I've seen that a 1971-72 Road Runner has a 115" wheelbase and that the earlier Road Runners/Satellites have a 116" wheelbase. My question is, in theory, would a driveshaft out of a '71-'72 Road Runner work in an earlier Road Runner with the shorter driveshaft?

I'm assuming here that the later driveshaft will be an inch shorter than the earlier ones, but will that make a huge difference for just a driver?

Thanks

There's so many variables from the stackup of tolerances in the driveline that you'd want to mock it up (yoke all in/measure C to C /subtract 3/4") & go from there.

If it was an extra 1" shorter than what is nominal, would that impose a problem? I'm just asking based off some thoughts here. I know I need to get the right thing, but I'm just curious if anyone has had more "slack" than what's nominal before and if it caused a problem. I seem to be having a VERY hard time finding a driveshaft for my '68 Satellite. I have the original one, which I could cut, but it's not as beefy as the BB driveshafts. Whether that makes a difference behind a mild 383 or not is something I don't know.

In your situation I'd mockup/cut the longer shaft that you have on hand & you'll b fine w your mild 383 & it'll get you up & running quicker (or on to the next prob quicker). EDIT to ans your Q mockup that other shaft & post how much clearance you get

Thanks, it will be a few weeks before I get to that point since my block is still at the machine shop.

Will the yoke from the original driveshaft (318/904 set-up) work for a 727? Or will I need to cut the driveshaft AND get a 727 yoke?

Thanks

you will need a yoke. A 904 yoke is not interchangeable with a 727 yoke.

You'll need to grab a 727 yoke & just check the inside to inside measurement between the ears on it & want 3&1/8 (7260) or 3&5/8 (7290) to match the same dimention on your intended shaft. iirc 4 sp yokes are the same (as a 727) but cant confirm that as I am not a 4 sp guy