MP Short Block Autopsy

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FASTBACK340

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Well I finally got around to disassembling my short block this week. For those of you whom are from the old board will remember my post on this topic a while ago. For the new guys here's a brief run down:

I bought a Mopar Performance 9.5:1 short block for my `68 Barracuda. The biggest concern everyone had was to open it up to check clearances and clean it up. The clearance look good (so far...) as I need to borrow an inside micrometer. As for cleaning it.... all I can is you must be %$#@#$% CRAZY to drop one of these things into your car without a THOROUGH cleaning! I found everything from cardboard to dust bunnies living inside it! :shock: I stripped it down, hot tanked it at work, then proceeded to grind out all the oil drains in the lifter galleries and clean & re-tap all the bolt holes. For those of you whom have never done this let me say that getting your weiner caught in your zipper is more fun..... After about 2 hours of grinding and smoothing I tanked it again, followed by a thorough cleaning with detergent & a set of block brushes in all the oil galleries and water passages. A DIY root canal was more appealing at this point.... But I pressed on. Well, all my work paid off as I now have a SPOTLESS block awaiting a fresh coat of paint and re-assembly to follow. Pictures will be posted ( hopefully tomorrow)

Then I finished up my day by picking up my freshly done X heads from the machine shop. 3 angle valve job, guides cut for Teflon seals and double valve springs, and a mill job. Beautiful work as done by S&K Speed out here on Long Island!

The only bad thing I've spotted so far is a slightly mis-aligned #2 cam bearing where the oil hole is not centered properly. I've been mulling over what to do. At the moment I'm inclined to open up the hole a bit since it's not off *too*far. Otherwise, I'm pleased.

More gory details to follow. Stay tuned kiddies :wink:
 
I've always thought you HAD to replace cam bearings on a engine thats been 'tanked. You've 'tanked yours twice?

Just wait till you get that bad boy back together and in the car. You'll forget about all the 'unpleasant' work that went into it. :)
 
I've always thought you HAD to replace cam bearings on a engine thats been 'tanked.
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Hmmmm...... Maybe I didn't fully explain what I meant by "Tanked". At my shop we have a high pressure degreaser tank that we throw engine parts into to clean them up. I ran my block through twice. As far as I know, the tank isn't filled with anything too vile. The block came out with paint still on it.... but CLEAN!

I hope this doesn't nessitate pulling the cam bearings, even thought one is not *perfectly* installed :wink:

Thanks for the feedback. Good to know people are reading posts :D
 
Well Im glad you checked it out. Ive been thinking about the 380 horse crate motor. Wonder how they are ?
 
fastbackcuda said:
Well Im glad you checked it out. Ive been thinking about the 380 horse crate motor. Wonder how they are ?
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My guess would be all the crap would be bolted up inside the motor :?

A buddy of mine, who's bolted together a few hi-po motors in his day, commented on the nice job they did on mine. Except for the dirt, the machine work and parts look very good (for the money....)

Like the old saying goes, you get what you pay for. This particular block looks to be a notch or two above that generalization.

I just hope the sunofabitch runs good :twisted:
 
Im sure it will run good when its together.

The magnum crate motors are all new castings.
The short blocks are all remans So the Mags may be abit cleaner.
 
sounds better than you thought did you plastigauge the bearing and check the crank? I am asumming that they used stock rods and pistons? On those cam bearings as long you didnt use any of that Citric solvent that eats bearing you should be good. joe uses that **** in his hot tank and it will eat any soft metal if left in for a long time.

Cant believe all the crap that was in it. Thats just a case of someone not giving a crap. if you got it that far though it should run like hell :shock:
 
Hmmmm...... Maybe I didn't fully explain what I meant by "Tanked".
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I knew what you meant. But every engine building book I've read says to change the cam bearings after hot tanking. It may be dependant on the chemicals used. :?:
 
chad72duster said:
with the flowed Xhead should run pretty good. What intake and spark are you going to use?
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I'm using a six barrel set-up with new carbs and a K&N filter. The spark is one of those Accell super coils and a stock electronic distributor. I'm planing on upgrading to a high performance distributor (suggestions?) and a MSD soft-touch rev limiter. It has the .509" MP cam. I'm hoping the sucker pulls 325-350 HP.

We'll see!
 
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