Quote:
Originally Posted by patrickt
....64 is only for pleasant cruising (and the occasional visit to the salt flats  ). |
I'm faced with a dilema regarding this issue. I'm considering the purchase of a used roadster with an engine/T5 combo from a '89 Mustang GT. According to the seller, the car has a 3.70 ratio Ford 9" posi unit. I asked about cruising RPM and found out that the car turns 4K at 70MPH--that is with a 0.68 OD gear, according to this article:
http://www.allfordmustangs.com/Detailed/349.shtml
I'll be relocating to a highly rural area, which means primarily road use with practically no in-town usage, so this is too high for me. A change will have to be made. Obviously, the transmission already has the longer OD gear, so the change will have to come in the differential.
Considering ratios in the 3.2 to 3.35 range, probably at the lower end of that range. Should I replace just the R & P, or go for a totally different pumpkin?
Thanks!
Dugly :cooldude: