7 1/4 VS 8 1/4

I have a 68 dart with a 7 1/4 with Small bolt pattern axles. I want to convert to BBP, for rim selection etc.

I understand there are 8 1/4s, came in Dusters and the like? That have BBP and will bolt directly in to the 68 with same hub to hub width?

I have ignored this axle my whole life because I usually build hot rods, and go right to the race axles. My 67 has a Dana 60 in it, for instance.

So I know nothing of these axles, but I think there are a few on the island I can get at a reasonable cost, as the guys I know that have them all are hot roddders too and go right for the 8 3/4.

My Dart will remain a mild /6 the rest of it's life, so I don't need a posi or a super strong heavy duty axle, I am mainly shooting for good brakes and the BBP and good size wheel studs.

Can I get a break down of what will fit in my dart if I can find one?

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