ali81

i have just bought a 2008 wrangler unlimited, the car had engin swap with hemi 6.1 and supercharger. the transmission is 6speed manual which according to the previous owner is from a deisl jeep and cant take up to 1000hp. the main question is i have to replace the broken ring and pinion which was 4.88 but the mechanic advised me to go for 4.56.
i know that mechanic had never seen a wrangler with such modifications
can anyone advise me what ratio should i choose

Ifstew

What size tires are you running? What type of driving are you doing? Highway, city or off roading?

TheTerminator

With 6.1L and a supercharger I don't see why you need such low gears. Are you running 54" tires??

Canvas

What axles are you running? If you have stock or 44's you will continue to break ring and pinions. I would recommend an D80 (one ton's) at a minimum with that much horsepower. You need a bigger ring and pinion.

R/
Will

BRinSCupstate

With that motor; I'd try to determine what cruising RPM would be optimum with the tire size you plan to run and gear for that RPM. I have an LS 6.0 with GM transmission. I was targeting around 1800 at 70mph with 35". My 6th gear ratio is probably different than yours but I have 4.10.