know where to find a 406 long block, i cant find one anywhere?

 

I've got one.. Was building it for a boat, flat top pistons, new 76CC heads, RV cam, everything ready to go, What state do you live in??

 

im not looking to purchase right away, was just checking out prices and seeing if my best option was to have a local shop work on it of see if there was a good choice on the internet. I had a bad experience with buying a motor someone built in the garage so im going to stick to shops with warranty's now. I had a 302 built for a mustang i owned and i blew up around 1500 miles, the rod bearings were almost completely destroyed.

 

how strong is a remanufactured 400? Im thinking of maybe picking one up and starting from there. Would i be able to safely push 400+ HP out of it? Whats the stock compression for a 400?

 

"Stock" compression was about 8.5:1. However, "stock" 400 heads are terrible from a performance standpoint. I had a '70 Impala with a stock 400, I couldn't figure out why going from 2bbl to q-jet and single exhaust to dual didn't help it much. Answer is the heads are terrible (which I didn't learn until after I did some family swapping and my brother had it).

"Stock" rebuild isn't the typical approach from a performance standpoint. Stock had short rods, but 5.7" rods can be used with appropriate pistons, which are readily available. Stock 400 cranks aren't particularly strong, you might want to consider an aftermarket crank.

Check these guys out http://www.rebuilt-auto-engines.com/...45105383085.86 - they don't start the build until they have talked to you about what you're after and what they can do. If you ask for 5.7" rods, aftermarket crank, and better heads, I'm sure they'll accomodate you.

 

Would the lg4 heads, or 416(?) heads which is so common, be any better than the stock 400 heads?

 

They would flow better, especially with 1.94/1.60" valves and porting work. However, you would need to control compression because of their stock 58cc chambers.