Longer is better

Really? For some reason I had it in my head that passenger cars got the shorter ones and trucks got the longer ones. I have used long and short ones with the Napa Gold/Purolator fiters and never had an interference problem.

Kind of have to watch that, since there are different lengths floating around...

The stock one works fine for the stock slant six oil filter, but isn't a good fit for the taller "big block" filter as Reed implies. The taller standpipe transplanted on some oil pumps will not allow the stock slant six filter to even come close to threading on, but is just fine for the big block filter.

-D.Idiot

these oil filters all have a built-in standpipe,
Fleetguard #LF3487 (synthetic media top-of-the-line filter)

A bearded Canadian-American friend of mine just sent me this e-mail:

"There is no "big block" oil filter and there is no car/truck difference. All Chrysler engines got the tall filter (about 5" tall) until 1972 when the shorter filter (a little over 3" tall) was introduced because it was needed for clearance on some V8s with newly added smog equipment. Both long and short oil filters were "Use As Required" items starting in '72. The last version of the \6 oil pump standpipe 3577 848, introduced in 1971, is shorter than the previous version 2402 607. The short filter generally doesn't fit over the tall standpipe, but the tall filter fits fine over the short standpipe. I've yet to encounter any reason not to use the taller filter on any-year slant-6."