440 engine help

[plymouthman]

Ok all.
I am wondering what the differences are between the 69 440 and the 77 440.
I've found that the stock 69 had 10.1 compression and the stock 77 had 8.1. What's the difference. Heads ? Pistons ?
I don't see the blocks really being different. I have a well used 69 complete engine but am getting ready to go pick up a complete 77 440. Why is the hp and compression so different.

 

[Xp29h]

I'm curious what the two motors came out of. The 77 came from a Motor home maybe?? Where heads would be different, pistons and lower compression. Im also thinking that piston distance below the deck is closer on the lower compression motor. I may be way off. I'm sure others with much more knowledge will jump in here!

 

[miller]

Many of the other guys can go deeper into the differences for you.

But, in a nutshell, yes on the heads, pistons, cam, so on, that make the compression differences.

Suggest going to the 440 source website...at the data section. It shows the (if any) differences on blocks, heads, and such.

I've always considered a 77 motor a smog motor. (Probably get slammed for that one.) But between the two, like the different heads, and some of the internal parts, is what makes the dif. Otherwise, some of the parts, such as rockers and shaft will easily swap. The 69 'could' have some of the more desirable parts, depending on what your after.

 

[plymouthman]

Not sure what the 69 came out of but the 77 is coming out of a new yorker with 55k original miles.

 

[terzmo]

Currently have a 78 block in my 67 R/T with the 452 heads. Came with the car 4 seasons ago and from the sound and performance,a healthy cam at the least was done. I believe in it's current condition,it would outrun a stock 67 R/T motor. I'm building a hemi for the car and that 440 motor will be available. Some claim the mid 70's blocks are stronger than the 60's....how they know is anyones guess. Good luck.

 

[NitroNeal]

Not sure what the 69 came out of but the 77 is coming out of a new yorker with 55k original miles.

Yes the blocks are different. The thrust bearing is different diameter. The mid - late 70's were also known as "thin wall". They usually won't take as much overbore.

 

[IQ52]

Ok all. Why is the hp and compression so different.

Two main reasons, camshaft and pistons. Much rumor and speculation posted above with some truth.

 

[plymouthman]

I've read somewhere that the pistons sit lower in the bore. If that's correct, I'm assuming the pistons are shorter in the later blocks so I'm considering using the 69s bottom end. Pistons, rods, crank. I shouldn't have any problems with that correct. No machine work needed other than to the crank correct

 

[IQ52]

What machine work are you contemplating to the crank?

 

[plymouthman]

Polish or turn if needed

 

[plymouthman]

I am looking to keep it stock bore size but want the 10 to1 compression of the earlier engines. Am I correct in thinking that the 69 bottom end will go right into the 77 with no machine work ? Unless the crank needs polishing or turning.

 

[Badvert65]

You will need to get main bearings to fit the block (thrust bearings are different), other than that everything will swap easily. If the pistons are in good shape from the earlier engine, I would use them. You can run 10:1 compression on the street, especially if you have a high overlap cam. I have been running a 440 with 10.4:1 compression for years on pump gas. Easier to set timing if it runs a little on the rich side but easily doable. I also ran a 75 440 that was completely stock (cam and all) in a 72 Dodge pickup. That motor was just awesome and I believe it was only around 8:1 compression. It is really hard to go wrong with a 440. That's why I love them.

 

[plymouthman]

My original plan was to bore the 69 block .060 over , flat top pistons , 509 cam , 915s ported and polished, Offenhauser single 4 tunnel ram , 750 holley race carb , Hooker headers.
But then the funds kinda slimmed down and I just got one heck of deal on the 77 440 with 55k on it .
I want the compression and the 77 440s don't have any , even with the 915s. Only looking at like 9 to1. So that's why i got ta thinking about the rods and pistons from the 69 over to the 77.

 

[miller]

The 69 block is the better choice, considering the dif between the two. .060+ bore??? Why? Or are you just looking at the bore size numbers?
What's the bore size on the 69 as it is? Anyway...punch it all you want, it's in your hands.

Good chance the 77 motor has a cast crank in it. No telling on the 69. Without a hit, or number, to tell steel or cast. Of course, the forged steel crank is better, depending on the wear on the journals. Rods in the 69 could be better, depending on what number.

915 heads? If you've got 'em, go for it. 69 will have 906s...77 probably 452s.

All adds up to the numbers you figure on, and the package you put together. Real easy to bolt together gobs of HP, or a boat anchor. THAT's what so great about 440s. Simply depends on what you shove into it, and how you do it.

Have fun!

 

[plymouthman]

The reason for the possible bore was to make 451ci,
And i have a set of .060 pistons just sitting on the shelf and is not really in the budget to buy new pistons. So it's hopefully use the original stock 69 pistons or bore the block to.060 over if the 69 block needed bored to clean up.
Now that i have the 77 engine with only 55k on it , I don't see why that would need bored at all. So stock pistons should work. The 69s pistons are taller from what I've read so it would bring the compression back up to what it was in 69 around 10 to 1.

 

[HT413]

Sounds like a good plan to me. According to 440source website, later blocks are not thin wall, that's a myth. They are technically a better block due to thicker webbing in the mains plus more support webs around the skirt. Not that means anything to someone like you or me who aren't looking to push the horsepower limits of the block.

Before going through the hassle of swapping rotating assemblies, have you measured the pistons those 69 pistons to be sure they are what you think they are?

 

[miller]

Don't remember what year the change was, but also different thrust face diameters for #3 main journal on the blocks. Something to at least check out.

 

[plymouthman]

No, I haven't cracked the 69 open yet. It's a stock all factory block and from what all I've read on those engines they all came with from 10 to1 up to 10.3 to1. I did see an arrival from hot rod where the built the exact same engine I'm wanting to build. Except they only swapped the 69 pistons nothing else. Just new bearings.
And your right, I'm not pushing the block to its max. Would love to say I have the $ to afford too but reality sets in and crushes that idea

 

[plymouthman]

That article I referred to is , mopar muscle. Hot rod network ( 440 mopar engine - back to basics) dated April 1, 2013

 

[Seax440Dodge]

As stated above, the heads, cam, thrust bearing are slightly different, but the main difference on compression is the pistons.. they'll be about .100 down in the hole, and have a big dish on top of that.. the chambers on the heads should pretty much have the same (88-ish) cc as the 69 but with induction hardened valve seats.. should have same sized valves as the '69 (2.08, 1.74)

I've punched the cylinders out on these 'thin wall' late 70's castings over and over again, they sonic check just the same as the 60's blocks.. IMO the thin wall thing is a myth..

The main saddles and support webbing is beefier on the late blocks and the cooling passages are a little different, if I were you, I'd use the late block w/ the early block's rotating assembly