I am getting ready to install a posi in my '64 Wildcat. The plan is to use the original 3.07 gears with the posi unit that also had 3.07 gears. I have some of the special tools to do this but do not have the spreader tool that allows the carrier bearings to be easily removed. I am hoping to use shims to spread the carrier housing or some other method with common tools. I am also hoping that the original shims will give me the proper backlash and gear mesh pattern. Does anyone have any sage advise or experiance with this? Shims for the '64 axle are not easy to come by. I may have to make my own, if needed.
I don't know if this qualifies as "sage", but I would advise against a change to posi without making a significant change in gear ratio at the same time. If you are happy with the 3.07 gearing, there is little to gain for normal use.
Mark, I gather you are trying to install your existing 3.07 gears on a posi carrier? If so, I wouldn't count on your original shims working. Due to the inherent manufacturing tolerances of the carrier and its components, even a slight change would impact the backlash. Unless you got a helluva deal on the carrier, a complete post third member might be a better choice. There was one on eBay not too long for for about $500. Just my thoughts, good luck!
Yes, I got a real good deal on the posi unit. I had looked for a complete center section but the price plus shipping was at least double what I have in this nice posi unit including shipping. I do have an ace in the hole as I will have the guys in our inspection dept measure the current carrier and the posi carrier to see what the differences are for the critical dimensions. I can also have the shims water jet cut for just the cost of shim stock if needed. My kicker is that my best friend is a MFG engineer at a Meritor axle plant and all he does all day long is oversee a ring & pinion gear lapping and assembly line, so he is well versed in how to set up R&Ps, although the smallest one he works with is about double the size of my 9-3/8" gears :laugh: i'll admit the posi is a want and not a need, but with the lower profile tires (255/60R15) I am running the effective gear ratio is more in line with a 3.37:1 axle ratio (2300 erpm @ 60 mph).
I'm not a huge fan of posi either. I have it in about half my cars and would say that at the dragstrip and boat ramp it's a plus, and not so much otherwise. I just hope your 'pro' is able to get you through this ok and you don't end up with a car you can't drive-good luck
