Connecting Rods needed for try his crank

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My son builds many stroker motors. All brands, But we live and breath mopar for our own. We usually end up with the factory rotating assembles and at times the builders buy race blocks so we have blocks . Parts are stacking up 4 blocks per pallet and lost count of pallets taken to the other shop to store.

Do we have time to list them? No But I like helping people that have no or little income and need parts. When reading help or wanted threads you can pick out the real needy even if the thread is in the wrong category which i find myself doing. Why not Change the thread category and leave the help/offer posted.

$100 dollars for a polished standard 340 forged crank isn't a sale its a give away. Some of these mods are either jealous or want to grab the parts for themselves. Who sent a member my E-mail after taking the post down? Asking for a specific item not listed on any other site seems obvious what is going on here.
 
For rods, Scat I-beams are hard to beat. They are are cheap, light weight, and can handle quite a bit of power. I have a set in my 408 that runs low 10's.
 
Oldmanmopar said:
My son builds many stroker motors. All brands, But we live and breath mopar for our own. We usually end up with the factory rotating assembles and at times the builders buy race blocks so we have blocks . Parts are stacking up 4 blocks per pallet and lost count of pallets taken to the other shop to store.

Do we have time to list them? No But I like helping people that have no or little income and need parts. When reading help or wanted threads you can pick out the real needy even if the thread is in the wrong category which i find myself doing. Why not Change the thread category and leave the help/offer posted.

$100 dollars for a polished standard 340 forged crank isn't a sale its a give away. Some of these mods are either jealous or want to grab the parts for themselves. Who sent a member my E-mail after taking the post down? Asking for a specific item not listed on any other site seems obvious what is going on here.
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Might just want start a conversation instead of just posting on a thread. I feel the same way about helping others.
 
66fs said:
Might just want start a conversation instead of just posting on a thread. I feel the same way about helping others.
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Here is the issue with that. If I had one item to help one person that would be fine but letting all know that the parts are here incase the original poster is not interested may just help someone else .

My post was taken down because they said it wasn't a wanted thread . Read the first paragraph. I believe he was asking for help. Why not move his thread to the proper forum like they always do to me and others. UNLESS there was another agenda? "Like take it down and let your friends know to contact me through E-mail and not PM." Undercut the member asking for help.
I am sorry that is how I see it and this is not the first time. Who gave out my E-mail???? That was what made me see this how I do.
 
Once the journals are cleaned, mic 'em and look for scratches that will hang your fingernail. If it is smooth, maybe just a polish. If your gonna store a crank, I found vaseline on the journals works for eternity unless your in a 120F plus environment and then it may sag.
 
Bewy said:
With new rods being so cheap, I wouldn't even bother trying to find some used rods of questionable condition that may need $$$ put into them. New rods, better steel, better bolts.
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Chinese steel is better than Ma Mopar's steel?
 
Yes, it might well be if you compared the steel grade. It is not solely the metallurgy of the rods. If you get new H beams, you get 7/16" bolts. Original fasteners were nuts & bolts, bolts which were smaller in diameter & reduced clamp force where you want maximum strength. Cutting the factory rod for the bolt head did two things that further weakened the rod: introduce a sharp edge & removed material in a vital spot. Then you have the precision CNC machining of new rods on modern equipment, compared to a shop closing & honing old factory rods by hand. If the old rods have pressed pins, new pins will never be as tight as the originals.
Is that enough reasons?
 
Well I cleaned the crank and the cylinder bores on the 340.
Crank mains appear to have been turned .010 interestingly the con rods were never turned.
The block also has never been bored.

:thumbsup:
 
Bronze Barracuda said:
Well I cleaned the crank and the cylinder bores on the 340.
Crank mains appear to have been turned .010 interestingly the con rods were never turned.
The block also has never been bored.

:thumbsup:
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The block also has never been bored
Guessing it was stored facing a monitor showing continuous reruns of I Dream of Jeannie.
 
Bronze Barracuda said:
Well I cleaned the crank and the cylinder bores on the 340.
Crank mains appear to have been turned .010 interestingly the con rods were never turned.
The block also has never been bored.

:thumbsup:
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I've seen virgin 340's with undersized crank journals. There are 340 blocks that have never been bored. I have a few myself. Nice find!
 
Bewy said:
Yes, it might well be if you compared the steel grade. It is not solely the metallurgy of the rods. If you get new H beams, you get 7/16" bolts. Original fasteners were nuts & bolts, bolts which were smaller in diameter & reduced clamp force where you want maximum strength. Cutting the factory rod for the bolt head did two things that further weakened the rod: introduce a sharp edge & removed material in a vital spot. Then you have the precision CNC machining of new rods on modern equipment, compared to a shop closing & honing old factory rods by hand. If the old rods have pressed pins, new pins will never be as tight as the originals.
Is that enough reasons?
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Never used new rods. Originals have been fine for me. By the time you get good rod bolts, recondition and equalize the rod length, they are plenty strong. But you may have more money or building more output than I run.
 
66fs said:
I've seen virgin 340's with undersized crank journals. There are 340 blocks that have never been bored. I have a few myself. Nice find!
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although the block has never been bore
66fs said:
I've seen virgin 340's with undersized crank journals. There are 340 blocks that have never been bored. I have a few myself. Nice find!
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Although the block has had an exciting life as it has clearly never been bored ;) It is in rough shape and will need to be oversized at least .010. it will still need to be checked for cracks etc. But with a little luck it'll definitely be a nice find at $250 for a virgin 1970 340 block heads and crank.
 
66,
I get what you are saying [ post 37 ]. But the OP doesn't have any rods, he has to get/buy some...
 
Bewy said:
66,
I get what you are saying [ post 37 ]. But the OP doesn't have any rods, he has to get/buy some...
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You are right in what you say. I remember talking to my machinist, years ago about rods. He said SBM rods were good to 7,000 rpm and could be used in blown applications. They are not weak kneed SBC rods. Just thinking of application. It all depends on cost and the whole picture. How much does your machine work cost, and do you trust them to do the work correctly. I am not faulting your logic.
 
Bewy said:
66,
I get what you are saying [ post 37 ]. But the OP doesn't have any rods, he has to get/buy some...
Click to expand...
True I will need some rods. Thankfully I've got time. Still up in the air new aluminum rods, H beam I beam, or some stock original rods. In regards to original rods, here is what I think I've learned so far through this thread.
All SBM rods can be used with any SBM from the LA 273 all the way to the Magnum 360. There are "floating" wrist pins and "press fit" wrist pins. It doesn't matter if you use press fit or floating so long as they are all the same? Does not matter what type of crank (cast or forged) nor what type of balancer (externally balanced or internally balanced)? But I believe the balancer you choose does matter depending on the crank, forged cranks are internally balanced and cast are externally balanced? All harmonic balancers prior to 71 are for internally balanced motors? All 360's are externally balanced? Not sure if there was a difference in regards to strength between the 318/340/&360 rods. The 273 were lighter and have a little less strength?
I may be wrong on some of these points.
 
Your in box is full. PM me when you get a chance. On the rods you're looking for.
 
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Bronze Barracuda said:
True I will need some rods. Thankfully I've got time. Still up in the air new aluminum rods, H beam I beam, or some stock original rods. In regards to original rods, here is what I think I've learned so far through this thread.
All SBM rods can be used with any SBM from the LA 273 all the way to the Magnum 360. There are "floating" wrist pins and "press fit" wrist pins. It doesn't matter if you use press fit or floating so long as they are all the same? Does not matter what type of crank (cast or forged) nor what type of balancer (externally balanced or internally balanced)? But I believe the balancer you choose does matter depending on the crank, forged cranks are internally balanced and cast are externally balanced? All harmonic balancers prior to 71 are for internally balanced motors? All 360's are externally balanced? Not sure if there was a difference in regards to strength between the 318/340/&360 rods. The 273 were lighter and have a little less strength?
I may be wrong on some of these points.
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Forget Aluminum Rods for the street. They are not worth the extra work. 273 / early rods are bushed and plenty strong for most applications. Some 340's also were balanced externally some 72 and all 73.
 
One issue with new H-Beam rods is, while they may produce some added benefits, they are often a lot heavier or could be lighter in some cases than the stock rods which will lead to having to rebalance the rotating assembly. This can be an unwanted and unexpected expense the OP isn't wanting to invest in at this time.
 
Under sized .030 main bearings for small block Mopar are getting harder to find, at least they were. I lucked out and bought a set off eBay. Rods are easier and you can always have it cut to Chevy size and use a 6.125 length rod. Heck when I hurt my 408 it went to Australia or somewhere as he said they cut it down to Honda size anyway. He paid me to much not to take that offer.
2-ICR6123-2124 Scat SB Chrysler Premium Pro Comp I Beam Connecting Rods
 
N
Bewy said:
Yes, it might well be if you compared the steel grade. It is not solely the metallurgy of the rods. If you get new H beams, you get 7/16" bolts. Original fasteners were nuts & bolts, bolts which were smaller in diameter & reduced clamp force where you want maximum strength. Cutting the factory rod for the bolt head did two things that further weakened the rod: introduce a sharp edge & removed material in a vital spot. Then you have the precision CNC machining of new rods on modern equipment, compared to a shop closing & honing old factory rods by hand. If the old rods have pressed pins, new pins will never be as tight as the originals.
Is that enough reasons?
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Nope....do you really trust the Chinese to supply the correct steel? Like they did with dog food, drywall and dozens of other products?

Personally I would run 340 rods before the ChiCom parts...

Rant over
 
AS said pick your parts and spend your money.....
 
Krooser,
I must have got reallllllllllllly lucky in the last 25 yrs. And so have 000s of others....
 
Krooser said:
N

Nope....do you really trust the Chinese to supply the correct steel? Like they did with dog food, drywall and dozens of other products?

Personally I would run 340 rods before the ChiCom parts...

Rant over
Click to expand...

The answer is almost certainly "It depends".

The Chinese are capable of building quality products, if you're willing to spend the money supervising them through the whole process, possibly including having someone on site to perform testing along the way. You won't get things for cents vs dollars, which is what most people buying Chinese made products are looking for.

But if you're an American company, and you need to have forgings cranked out by the thousands, you're willing to 50-75% of the direct cost to produce vs the US instead of 10%, and you have a robust QC process, you can make quality parts using Chinese vendors.

Scat sells tons of kits to US enthusiasts and has a good reputation for solid parts at a decent price. You can certainly get better out of a higher priced kit, from US sourced materials and machining, but you lose out on the lower end of the market.

Personally, I'd run a new rod, with new ARP bolts, machined and QC'd here in the US using a Chinese forging over a 50 year old factory rod that's been resized, rebushed and with new bolts/nuts. In the end you're buying from a US company that is putting it's name on the line, I believe that they're doing the checks and inspections required to utilize those Chinese forgings/castings.
 
Bewy said:
66,
I get what you are saying [ post 37 ]. But the OP doesn't have any rods, he has to get/buy some...
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I may have found some.
Started a new thread trying to figure out if these rods are floating pin rods? The rod/piston on the left casting number 3418645 it has a retainer clip so it may be a floating pin the one on the right is a lighter weight? 273 rod casting number 2406782

IMG_20220115_224235.jpg
 
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