340 crankshaft info needed

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Rocky_JS

Rocky_JS

'cuda
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I picked up a fresh 340 engine as part of a deal. I am considering putting it in my 67 barracuda, but the crankshaft is for an Auto trans and I am running a 4spd and would like to keep it that way.
What options do I have to accomplish this - special bushings and such? I have read that some cranks are rough drilled already and can accommodate the input shaft others not. how can I tell? drilled depth?
 
There will be a pilot hole for the torque converter snout. This is found on all cranks, no matter what.

There's usually a smaller hole down inside that. This is either rough drilled, or finished for the crank bushing. Doesn't matter.

Get P5007051. It's this lil' guy:

bearing.gif

He lives in the auto trans pilot hole. I KNOW you have that!

If you have either the rough drilled or finished hole (Doesn't matter which), you're golden. If there's an old bushing there, pack the old bushing full of grease, drive a snug-fitting bolt in there to drive the bushing out, slam the new roller bearing home. Done

If you're crank is completely undrilled, grab the whizzer wheel and drop an inch off the tip of the input shaft. Slam the roller bearing home. Done.

I steer clear of the thin-wall bushing and even the stock bushing. The smaller pilot that's not finished may not be concentric which makes the thin-wall bushing a joke, and the stocker is fine if your crank is finished, but most aren't. With the roller, ALL cranks are manual-trans cranks!
 
Thanks gear and Jos

I used the link and got the part number for the national bearing FC69907. I will have the lady grab one at work, since i'm on vacation, and the project will continue!
I just took a rough measurement on the depth of the current pilot hole since the engine stand in the way of using a mic. I get a rough depth of a hair over 2.5in which seems it should be deep enough to fit the input shaft w/o modification?
 
Ok, I have removed the oil pan because of unknown bottom end and no harmonic balancer with engine and too many variables
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Pistons are KB silvolite 1267-060 cast pistons (10.2 CR with 65cc? heads), and crankshaft unfortunately is a non 340 cast 2658278 with no hole through the rod journals, and 1618699 LD rods, but I do not intend to spin this thing up to maybe 6k rarely - will this rotating assy be ok? I assume so....
what balancer do I need to use on this crankshaft?

The heads are small valve 587's, but fresh with all new valves I do have a pair of J small valve heads which I am considering maybe putting 2.02's in? what would be the ad/disvantage to doing this.

I am considering maybe a 284 484 cam and will be using early hp manifolds. again 4-spd trans.
 
oldkimmer said:
.............I would get it balanced.........keep the unleaded heads....u need a neutral balancer....kim................
Click to expand...
Yup, the balancer can come off any internally balanced small block. I would match it to the timing cover and crank pulley you're using but if you find a nice one, you can re-mark the timing slot and egg out the pulley hole. The 1.88 valve 587's and 1.88 valve 915's (J heads) are real close so I would swap them unless you plan on some major changes.
 
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