What are the exact differences in distributors

[models916]

What makes the sbc bbc distributor different? All I know so far is it is longer than the W distributor. On the side, what is the difference with the W truck distributors?

thanks guys

[SteveD409]

The truck distributor has a governor on it.

[Johnny Impala]

I think it's just the length that's different with a smallblock dist. When I was putting my 348 together, I could'nt find a good 348 dist. so I used parts from a small block one to fix the 348 one. The only part used from the 348 dist. was the housing. I used the vac. advance, mechanical advance, and the dist. shaft and drive gear from the small block dist. The small block shaft had to be shortened, and the end remachined to be used though. If wasn't difficult to shorten either. The guy at the local machine shop only cut it off and milled the end to the right shape, cost about $20. The small block shaft wasn't even hardened from the factory. This was only a single point dist. however.