a 510 guy out here in Indiana told me he had an 81 0r 82 b310 that he was parting out and wanted to know if I wanted to buy any of the parts. So I had a couple questions.

1. It's and automatic. Is the differential any different from a manual transmission diff?

2. Is there really much of a difference between an a15 and an a14.

3. What parts would be good for me to get?

Thanks a lot.

-007

get the A15 atlest and then get what ever else you might break like the diff ,but im pretty sure there isnt any difference between the diffs ,but the tail shaft could be a different length ?

Yes, the A15 is 7% larger displacement than A14. Same peak HP, but a lot more torque. Means faster acceleration.

1981 & 1982 USA is the low-power engines. Lower emissions.

The underhood plate will list the differential ratio. Probably will be the usual 3.889. See H150

The beauty of the A15 is the fact that the additional displacement over an A14 is in the stroke & as Ddgonzal said, the difference is torque which translates to smoooother driving & better hill climbing.
A bit like a Harley & a Honda. Both will go up a steep hill just fine but the Harley can do it in top gear at much lower RPM, pulling all the way.

Here in Australia the only passenger model to get the A15 was the very late Sunny Sportwagon [WPB310] & the differential in these was the H150B in 3.7 to 1 ratio. [code HB37]
Earlier Sportwagons had the A14 [WHB310] while sedans & coupes came with the A12 & all of these had the H150A differential in 3.9 to 1 ratio. [code HA39]

US models sometimes had the 3.54 to 1 ratio [Code HB35[?]] so check the manufacturers spec plate.