balance ?

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dirty white boy

50 yr old Juvenal delinquent
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when using a 360 crank in a stroker 318 build, what best cheapest way to balance it all out? 318 car, converter and all what im working with. would it be best to use a LA crank or a magnum?
 
You realise that the "Main Journals are LARGER on a 360. compared to a 318/340.....Right?
 
cheapest.....360 weighted balancer and B&M weighted flexplate for 360......
 
You'll also be turning down the counter weights or machining the piston skirts. The 318 piston won't clear the counter weights of the crank. Do they make a piston for this application?
 
Hours later. It can be done. Cheaper for you to buy one.
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You'll also be turning down the counter weights or machining the piston skirts. The 318 piston won't clear the counter weights of the crank. Do they make a piston for this application?

The way I read it is, you buy Silvolite .030 318 pistons with 1.741 compression height, and mill .065 off the tops. Then you mill the skirts to clear the counterweights. Makes a 347 CI motor. I would have to look up the price of a 3.58 stroke crank with 318 size mains to believe it would be cheaper than turning the 360 crank mains. If it is cheaper that way, the price of turning a crank must have skyrocketed in the last few years. :eek:
 
You cut through the hardness of the crank good luck keeping bearings in it. They will stick fast like an Alabama tick when they get heat in them. Buy a crank or pay to get it cut then rehardened and balanced for more than the cost of a new stroker kit.

Price the work out that you'll need to do using that out of balance 360 cast crank. Just like rods it is cheaper to buy new then resize your old rods. I would get a Scat forged rotating assembly. No guess work.
 
400 for cast crank 800 forged and the above mentioned silver-lite pistons, forged pistons really needed but. cheaper to buy cast crank than buy flexplate 100 bucks, and balancer 100+ then pay to turn crank, buy a crank as i dont have one. it all adds up to mega-mopar bucks!!
 
It's easier to understand the difference when someone like @Oldmanmopar explains it so it makes sense! The cut required on the 360 mains would require getting it heat treated again, and I forgot that part. I tend to pretty much stick to stock type builds anyway. It's 60 or 80 miles to a drag strip in any direction from my house, and traffic is too congested to mash on anything around here unless you go out and do it at 3 AM. At 62....I'm too dang old to be out prowling around that time of night! :realcrazy:
 
It's easier to understand the difference when someone like @Oldmanmopar explains it so it makes sense! The cut required on the 360 mains would require getting it heat treated again, and I forgot that part. I tend to pretty much stick to stock type builds anyway. It's 60 or 80 miles to a drag strip in any direction from my house, and traffic is too congested to mash on anything around here unless you go out and do it at 3 AM. At 62....I'm too dang old to be out prowling around that time of night! :realcrazy:
If that is the case, what is wrong with a 360 to start with? There are plenty of them around, perhaps moreso than 318s
 
You cut through the hardness of the crank good luck keeping bearings in it. They will stick fast like an Alabama tick when they get heat in them. Buy a crank or pay to get it cut then rehardened and balanced for more than the cost of a new stroker kit.

I'll more than a little puzzled by this.......I have never heard of thru hardening a cast crank.......I'm not even sure if it is possible.....only crankshafts that were hardened to my knowledge were Hemi, 318-3 truck engine crank, and they were only surface hardened, first .010 cut on the crank removed the hardened materail
 
If that is the case, what is wrong with a 360 to start with? There are plenty of them around, perhaps moreso than 318s

Yep....a lot easier for sure! Not many 360's pop up around here though. The most popular performance engine builder in our area needed a 360 a while back, and couldn't find one. I traded him a 360 I had laying around for a balance job on my next rotating assembly that I will need before long. I have a ton of 318's, and might even do one of the 340's I have hoarded up....lol.
 
The deal breaker IMO is there isn't a good piston for the 318 block 3.58 stroke combo. Might as well do a 390 cube SCAT cast crank stroker kit as they can be had fairly cheap.
 
cast cranks are heat treated ??? forgot the ???
done that 360>340 main grind many times
works fine
be sure and polish correct direction and chamfer the oil holes etc
if you do get a new crank get a 4" lots of combinations available
 
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I've had one of these engines in a daily for the last 25years and never had any problems with the crank or bearings and it's had a very hard life, countless quarter mile runs, aussie burnout comps, long state to state drives. I had a mate build it on a budget back when stroker cranks were exotic and pricey, infact I'd never seen any for sale here in Australia at the time so it was a cheap alternative to a performance engine, even cheaper than sourcing a 360 here, hard to believe yes but the 360 wasn't here in big numbers but the 318 was..
 
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