Strange 318 Block

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@mchartier105
Manitoba here as well.
That block may seem to you as worthless,but i wouldnt scrap it.
Good blocks are getting tough to find.
 
Really enjoying this thread on the 318 Blocks and 318 X Race Blocks.

Here is some more good info on the X Blocks from BigBlockDart.com:

jyrki:
Re: 318 X block
It was the old direct connection race block, offered years before the currently unavailable R-blocks were available. It was delivered with a 3.91" rough bore, and could be bored up to 4.10" without much problem. It was a beefier casting, the weak areas of the factory blocks had been fixed, and the main webs were extra thick and accepted four bolt caps. Some were delivered as two bolts, and some four. It's a good base for a powerful LA engine, that unlike the later R-blocks accept roller lifters etc just like the stock factory blocks.

(abodyjoe 2008)
Re: 318 X block
A good X-block is worth about $1200 maybe more. should have a big X cast on the front of it and the dipstick hole wasn't originally drilled out.

DJV Cuda 2008:
Mine is about 25#'s heavier then standard LA block.
(this I wanted to know, George Jets)

Like stated 3.91 rough bore supposedly can be taken out to 4.125
the deck is thicker, the nickel content is higher than standard blocks, and the main caps are stronger, i forget what they are made of but they are stronger.

The blocks were used in Pro Stock until the late 70's early 80's, mine is a 79 casting.

Scamp408:
Re: 318 X block
X in front and back
All weak areas beefed up. blocks were also used in Nascar late 70s and Iroc in 90s.

jyrki:
They sold the block bare with the rough bore only. Bore it, install stock oversize pistons, and other stock 318 internals & externals, and you have a stock 318. The fact that and engine has got that block doesn't necessarily mean it will be huge in power, but that block is a very good foundation for a powerful LA engine.

scamp408:
Re: 318 X block
If there is no X its not an X block. They used a 318 casting # on the X because they need the 318/340 main bore.They didn't have 340s anymore so it could not be a 340 #. The X means it's a race block, big diff in how it was made: Cast Iron mix, wall thickness, main web thickness, deck thickness, all weak points were addressed.
 
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@mchartier105
Manitoba here as well.
That block may seem to you as worthless,but i wouldnt scrap it.
Good blocks are getting tough to find.

For Sure, can take a plastic garbage can and put in 10 gallons of 6% cleaning Vinegar, let the block down in with your cherry picker (as you have it nice and clean and de-greased already) until submerged, let soak overnight, pressure wash out the cooling jacket and block, rinse it off with distilled water and scrub it down with a scotch brite pad and some WD-40. Will look brand new and the WD-40 helps keep the rust back until you get time to build it. Cylinder bores can be lightly honed clean too after the rust is neutralized with the vinegar.

Did the same thing with a lightly rusted 360 Crank, made a fiberglass box the size of the crank. 4 gallons of 6% cleaning Vinegar, let soak overnight, rinse with distilled water, scrub with scotch brite pad and WD-40, polished up the journals with Crocus Cloth, Brand New !

This was a recently cut .010"/.010" crank, so yes sweet deal.
 
Kinda off topic but I recently came across an aluminum 318 magnum block forsale. $5k.
Supposed to be one of four. I believe it’s just the block for $5k. Has 4 bolt mains

EC233D9D-43B8-4E5C-9283-AE0FB0594CE3.jpeg
 
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As long as the subject of desirable strong 318 engines blocks is up, here is a comparison of three 318 blocks.

First up: The 318 X Block, Racing Block, 25 lbs heavier that the standard production cast block.
With the solid fill mains webs and extra beef in the weak areas of a production block.

Second Up: 1969 318 Factory 230 HP, 9.2:1 Compression, with the solid filled mains webs. Has one of the Best Cast mixes, cast in the muscle car era of 69.

Third Up: 1979 318 standard production engine, with the lighter duty undercut mains webs.
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First Up: 318 X Block, Racing Block

318 X Block.jpeg



Second Up: 1969 318 Factory Production 230 HP, 9.2:1 Compression Engine Block
Good Strong mains webs. (also notice it came with a forged crankshaft)

69 318 230hp.jpg



Third Up: 1979 318 standard production engine, light duty block with recessed mains webs.

79 318 Block.jpeg


Good look at a few blocks here.

Availability: The X Race Blocks are all but gone, 69 318 230 HP Blocks strong and still in the 69 cars that are up for sale yet, and some are on the shelves of the Mopar folks hanging on to wanted parts. 79 318 production block still available from used vehicles.

My personal preference is the 1969 318 230 HP Block, plenty strong for the street class of cars we are building, not an over kill, 20 lbs lighter than the X and they are still available yet.
Notice I said Yet !
 
As long as the subject of desirable strong 318 engines blocks is up, here is a comparison of three 318 blocks.

First up: The 318 X Block, Racing Block, 25 lbs heavier that the standard production cast block.
With the solid fill mains webs and extra beef in the weak areas of a production block.

Second Up: 1969 318 Factory 230 HP, 9.2:1 Compression, with the solid filled mains webs. Has one of the Best Cast mixes, cast in the muscle car era of 69.

Third Up: 1979 318 standard production engine, with the lighter duty undercut mains webs.
-------------------------------------------------------------------------------------------------------------------------------

First Up: 318 X Block, Racing Block

View attachment 1715320225


Second Up: 1969 318 Factory Production 230 HP, 9.2:1 Compression Engine Block
Good Strong mains webs. (also notice it came with a forged crankshaft)

View attachment 1715320228


Third Up: 1979 318 standard production engine, light duty block with recessed mains webs.

View attachment 1715320230

Good look at a few blocks here.

Availability: The X Race Blocks are all but gone, 69 318 230 HP Blocks strong and still in the 69 cars that are up for sale yet, and some are on the shelves of the Mopar folks hanging on to wanted parts. 79 318 production block still available from used vehicles.

My personal preference is the 1969 318 230 HP Block, plenty strong for the street class of cars we are building, not an over kill, 20 lbs lighter than the X and they are still available yet.
Notice I said Yet !


There was ONLY ONE and ONE ONLY production block with a filled pan rail. That was the T/A block. There was never ever ever a production 318 block with a filled pan rail. Ever.

The X block was sent out with the rough bore of 3.91 (which is actually more like 3.800ish at best) and was given a 318 part number so the stock eliminator guys could use it.

Even Ray Charles can see in the second picture you posted that 318 doesn't have a filled pan rail. That dude is not only blind, he's dead and he can see it.

This **** isn't hard. The order is: T/A block, then the X block and then the R series. There are no magic production blocks. One is no better than the other.
 
Did not say the pan rail was filled, the webbing only is filled thats why it's 20 lbs lighter.
69 318, and yes it is pretty obvious.
 
68-73 318 are the ones I use.
They are slightly stronger at the main webs, "even Ray Charles can see that, and he's blind" They also seem to be candidates for a 4"-4.04" over bore.

4 ear mounts, here nor there, still stronger in that depot.

I like the idea of measuring between the cylinder cores through a freeze plug hole of a later versus early 318... that's interesting to me and should enlighten the rest who don't know 1st hand or believe.
 
I recently ran across this great discussion because in searching, I found that I have the same type of block that I thought I was going to use for a build but now will not use because of cracks on the deck water jacket. I noticed that there was a lot of talk about the bottom end of this block but really nothing about the top deck. I thought it would worthwhile to mention that the deck on the 1980 "R" 318 block is significantly different then the 1969 318 block I took out of the car. The 1980 "R" 318 block has many more water jacket openings. My "R" block has 6 cracks between the head bold threads and the water jacket (look between the pencil markings in the picture). I assume someone at one time over torqued the head bold significant enough to crack the block deck. Or it had water in it and if froze. Beware of these "R" blocks.

IMG_6320(1).jpg


IMG_6321.jpg


IMG_6324.jpg


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IMG_6425(1).jpg
 
I recently ran across this great discussion because in searching, I found that I have the same type of block that I thought I was going to use for a build but now will not use because of cracks on the deck water jacket. I noticed that there was a lot of talk about the bottom end of this block but really nothing about the top deck. I thought it would worthwhile to mention that the deck on the 1980 "R" 318 block is significantly different then the 1969 318 block I took out of the car. The 1980 "R" 318 block has many more water jacket openings. My "R" block has 6 cracks between the head bold threads and the water jacket (look between the pencil markings in the picture). I assume someone at one time over torqued the head bold significant enough to crack the block deck. Or it had water in it and if froze. Beware of these "R" blocks.

View attachment 1716225484

View attachment 1716225485

View attachment 1716225486

View attachment 1716225487

View attachment 1716225488

i think Uncle Tony could weld them cracks for you .
 
I am betting it is a High Nickel content in the block cast mix. The chevy 350 guys want the 010 block that has the high nickel content for their performance builds. I honed one of these and the Cylinder Walls are really really hard.

A good simple test might be to see if it has very little ridge in the cylinders at the top compared to a regular 318 cast block that usually gets a pretty good ridge at the top of the cylinder after a lot of miles.

Will be interested to hear what you find out more on it. Pretty Unique !

All Chrysler blocks are made from the same iron. The race blocks use the same iron as passenger car blocks.

Second, I don’t know what that R means but by the looks of it the pan rail is not filled.

If it’s not filled it’s a run of the mill 318. Post some pictures of the main bearing bulkheads. That’s the quickest way to figure it out.
 
Think it's just a good race block mopar puts on their parts shelf, kind of like the warranty blocks with the blank VIN stamping area.

Mopar had them on the shelf ready to go when someone needed one. I have a Warranty Block that came out of a 76 D-200 4x4 low miles, like no ridge. Got that one up and running now sitting in my 76 D100 Build soon to be on the road.

One check see if it has any vin numbers on the lower right front of the block and go from there.


Wrong
 
Just Great ! I would bet you Lunch that it is the High Nickel 2 bolt main race block. 318 blocks are built tough to begin with, ever compared one to a 289 ford block. The ford block looks like a toy and cracks between the compression side of the cylinder and the water jacket, pretty much junk after that.

Good 318 Block and add a little more nickel to the cast mix and you got a tough one. Always enjoy retracing the mopar engineers footsteps, those guys could hardly wait to get to work in the morning to continue building the mopars.

You’ll lose that bet because you are talking out of your hat.
 
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