Im replacing the flat 6 in my 53 Mopar and would really like to do a big block B-R/B engine in it, especially a 440. Based on what Ive been told (and also on what Chrysler says in my Big Block B-R/B Engines book published by Chrysler) the mid to late 1970s 440 engines (and 400 engines) are thinwall and can only be overbored .020. I dont plan to overbore anymore than what is necessary but in wrecking yards its hard to tell if the engine has been done over or not especially on an engine thats been out of production for almost thirty years. Ive avoided any of the thinwall big blocks because if it needs .030 to bring it back Im screwed since all purchases are final. That makes it much harder to find something (mostly what I find anyway are 360s and 318s). Anyway, I came upon this info on the net which essentially says there are no thinwall big block Mopar engines. Can this be really true ??? Here are the websites: www.440source.com/blockinfo www.arengineering.com/articles/sonicbig02 Although Im not fond of externally balanced engines (limits damper and torqueconverter swapping), if this info is true it opens up a bunch of cars/engines I have been avoiding. Since you never know about web information, I wanted to see what HAMBers have to say since I trust your opinions! Thanks!!!
I don't know - what I do knwo is back in school my buddy had his '69 440 GTX bored .090" over - thing ran like stink too!!! It was FAST.
yea its true. mopar action did a story about this very subject years ago. they proved with an ultrasonic measuring device that most late 60' on up blocks were just fine. in fact the cores they checked as possibly being weak were those of the earlier motors, if i recall right. they did say to stay away from blocks that were cast with numerous cores. you can check this as being the very last digit in the block casting number. the higher the number the more cores they had to use in order to get the correct spacing on the cylinder wall castings. so the lower the number the better. 0-1-2 very good, 3-4 pretty good, 5 was good for stockish types, any more than 6 keep looking. the same holds true for small blocks.
There have been many articles written on this debate. Actually the best article and testing done is from a book by Chuck Senatore, called Big Block Mopar Performance. Good all around book covering build stuff, and different tips. Check it out here: http://www.amazon.ca/exec/obidos/ASIN/1557883025/701-4206010-4353963 Another good book I've found regarding build and background info is: http://www.amazon.ca/exec/obidos/ASIN/1557881901/701-4206010-4353963 There have been many reputable persons to say that the thinwall block idea is a myth and based on articles I would agree. I have never done testing myself so I can't say from experience just from what I have read. If you have a block within question, I would just Sonic test it, but I would do that when any big overbore is required. etc. I think like many "commn beliefs" are true for some, yet another person can come along and do exactly the opposite and be fine forever. As always...Just my opinions
I had a '78 .030 over 440 in a '68 Charger, never gave me any trouble. The problem with the later 440s is they switched over to an externally balanced, non-forged crank. Bleh. Replace it with a good forged one at the time of rebuild, and you're golden.
I had a 69 440 block bored .060 .. ran 1 zillion runs on it in my 1964 drag car made 586 hp on the dyno, never ever broke a piece on it motor was built in 1989, ran it till 1996 , took it apart, not one piece was broke or over worn cleaned it all up and sold it so I COULD build my next one , this one is just a tad more motor, (check photo)
Want to say Thanks y'all for your responses, I really appreciate it. Looks like I can check out all the 440's I can find now. I agree the cast crank/external balance deal sucks on the later motors but that's why God gave us tools. I can deal with that in a rebuild and have something haelthy when I'm done. Loved that thumbnail of the BIG R/B!!! Should make the rat motors quiver a little when it comes around! I knew fellow HAMBers could give me some direction.........Thanks again!
Check out the motor homes too: a lot (most?) of them have 440s in them. ~ Paul aka "Tha Driver" If guns cause crime, all of mine are defective.
I would look at buying a whole car, subbing a 318 (since those are as common as opinions on here), and selling it on. Usually, a whole car is cheaper than just an engine. FWIW, a few years ago I was swimming in Chevy TH400's, because I had been collecting vans for parts, and all vans came with TH400's. Most were free to $50.00. Cosmo
if you are looking for anything Mopar .. www.moparts.com There should be people very close to you where ever you are with what you need .. Mopar people help each other like no other
I had a '75 truck block that was .060, it ran fine and didn't split a cylinder. I pulled down a factory reman for a guy to "check it out" that came out of a later '70s truck that had .030 slugs in it. It needed a valve grind to make it a driver. Could it just be that MOPAR is in the business of selling parts?
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