Questions about the Mopar Performance 340 Replacement Block P5007552AB

[69_340_GTS]

Thinking about building an all-new motor for the '69 Dart. This 340 Replacement Block P5007552AB looks like a good place to start. Couple questions though:

1) Is it actually bored/honed to 4.040", or will it need machining? One place I read says it comes rough bored only.

2) Will the 90° oil filter adapter off the old 340 fit on this block? I ask because I have read that this block requires a "special" filter p/n 05281090.

3) Will I really need to drill oil drain holes in the lifter valley?

4) In the "Big Inch Mopar Small Blocks" book, they have this statement, which is extremely confusing: "340 replacement blocks have stock 318 LA-style motor mounts, so they can be used in any vehicle that was originally equipped with an LA small-block engine. The left-side 318 LA motor mount on this block is different from that on a stock 340/360 block. A mid-1970s 318 left-side motor mount must be used when installing this engine/block in a vehicle that was originally equipped with a 340 or 360 LA engine".... So will it or will it not drop into a '69 Dart that came with a 340? If not, what is the P/N of the motor mount I'll need?

Thanks! I know someone here can answer these questions!

 

[dragondan64]

The block has a few cosmetic differences from the original 340 Block, but it is machined to work with all 340 production components. Special features include brand-new castings made from high nickel cast iron for added strength (not a thin wall casting), 4-bolt main bearing caps, and 340 journal size. It has thicker webbing and pan rail (like the 1970 340 T/A version), a thicker deck surface and thicker bore walls in major and minor thrust directions. Block is rough bored at 3.900" to allow various bore sizes, from 3.910" to 4.080" (finish bore and honing required). Deck height is approximately 9.600".

 

[69_340_GTS]

The block has a few cosmetic differences from the original 340 Block, but it is machined to work with all 340 production components. Special features include brand-new castings made from high nickel cast iron for added strength (not a thin wall casting), 4-bolt main bearing caps, and 340 journal size. It has thicker webbing and pan rail (like the 1970 340 T/A version), a thicker deck surface and thicker bore walls in major and minor thrust directions. Block is rough bored at 3.900" to allow various bore sizes, from 3.910" to 4.080" (finish bore and honing required). Deck height is approximately 9.600".

Yeah, but you just copied that from that "Big Inch..." book, I think. If you look at the Jegs listing for P5007552AB they say it is already bored/honed to 4.040" which is the finished size for a 340 piston. See why I am asking questions?

 

[dragondan64]

Yeah but doesn't this say all production 340 parts fit? and no the blocks are rough bored and you need to have it finished to match whatever pistons you want to use. I think you can actually order different rough bore sizes too. Here is a new listing here at FABO for 340 short block for 650 bucks.

http://www.forabodiesonly.com/mopar/showthread.php?t=295718

Just read this build using the block you are asking about has the required machine work needed and sounds extensive to me but good read for you. Hope this helps.
http://www.hotrod.com/cars/project-...-valiant-project-70-small-block-engine-build/

 

[69_340_GTS]

The Hot Rod article states "...ordered from Mancini was part number P5007552AB. It was delivered to us finished honed at 4.040-inch bore size, and came complete with..."
LOL, see why I have questions!

 

[69_340_GTS]

So, nobody has any first hand experience with this block? I find that hard to believe!

 

[replicaracer43]

Its a little pricy for most of us, the purchase price and then the machine work together....Used 340 blocks still are not totally impossible to find, and can be cheaper. That's probally why not many have used them

 

[69_340_GTS]

It doesn't sound like you have to do any machine work to use it. All the stuff they did to that block in the Hot Rod article was not necessary, really. At least that's how I understood the article. I think the only major question I have left is what is a a mid-1970s 318 left-side motor mount? Any idea where I could get one and what the part number might be?
http://www.hotrod.com/cars/project-vehicles/mopp-1010-1968-plymouth-valiant-project-70-small-block-engine-build/

 

[MRL Performance]

If you believe any block you find from MOPAR isn't going to need any work at all to use and BE RIGHT, your living in another world. I had to machine a $3000 block so much, even make room for counterweights(as they were not done from the factory), that it almost cost $5000 when done. I don't think I will ever use one again unless I have to.

No company will ever make a nice affordable block for Mopars, ever. Its a shame. If engine builders like myself could get a NICE block, machined accurately, with all the fixes made right into them that we have to fix all the time for $1700, we would jump all over them, like the Dart blocks for SBC. But it will never happen.

 

[moe7404]

in the past i have seen NEW bare blocks from chrysler come with NO block to trans lineament dowels. with out them the converter flex plate will NOT last. if you you have access to good tooling dowels a 1/2 should work and you can make them a little longer than stock.

 

[moper]

If you believe any block you find from MOPAR isn't going to need any work at all to use and BE RIGHT, your living in another world. I had to machine a $3000 block so much, even make room for counterweights(as they were not done from the factory), that it almost cost $5000 when done. I don't think I will ever use one again unless I have to.

^ this.
No blocks currently available in big block or small block should be expected to be able to be used as delivered with the exception of Keith Black's. And the KBs you need to carefully check everything just to make sure - everybody's human and there have been issues found with those too. The MP stuff plain sucks. Plan to re-machine it completely, and make sure the shop can check the alignment of the lifter bores.

 

[Otto Mobilia]

sub'd

 

[69_340_GTS]

^ this.
No blocks currently available in big block or small block should be expected to be able to be used as delivered with the exception of Keith Black's. And the KBs you need to carefully check everything just to make sure - everybody's human and there have been issues found with those too. The MP stuff plain sucks. Plan to re-machine it completely, and make sure the shop can check the alignment of the lifter bores.

Anything in particular?

 

[moper]

Anything complicated... They've been producing crap for castings for years. Nevermind the ECUs and camshafts. Porous W5s, Stage heads with machine work done by monkeys, big blocks & Hemi blocks that can't go beyond factory bore because they're so thin. Same monkeys doing the block machining. Do some research. You can find issues galore. I've personally had to deal with thin blocks and W5s that needed a ton of work and sealing to get usable. It's unfortunate but you really need to be careful when buying and it's besst IMO to buy from someone like Shady Dell who has intimate knowledge of the quirks and knows how to make sure what you have will work for you.

 

[tubtar]

in the past i have seen NEW bare blocks from chrysler come with NO block to trans lineament dowels. with out them the converter flex plate will NOT last. if you you have access to good tooling dowels a 1/2 should work and you can make them a little longer than stock.

And make sure you measure the i.d of the hole.
You may need to ream the hole for them with a .499 reamer so you only use a .001 press fit..........or risk cracking the ear on the bottom of the block.

 

[A body]

If that block were the siamese one it would have been gone a long time ago.... Warren MI shows "1" in stock..... that would be the last as they are not making them anymore. You want it, you best pull the trigger!