the gear. Like I said, i'll be doing 430's in my pump gas street car and yes it see's the highway
as i posted, im more concerned with the 1-2 shift rather than hwy speeds