What year castings were considered thin walled 440's?  Can thin walled castings be bored anything over .020-in?  

I thing the 72-78 were what they call thin wall blocks. It depends on the block how much you can bore it but they can go .040" with no problem after that they should sonic checked to see how much more can be taken off. Alot of them can go .060"but you should always have them checked before going that far.  

there was a mopar article a few years ago,thay sonic tested like 10 blocks,pre70,70n up,motorhome,thay all came to .120/130 wall thickness.i think thay said .060 over was fine unless you put out 800hp then the wall might flex and to use hardblock halfway up water passage to cure.have you heard of this?

Cvon,

As it turns out, there was no such thing as the "thinwall" 440's, it was, and is kinda like an old wives tale. Before you do anything, go to this link and read the whole article, you'll be amazed! Let me know what you think. Good luck!!

http://www.arengineering.com/articles/sonicbig02

............Robert  

A friend of mine used some stuff called Steelcrete in a Hemi and it was bored .080" and running over 800Hp, all was good until he broke a piston.  

Hay that was a some good stuff, I never doughted my 78 440s or my 77 400. They have not let me down yet!  

235lbs RB,I thaught it was heavy when i lifted it up on the engin stand while my squeez held the stand steady.I cant have a lift in the basement too!I get it up and down the basement steps with a dolley.  

Goatheat,

Yes, they were and always will be great engines. So over-engineered and nearly indestructable even the so called "Thinwalled" are massively strong. Pound for pound, dollar for dollar the best and most powerfull engines made. Yea, I learned a lot from that article too. Have fun!!!

................Robert  

Warlock,

Great article!  The facts of this articles findings prove that we've all been mislead.  This makes me feel better, I've come across a 440 for sale but was hesitant about getting it simply because I was unsure what year the seller had, but after reading this,  I'd be silly to pass up this deal because of the casting year. Whether soft or hard material casting, I've got to remember I'm not going to race this car in NASCAR.  Thanks for the Info!  That's why I love this message board!

Cvon,

   

   No problem, my pleasure. I'm glad I could help!!

....................Robert  

the lnk doesnt work anymore..could someone describe what it said about the blocks? doesnt have to be a whole books worth of detail just a rundown would be appreciated  

74 and later were considered thin wall but are still capable of .030 overbores if not building 12.5 to 1 compression or larger motors.  

Actually there were no "thin walled castings". but 74 and later the hardness of the iron was a bit softer. Check out the "Sonic checking your big block" article on this link.
http://www.arengineering.com/articles/articleframe.html

440 source has good info too.
http://www.440source.com/blockinfo.htm