I have a 1966 Nova with the 350 small block pushing about 400 horsepower with a 350 Turbo trans with the original 10-bolt rear 8.2 inch gear I was wanting to put a mini-spool in it but I’ve had some people say I need to get a C-clip eliminator kit so I don’t snap an axle. I’m not really going to the drag strip and I don’t have slicks—just street tires. I just want to do a couple burnouts on Saturday nights and things like car shows. Do you think I need to go all out like that or do you think I can just mini-spool it and will it be okay for a while?
R.C.
I will be up front about my opinion on these mini-spools. I don’t like them and would not recommend them on the street. I’m not a fan because while they do work initially, my experience with them is that they don’t last very long. But our experience was with a version with multiple teeth. As you are no doubt aware, the attractive feature is that these mini-spools can be installed easily inside an open differential replacing the spider and side gears.
But there are several downsides to this plan.
The biggest issue I see is the same concern there is for a real spool. The problem is that a spool does not differentiate the distance the outside tire must travel versus the inside tire when negotiating a corner. This places the axles in a significant bind while turning the corner. Eventually this will fail the axles because of this.
This is probably why your buddies said you will need a C-clip eliminator kit to go along with the mini-spool. What you are doing is merely creating a problem that will cause more damage to the rear axles down the road. I’m not a fan of C-clip eliminator kits either because they tend to leak unless the installation is very carefully controlled. Even worse, the C-clip eliminator kits we’ve tried make the conversion by eliminating the stock axle bearing hub. So when the kit begins to leak—you cannot go back to the stock axle bearing.
All of this is an attempt to save money that will only, in the long run, cost more.
Our recommendation would be to just step up and purchase a good limited slip for the 8.2 inch rear axle assembly and be done with it. A limited slip is the solution to all this and will allow the rear tires to negotiate a corner while still putting the power down to both rear tires.
There are several limited slips available for your 8.2 inch rear axle assembly, and all of the best ones are clutch type units. These vary in price by a significant margin. All of these will work very well and should offer excellent durability and give you what you want to spin both tires doing burnouts.
Along those lines, be aware that static burnouts don’t really affect the limited slip very much. However, spinning the car around in circles while doing burnouts—which has become a thing for some reason—is a very different situation.
We had a friend who liked to do these spinning donut burnouts—perhaps thinking he was some kind of hero with his Fox body Mustang. But this came at a price as he soon was complaining his stock limited slip no longer worked.
Another friend’s shop took on the job of repairing the damage. His spinning donuts so cooked the clutches in his limited slip that it required a new carrier to replace all the damage. Plus, the debris from the damaged clutch plates also took out the bearings in his rear axle assembly and it required nearly a complete rebuild to repair the damage. So we’ll just lay this down as a word to the wise about attempting to be some kind of “drifter” hero.
Also, unless you have the tools to set up the new limited slip yourself, its best to have a professional shop do the conversion. Often this may require specialty shims to set the backlash since the ring gear will need to be installed on the new carrier and this will also be a great time to add new carrier bearings rather than try to re-use the old ones from the original open differential. All of this will stack up the cost but it is the right way to do things.
Limited Slip Choices for a GM 8.2″ 10-Bolt Rear End
- Summit Racing Positraction Differential Carrier, 8.2” clutch limited slip – SUM-730962
- Yukon Gear & Axle Dura Grip Positraction Carrier, 8.2” clutch limited slip – YGA-26021
- Eaton Posi Performance Differential, 8.2” clutch limited slip – ETN-19603-010
We do donuts in the ice and snow in Ontario, Canada. It’s a fun way to learn practical car control. Never understood the need to do it on pavement in the summer. Like you said, far more wear and tear than it’s worth.