Engine Parts Swappable From 3100 LG8 to 3400 LA1

[TazMan]

So I inherited a 99 Grand Am with 210K that has an engine knock that sounds like it's coming from a lower bearing. There's no smoke or anything like I'd have expected from such mileage, so, I filled it up with some Lucas which quieted things down and have been driving it around a bit, and it drives very well.

I also have an almost complete 3100 with about 95k sitting on an engine stand in the garage. I don't see dropping a bunch of money into a car with 210k, but I was thinking of just swapping the crank, bearings, heads, and intakes from the LG8, right into the Grand Am since I have them. Well maybe new bearings since I'm there. Are there any other parts swappable? Camshaft, pushrods? Does anyone advise against this? I figured I had the parts here so all I really have to lose is some time and maybe some gaskets if the motor doesn't hold up.

[Guest]

I understand swapping the crank and replacing the bearings, to repair that rod knock (as it sounds like you might have) issue, but anything else would be a waste of time, since the valve train is all the same between them, you won't gain anything by swapping any of those parts, except for maybe slightly lower milage parts, which in my experience has not been an issue with these engines.

[TazMan]

Really? Yes, I was replacing the other parts for the lower mileage parts. I figured if there was enough wear to wipe a main bearing then who knows what's next. You think just swap the crank, replace the bearings and I'll be good to go?