I was planning this 400 build for my 55 Pontiac Chieftain and thought I had the motor locked down. I had been talking to a partner from way back about this Poncho motor he bought from a bone yard I was workin at about 15 years ago. Turned out dude still had it and didnt have any plans for it. I told him I wanted the motor and would come pick it up shortly, this was about 2 months ago, I waited too long! Dude had the motor and tranny sitting in the back of a 65 F-100 in the back of his property and finally decided it was time to get rid of all the "shit" laying around the place. Truck, engine, and tranny all went to the scrapper for the price of steel. Didn't even bother to call a dude before he drove 4 hours to come get it! I would have took all three and paid better than the crusher. Bummer. So now Im on the hunt for another 400 at a white boy price. Preferably the 9790071 or 481988 cast# blocks, complete, running, hooked to a 4-speed, Im open to whatever. Throw me a bone, if Im hungry enough, I will bite. " Im a low life trying to live the high life...and a hot rod helps!"
I have found that if you want it get it now or if you wait its gone,I had that happen to me a few times when I was a little late in picking up what I wanted. If you dont come and get it with in a reasonable time they think you dont want it.
400's are pretty common... unless it was a GTO 400 with Ram Air heads...well that's a diff story... Btw do some research on 400 blocks, some are pretty weak and not worth building.
You are correct....the rule of thumb is they are all OK EXCEPT casting # 500557. The 557 block was '76, '77ish and has a thin main web area where the main cap dowel is drilled. Here is what they look like when you start putting power to them... There are a million other Pontiac guys who have just about the same exact picture missing almost the same exact chunk. That is just where they brake because of the thin web area and the dowel pin drilled through it. Good luck, -Abone.
The Jalopy Journal
