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Which 440 would you build?

1Tlew0

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Long story short, I received a call from my engine builder yesterday stating he found a significant crack by one of the frost plugs during the tear down/tanking of the motor. I talked with a family member who repairs blocks, and he said it could be fixed, but I’ve lost confidence in the motor knowing there’s a weak point.

I found a couple candidates for my ‘68 Coronet, but I’m still new to the world of Mopars, so some help, or guidance is appreciated. (I’ve yet to run these past the builder, but will once he calls back). These will all be torn down and gone through.

The goal - A mild build. Cam. Alum Heads (not set on those yet). Intake. Headers (or hp manifolds) Holley Sniper. Etc.

Potential Motors as of right now.

• 1968 440. (apparently it is an HP motor). It lost a bearing, but was still running when pulled. Motor work is unknown, but has a cam and newer timing chain.

• 1967 440. Complete. Been sitting in a heated shop since the 90’s and spins freely. (Casting numbers are somewhat hard to read, but was noted as a ‘67).

• 1968 440. Bare block, with caps. This has some pitting on the cylinder walls and is recommended to go .030 over, possibly .040. It’s currently sitting at another engine builders shop, and has been tanked/shot blasted.

• Keep looking for another option

I have an Edlebrock RPM Performer Intake with the valley pan and gaskets, Mancini Water pump and housing, Mancini oil pan kit that came with the Melling Oil pump, and misc gaskets for a full rebuild. All those parts are brand new. I also have a forged crank, and all the other parts off of my old motor. Which all checked out fine, however, it has a 76 casting date. (I got the forged crank a while back to replace the cast).

Pictures below are of the 1968 and the 1967.

The bare block is not pictured.

What are your thoughts?

440_1 (2).jpg 440_2 (2).jpg 440_3 (2).jpg 440_4 (2).jpg 440_5 (2).jpg 440_6 (2).jpg 440_7 (2).jpg 440_8 (2).jpg
 
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All this depends on the amount of wear and defects found in each. You want the best block that needs the least boring. The more standard the better.
My personal preference would be the 67 engine. If unmolested it's got the best heads IMO. This is the motor I would tear down first and if its good for building, I would go no futher.
 
I agree with Jerry.... and here's my two cents; I applaud your common sense that told you, cracks equal stress, and who wants to put money into a potential issue down the road, repairable or not?? Good on you.
 
All this depends on the amount of wear and defects found in each. You want the best block that needs the least boring. The more standard the better.
My personal preference would be the 67 engine. If unmolested it's got the best heads IMO. This is the motor I would tear down first and if its good for building, I would go no futher.

Thanks. After re-reading what I wrote, it seems pretty obvious that the '67 would be the better candidate.
 
I basically look for an uncracked core, after that I go by how close it is to stock bore. The later blocks had strengthening ribs on the side that are desireable but for a stockish build they aren't important.
 
A '67 440 block is just fine. A later '68 block has the ribs between the freeze plugs, little better? Look at the heads and see what the casting numbers are. A '67 can have several versions of heads. The '68 looks like an early '68 block without the ribs between the freeze plugs, same as a '67.
 
If the cracked block at MS is a numbers matching block to your car, might want to keep it.
 
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The 69 and up blocks had strengthening ribs, but as stated, for a mild build I wouldn't worry about them. The HP and HP2 stamps were just that, stamps, same block.

Mark
 
I would likely to with the 1968 engine. Although it obviously would not have a matching VIN to your car, at least it is a 1968 block, same year as your car. The block would be stamped D440, and have 1968 casting date. It sounds like you have a good steel crank out of your cracked engine and may be using aftermarket heads and intake anyway. In real life, nobody notices these details anyway at the type of car shows and cruise-ins that most of us attend. It is mostly at resale that these concerns crop up. I bought my 1967 R/T without a powertrain, and purchased a 1968 440 with a 727 attached out of a junkyard New Yorker. I had it built to Magnum specs. It has been in the car for over 30 years, and no one has ever made a fuss about having the wrong year motor in my R/T.
 
I agree with others, the 67 block is the way to go. Having said that, I built a 440 25 years ago that had a frost crack above the starter, and it is still running today with no issues. All I did was clean it good and use JB Weld! ruffcut
 
My 69 440 block had a crack that the machine shop repaired/stitched on their recommendation. Engine makes 600hp and I am not concerned at all.

At the time I didnt have many options with blocks so I just had them fix it. If you have options, then maybe put that one in the corner and build another.

I would go with year correct for 1968. If you want max power, build a 512 stroker out of the bare block 0.060" over with trick flow heads, aluminum everything (water pump, intake, etc). Beware that this route is a slippery slope in terms of $$$.

If you want a stocker for cheap, rebuild the complete '68 engine with the bad bearing. Tear it down completely and do stock all-iron rebuild with maybe a hotter cam or something.
 
Stitch the crack and forget about it. It crack is from water freezing in the water jacket not because of stress.
 
I agree with Jerry.... and here's my two cents; I applaud your common sense that told you, cracks equal stress, and who wants to put money into a potential issue down the road, repairable or not?? Good on you.
That crack is from water freezing not from stress.
 
Personally, take the one that had the thickest cylinder walls.
Sonic testing is not that hard. I'd stay away from boring any block larger than needed. The walls can be pretty thin on some blocks because of core shift.
 
That crack is from water freezing not from stress.

I gladly stand by my statement. I don't know what you call the power of ice trying to bend iron, but I guarantee you that the block is no longer stress-relieved after a water damage crack. I'd go with a seasoned block as long as they are still readily available. However, I would not throw it out either... I'd hang onto it in case it becomes a better option for a numbers matching setup if the value comes into play.
 
I gladly stand by my statement. I don't know what you call the power of ice trying to bend iron, but I guarantee you that the block is no longer stress-relieved after a water damage crack. I'd go with a seasoned block as long as they are still readily available. However, I would not throw it out either... I'd hang onto it in case it becomes a better option for a numbers matching setup if the value comes into play.[/QUOTE Cracked block was a 1976 engine, so it will not be matching #.
 
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