Every once in a while, you run into a setback in a car project. While Dan was measuring the deck heights at various points on my 1983 318 block, he determined that the measurements suggested that the block had a bit of a twist to it. In addition, Dan informed me that some of the main saddles were out of spec, and needed an align bore. But, the biggest downer (for me), was his discovery of hairline cracks running from the head bolt holes to the coolant holes. Dan let me know that he's seen this problem before on the newer ('80s/up) 318/360 engine blocks, and he has a method of fixing them. After mentally digesting this unfortunate discovery, as well as the other issues found with the block, I decided to not invest any more into a questionable block, and instead search for a more suitable, older 318 block. As luck would have it, a friend of mine that lives in my neighborhood had just acquired a complete, unmolested 318 engine, of 1970 vintage. I purchased the bare block from him, and I'm going to make preparations to ship the block to Dan within 2 weeks.
Here are two pics of some of the cracks around the head bolt holes that were found by Dan.

Looks great! Too bad on the cracked block.

Don't forget to get oil thru pushrods as the magnum heads oil thru lifters. I got mine custom made from straighline perfoemance.

Good decision

Here is the replacement 318 block I'm sending to Dan. Granted, not as exciting to look at as a blown Hemi, but it keeps me in the Mopar hobby, at least. She was cast back in the good old days of 1970, when an extra pound or so of cast iron on a block was looked at as providing additional strength and a margin for design error, rather than a weight penalty. The head bolt holes are blind, rather than going through into the water jacket, like the later 318 blocks do. Blind holes generally equal more strength, which is why the old blocks don't suffer the cracking problem around these holes.

Bummer, at least you found out before too much was dumped into it.

Probably an elementary question but what years come with magnum heads?

hey Dave, could you resize that picture so we don't have to scroll back and forth.
other than that, i just couldn't take it any more. engines need to start out nice and clean, so here's what it looks like now.

another view

no more scale in the water jackets.

Purdy!

Do you use the Shake n bake method? The machine shop I use has that system and the part can be horrible when it goes in and spotless like that block when it comes out.

Alright guys, Dan is trying to pull a fast one here!! Its obvious that he rattle-canned that block with Eastwood's cast iron gray paint, and painted the main caps silver for artistic contrast! Who's fooling who here??!!!
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Seriously, Dan, I'm in SHOCK!!!
Thanks for posting those pics! When you said you can make the block look like new, you weren't kidding! The last time that block was cleaner than that was when it was cast 41 years, 51 weeks ago today!! Just amazing!! YOU DA' MAN, DAN!!

I performed some surgery on the 727 4x4 trans. The tall mount on it forced me to fab a 1.25" drop section in the trans skid plate. Even with that, there was no room to put some rubber isolators under it. So, I manned up and broke out the Sawzall, and chopped 2.75" off of it, and had a local welding shop weld a 3/4" thick 6061-T6 plate on it. Now, I can take out the drop section and weld in a flat plate to restore the lost ground clearance, and have room to stuff 3/4" thick rubber isolators under the mount.
I'll get this Jeep done someday.

I forgot to take a "before" pic. Pretend you don't see the cut.



The Sawzall blade wandered a bit. A little grinding leveled it out.

That outta hold it.

Things are moving right along. In addition to Dan at Performance Only working on my engine, yesterday I dropped off the 727 at LIP Performance for a complete rebuild, using CRT's HP street rebuild kit and Cope's Pro Street manual valve body.
My NP231 transfer case came with a 3 pinion planetary, which is load rated at 600 ft. lbs. of torque. That isn't going to cut it living behind Dan's little torque monster, so I located a barely used 6 pinion planetary in super condition, and a long style 23 spline input gear, which is needed so it can mate properly to the 727's output shaft. The 6 pinion planetary is load rated at 1,400 ft. lbs. Once I get the wide chain kit, I'll reassemble the t-case.

Dave,
here's a few more progress pictures for you. after checking the main bores out for size and alignment, i decided it needed to be corrected. no big surprise on that since the block is 40 years old.
i start out by surfacing the bottom of the block. the main reason for that is because the main caps hang over the edge and it's either file all of the caps or surface the block. i chose the latter.
after the block is surfaced, the caps are off to the cap grinder to remove a few thousandths of material. and of course finally, the CNC bores the holes round and true from front to rear. the variance in size afterward is .0001 max. the before numbers would scare you, so no need to go there.

and another

Awesome, I am curious about something to do with line boring if I may ask. Doesn't it changer the distance between the crank center and the cam center? How do you conpensate for that or is it so insignificant that you would never see an issue with timing chain slack.

Thanks, Kevin

here it is with the caps bolted down before boring