well what breaks the 63-82 vette IRS parts are
- Power
- shock loading
- traction
- and your right foot.
If you have an automatic trans, street tires and don't plan on hard abusive driving- like drag racing and constant hard launches you should be ok with the stock DANA. Would I use one, no way but plenty do. Would I modify one for more power, no.
The iron units are proven, while they also had weak areas over the years, a custom built one will hold up to 1000hp if built using Tom's 12 bolt conversion parts. Of course as the level of build goes up so does the cost.
If I had an 80-82 I would look for a nice 73-79 iron diff with the brackets, 1/2 shafts, strut rods, and TA axle flanges. Build the diff to application- power level, use solid spicer joints, and it will be done. The iron diff will bolt to the 80 cover but you may need to replace the driveshaft or machine it. Plenty have done this conversion with very positive results.
So it really depends on your application, go with what you think will be the final power level, and your honest usage. If you want to talk about how these are built let me know I can go over it with you. If you have the desire I can teach you how to build them.
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