I don't think you will like that 3:91 gear with a low first gear 3:09 ( if that's the 4 speed trans you have going in ) I tried it >>>>> you'll get tired of shifting too early thru the gears and not going anywhere . freeway rpms will be too high for comfort . I had 27" tires on mine . did not like that 3:91.. so I put the 3:55 back in . but that is just my opinion .