OK, some of you may remember I recently acquired an L31 Vortec longblock, and we were discussing what kind of rotating assembly to build. I'd really like to build it "right", but I just don't know that I'll be able to afford it right now, but that's another discussion...

....however, my current "crappy-head" L98 has 180,000 miles on the shortblock, and this "vortec head" L31 only has 60,000. I'm thinking of a straight swap. Drop the heads off for a little machining, throw a cam in, and we're off and running. Well, intake manifold too....hehe

....but of course, I can't be totally sure the block and rotating assembly are good. I vaguely know the guy I bought it from, and he's actually been real helpful in the past, but in the end I really don't know for sure.

....is there any way to tell if it's good idea? Any test I can perform?

Thanks guys.

 

You could do a compression and leakdown test with it on the stand but as far as checking out the rotating assembly there's no way to be certain. Tear it down and re-assemble it before you put it in the car so you know there are no issues. Have everything cleaned, magged, mic'd and magnafluxed then put it back together with new rings, bearings and gaskets if it all checks out.

 

If you don't want to tear it down and rebuild it, i'd just do this
If it's got that few miles on it, it's probably fine. If it holds compression, go nuts. Worst thing that can happen is the bottom end fails, so you put your L98 back in. I kinda doubt that'd happen though.

 

....with that fallback option, I may give it a go.