I have an 8.2 rear in my Elky and was wondering if I wanted to swap out the 3.08 for a 3.73 or 3.91 gear would I need to change the carrier. I have the 2 r&p sets and want to change it out as cheaply as possible for now until I get the money to do my 12 bolt, also would the ring gear spacer work for mild street driving? Thanks in advance.

The 8.2 10 bolt uses the 3 series differential for the 3.08, 3.73 and 3.91 gears. You will not need the spacer.

Thanks BGH I knew you would answer up. Do they still make the 3.91 gears?

http://www.richmondgear.com/01pdfs/page9.pdf

will all of these fit my 3 series carier?

Yes.

Thanks a bunch. How do they get the 4.10 gear to fit the 3 series carrier is it thicker? That is the one im going to go with any suggestions for pinion depth tool, brand etc. thanks again

Yes, the ring gear is thicker. I don't use a pinion depth tool. I have tried them and found them to be inaccurate. I prefer to set up the gears by reading the contact pattern. This is the most accurate way to do it.

Thanks for the info. I build Helicopter Transmissions and we use the same principles for setting up the gears in them so I shouldnt have much problem with it. What do you use for gear marking compound?

It's a yellow grease that is made just for checking the contact pattern. It comes in the better installation kits.