I have the chance to pick up both or either of these engines, what do you guys think?
1)Running 400 out of '78 Bonneville. $200 including TH400 tranny
2)'72 or '73 455 builder, needs new rods but is pretty complete, recent rebuild before rods twisted. $100 (both are from the same guy)
I recently read in Jim Hand's book that post '76 400's have thinner cylinder walls and are not really desirable, so now I'm torn between the two engines. Also I wonder if there is a possibility to use the crank and/or rods off the 400 on the 455, so I don't have to shell out $800 for new aftermarket rods.
I really would like the original 350 safe on an engine stand.
Thanks, Dave

Put the 350 on a stand and drop in the running 400, then build a monster 455 in spare time. Problem solved (except for the extra money part)

put the 400 to work. save the 350. sell the 455 to me. two people with a problem solved.

Just remember that late '70's 400 is going to be a low compression slug with the original heads!

I would go with the 455 if you dont have the money to do what sixstarved suggested. Cant pass up on a 455!
I am jealous.

By the way, it is my understanding that the rods ARE interchangeable....someone correct me if I'm wrong!

The rids twisted? No damage to the crank? I say build the 455....but I'm kinda biased.

I'm sure you've heard the saying....."there's no replacement for displacement". Believe me there's not! I went from a REAL healthy Chevy 350 to a healthy 455 and the difference is like night and day.

I think I like sixstarved's idea the best, and actually that was what I was planning to do. I already considered the camshaft and head issue regarding the 400. The 455 currently has #15 heads on it (could be either '69 or '70 heads, I haven't checked the date code yet because it's in my friend's garage). Either way, the #15 heads which are recently out of a machine shop would probably be decent on the 400, but I need to buy a cam. What apparently happened with the 455 was that my friend's friend rebuilt it but re-used the stock rods, which were inferior metal. He built it pretty stout and at least one of the rods twisted, possibly breaking the crank as well.
I think either way I'll get the 400 and 400 tranny, and the 455 also. If it ends up I am happy with the 400, I will post the 455 for sale (though I'm almost sure I will want to keep it!)

well if the storage of the 455 is a problem, i know a perfect place for it. lol

i know a better place for it.it should go in a 2nd gen bird

now you know this is a "FIRST" gen board. The only "better" place is in a 1st gen bird. 2nd gen is only good if you dont have a 1st gen. LOL

a 455 never came in a fgf.i like them somewhat original.

that was pontiac's mistake. not mine - not yet

I knew you were going to say that, Terry!
I'm just afraid something might happen to my original engine, and would rather have it tucked away safely with it's lifelong partner, the transmission