how far can one turn down a crank?

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With that compression you'll need aluminum heads and a decent sized cam to knock down the DCR for pump fuel. But if you're only making a few beer runs race fuel isn't a big deal...
 
We ground my 440 steel crank down .125 to fit the 383 block i had. Hd to cut .100 off the counterweights to clear the block as well.
 
problem with a chevy rod is it is not as wide as a mopar rod. = too much side clearance. the smoked journal needs to be measured.
 
#1, the extra side clearance won't hurt a thing and #2, if it bothers you that much Eagle, Manley, Molnar and probably others make a 7.100/.990 rod that is Mopar width on the big end. 440 Source has a 7.100/2.20/.990 rod for their cranks but I don't know what the big end width end is.
 
And if you want to go back to like new,get it welded and reground. And have everything checked out. Marine Crankshaft,Long Beach Ca. can send it back better than new. Excellant work,good prices,good turn around. Wouldnt hurt to give them a call.....
 
Seems like you guys are making this way too hard. If the OP is having questions like he is, he needs to turn th crank until it cleans up and go. He don't need to worry about offset grinding and all that.

That said, the Chrysler rod journal is way too big to start. The BBC is plenty big and 2.100 is about good for most conventional BB stroke lengths. When the stroke lengths are short, you can use 2.00 or even 1.88 rod throws and it's much better.
 
This got me thinking today as I opened up the bottom end.

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bought a 340 duster in 92,..gave it mortal hell till 99, man i traded it to pulled motor and tore it down even tho it run great and found one rod journal turned .040! never could tell turning 7500 rpm erry day!! you could get that one journal repaired and turned back standerd but thats costly! i always felt all rod journals should be same size for balance but just my opinion...
 
.............I have had 440 cast cranks offset ground .060 on the rods. U gain a little extra stroke as well as a point of compression..........kim.....
 
also check out the quality of the origin of that crank. some say 440 source stuff comes from China....
Ya think? Cummins cranks are forged in China nowadays.....Id run it. Strokers dont turn alot of RPM's and if its in fact forged (yup, shot peening gives it the cast look) , Id think it would be plenty strong. "... the cranks are nitrated using a plasma gas nitrating process. This nitrating process penetrates approximately .014" deep into the steel, and raises the surface hardness of the cranks to a MINIMUM Rockwell hardness of 52-60 on the C scale..." That means the depth of the hardening is deeper than an initial .010 journal cut so you should be good to go. BTW you can weld up a forged crank too. Had a nasty .030 cut 340 forged crank spin a rod, crank shop welded journal up and recut it, could not tell it was even touched. The guy said it was a very good OEM crank.
 
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