Hey everyone I have a 9-bolt rear from an I-roc and i want to bump up the gear ratio just don't know where to start looking for it. Its stock posi unit i believe 3.27 are in it i would like to go higher. If anyone can let me know where to buy the gears or have any other suggestions let me know. I'm located in north NJ.
Enrico

 

Most common step up is 3.45 and 3.70 but the 3.70 gears were not in a production car. Gears and other parts for the 9 bolt are hard to find. The diff comes from Australia where there are lots of parts for them.

The 9 bolt was only available for 3 years in the f-body and only in certain models. Since there's isn't a high demand for parts other than bearings and seals, nobody carries anything.

Many times it's just easier to swap in a 10 bolt for better gears, posi etc.

 

I wouldn't be worrying about gears just yet. 3.27 is just fine with what you have for now. just be thankful you don't have that awesome 2.73 open rear anymore.

I'd go with a cam, torque converter, and full exhaust before i'd even consider worrying about a gear swap. much better bang for the buck. get rid of the weak links first.

 

Sites for 9 bolt gears:

Jawsgear

Justdifferentials

Accuautoparts

I haven't used any of these sites. If you have 3.27 now, the 3.70 ratio will be a nice step up.

 

I ran into the 11's with 3.27 gears.

 

I started last month i put in a new cam timing gears new intake bigger throttle body with spacer new lifters 1.6 roller rockers new pushrods full exhaust with cut out so i have a good amout of stuff so thats y i want to pump the rear up.

 

Thanks for the sites unfortunally i am kinda in the blue when it comes to buying the gears which ones from which site would you recommend also wat else would i need to purchase to put them in correctly. Thanks for the help. Enrico

 

You'll need a master installation kit(bearings, seals, shims, etc.) to go with the new gears. Justdifferentials sells the installation kits too IIRC. If you've never done a gear install, you really need to find someone who's experienced to help you, or pay a shop to do it. It requires some specialty tools and is definitely not a job for a novice.

 

If you are "kinda in the blue" forget about trying to bump up your rear until you do a little more research. Not the the DIY project that can be answered in one or two sentences. Just my opinion.