How many times can rod and main bolts be torqued?

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krazykuda said:
To reach proper clamp load, the fastener does get some plastic deformation. It is minimal.

A little plastic deformation won't hurt you, but as it keeps adding up, it will.

As in my first post in this thread, you can use them 4-5 times, after that you are pushing it...


This was also verified by the op calling ARP and they recommended 4 clamp cycles....
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Vote for most reasonable post.
 
I worked for CAT as well, the dealership up here was called Toromont Industries. Banged the boss wife and got laid off.....
 
4spdragtop said:
I worked for CAT as well, the dealership up here was called Toromont Industries. Banged the boss wife and got laid off.....
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Well, what did you expect.... :violent1:


You shouldn't get your meat where you get your potatoes.... #-o
 
krazykuda said:
Everything I first posted has come out to be right. ..... :D
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If you were right, unfortunately your experience has no relevance to the OP's question. Did you read the Tech section from ARP? ARP does not torque past yield! They do not allow plastic deformation! After .0005 of plastic deformation they say throw the fastener away. Read torkflight's post. It includes the best way to check the stretch with the tapered holes in each end of the bolt, already there from ARP. Here is real world experience with real results. We are not buying OEM bolts to put in our HP Mopars, we are using better fasteners. Designed and tested by Engineers to outperform OEM. I see you are one of those guys who always has to be "right", whether you are or not.
 
66fs said:
If you were right, unfortunately your experience has no relevance to the OP's question. Did you read the Tech section from ARP? ARP does not torque past yield! They do not allow plastic deformation! After .0005 of plastic deformation they say throw the fastener away. Read torkflight's post. It includes the best way to check the stretch with the tapered holes in each end of the bolt, already there from ARP. Here is real world experience with real results. We are not buying OEM bolts to put in our HP Mopars, we are using better fasteners. Designed and tested by Engineers to outperform OEM. I see you are one of those guys who always has to be "right", whether you are or not.
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:happy1:
 
66fs said:
If you were right, unfortunately your experience has no relevance to the OP's question. Did you read the Tech section from ARP? ARP does not torque past yield! They do not allow plastic deformation! After .0005 of plastic deformation they say throw the fastener away. Read torkflight's post. It includes the best way to check the stretch with the tapered holes in each end of the bolt, already there from ARP. Here is real world experience with real results. We are not buying OEM bolts to put in our HP Mopars, we are using better fasteners. Designed and tested by Engineers to outperform OEM. I see you are one of those guys who always has to be "right", whether you are or not.
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Arguing with you isn't going to help the op with his question...


Good day.... :glasses7:
 
hmmm, only 4 or 5 times for torquing - doesn't give you much slack when putting together a new engine...

receive the new rods - already torqued once
check bearing clearances, there's number two
assemble engine, there's three
 
Well I got my answer, although there are some disagreements on the methods the general consensus is similar lol.

I will re-use these rod bolts this time, but if it has to come apart again for whatever reason then I will get new ones, or just get new rods. Thanks everybody!
 
dartvadar said:
as i am about to get ready to put my 360 back together i just had the thought about how many times i can torque some of the bolts. Specifically the rod bolts, mains and head bolts.

The head bolts are arp bolts, and they have been torqued twice, the rod studs are arp as well and have been torqued twice. The mains are the stock bolts, and if you include when the motor was put together in 81 and when i put it together last time they have been torqued twice.

Should i get some new bolts? Or will i be fine with re-using them?
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4.
 
DartVadar said:
Well I got my answer, although there are some disagreements on the methods the general consensus is similar lol.

I will re-use these rod bolts this time, but if it has to come apart again for whatever reason then I will get new ones, or just get new rods. Thanks everybody!
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Good Call.
 
kielbasa said:
hmmm, only 4 or 5 times for torquing - doesn't give you much slack when putting together a new engine...

receive the new rods - already torqued once
check bearing clearances, there's number two
assemble engine, there's three
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Exactly!

Someone gets it.... :cheers:
 
DartVadar said:
Well I got my answer, although there are some disagreements on the methods the general consensus is similar lol.

I will re-use these rod bolts this time, but if it has to come apart againid for whatesver reason then I will get new ones, or just get new rods. Thanks everybody!
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Is it a street /strip engine or just street ? If just street use, they should be OK. APR makes good stuff, I reused my head bolts a few times and they still torque fine--

Rod bolts are under more stress but for mild street engines, they aren't stressed that much. Keep in mind I'm thinking of stock stroke engines, any engine with a 4 inch stroke is going to put much more stress on everything, including the rod bolts. Another killer is rpm, a stock stroke 340 can handle 6,000 rpms better then a 408 at 5,500 rpm. It comes down to piston speed.

Just don't put a solid cam in it and hit 7,000 each time you shift gears. If you keep the rpms on a 360 to 5,500 or less, I see no problems as long as the compression isn't too high or the timing is not off..better to have slightly not enough timing vs slightly too much
 
dodge freak said:
Is it a street /strip engine or just street ? If just street use, they should be OK. APR makes good stuff, I reused my head bolts a few times and they still torque fine--

Rod bolts are under more stress but for mild street engines, they aren't stressed that much. Keep in mind I'm thinking of stock stroke engines, any engine with a 4 inch stroke is going to put much more stress on everything, including the rod bolts. Another killer is rpm, a stock stroke 340 can handle 6,000 rpms better then a 408 at 5,500 rpm. It comes down to piston speed.

Just don't put a solid cam in it and hit 7,000 each time you shift gears. If you keep the rpms on a 360 to 5,500 or less, I see no problems as long as the compression isn't too high or the timing is not off..better to have slightly not enough timing vs slightly too much
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I have a stock stroke in it still, and it's really only a street motor, maybe a little bit of strip, but I doubt it. Now I am putting a solid roller cam in it, but still not going to shift at 7k anyways. Last time running it I think the highest I revved it was 5400 anyways, so even though it can rev high because of the solid cam, doesn't mean I will really.
 
Just as an example.. A friend ran NHRA Stock Eliminator. He was on the 2-step at 6800, shifted at 7200, and trapped at 8K. The engine had stock pistons, stock rods. Those rod bolted have tens of cycles on them between teardowns for inspection, occasional piston replacements, and record tear downs.
If you don't over torque, you can retorque them many, many times. But - the one time you go too far, they're junk.
 
moper said:
Just as an example.. A friend ran NHRA Stock Eliminator. He was on the 2-step at 6800, shifted at 7200, and trapped at 8K. The engine had stock pistons, stock rods. Those rod bolted have tens of cycles on them between teardowns for inspection, occasional piston replacements, and record tear downs.
If you don't over torque, you can retorque them many, many times. But - the one time you go too far, they're junk.
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That's pretty impressive for stock parts, yeah I definitely won't be winding it that high. And yea correctly torquing them is key. What is the oiling capabilities of a stock 360 anyways?

I'm sure there are a few cases like 70aarcuda posted about failures in the bottom end, but on a street car how many failures are directly attributed to rod bolts alone? I've seen failures that are originally caused by lack of oil, but has a or would a rod cap just fly off from a broken bolt?
 
moper said:
Just as an example.. A friend ran NHRA Stock Eliminator. He was on the 2-step at 6800, shifted at 7200, and trapped at 8K. The engine had stock pistons, stock rods. Those rod bolted have tens of cycles on them between teardowns for inspection, occasional piston replacements, and record tear downs.
If you don't over torque, you can retorque them many, many times. But - the one time you go too far, they're junk.
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Does he really have "Stock pistons and Stock Rods"....or does he have Nhra approved replacement pistons and rods...which are forged pistons and rods...?

[ame]http://www.nhra.com/userfiles/file/NHRAAcceptedProducts.pdf[/ame]

Look on page 35 and 35 for the 340 and 360 Stock replacement pistons...i see Diamonds...Ross..CP ..JE...Venolia ...and Arias pistons listed....and the old TRW L2316F....Wonder how many stockers are running around with those anchors...LOL

And on page 76 the list of approved Rods .........even a large journal small block chevy and LS1 rod is legal in a mopar...LOL.....Stocker...yeah right..
 
70aarcuda said:
Does he really have "Stock pistons and Stock Rods"....or does he have Nhra approved replacement pistons and rods...which are forged pistons and rods...?

http://www.nhra.com/userfiles/file/NHRAAcceptedProducts.pdf

Look on page 35 and 35 for the 340 and 360 Stock replacement pistons...i see Diamonds...Ross..CP ..JE...Venolia ...and Arias pistons listed....and the old TRW L2316F....Wonder how many stockers are running around with those anchors...LOL

And on page 76 the list of approved Rods .........even a large journal small block chevy and LS1 rod is legal in a mopar...LOL.....Stocker...yeah right..
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how about arp 2000 7/16 capscrews ?:banghead::banghead:
 
70aarcuda said:
Does he really have "Stock pistons and Stock Rods"....or does he have Nhra approved replacement pistons and rods...which are forged pistons and rods...?
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This was back in the early 90s. The pistons were J&E but were same weight, same compression height, same dome design, same ring package as stock factory (351 Cleveland). He'd buy 12 at a time so he always had exact replacements should he have a problem. Rods were stock Ford castings, hand picked, weight and length matched, shot peened, running ARP bolts. Again, he'd have a couple spares weight matched too just in case. This engine held National records in 3-4 different Stock Eliminator classes: D,E,F, and M (IIRC with a 2bbl for the M), and I would swear on a stack of bibles there was never any cheating on his part. He'd even have extra tolerance built in on things like valve angles, seat angles, displacement, volumes, etc. just in case the NHRA inspectors messed up. So yes, this was as stock as NHRA would allow at the time - which was pretty much stock factory with some exceptions. He currently races SS/EA and it usually top ten material.

Regardless - it never had clamping issues with a rod and those bolts were on and off dozens of times during the season.
 
moper said:
This was back in the early 90s. The pistons were J&E but were same weight, same compression height, same dome design, same ring package as stock factory (351 Cleveland). He'd buy 12 at a time so he always had exact replacements should he have a problem. Rods were stock Ford castings, hand picked, weight and length matched, shot peened, running ARP bolts. Again, he'd have a couple spares weight matched too just in case. This engine held National records in 3-4 different Stock Eliminator classes: D,E,F, and M (IIRC with a 2bbl for the M), and I would swear on a stack of bibles there was never any cheating on his part. He'd even have extra tolerance built in on things like valve angles, seat angles, displacement, volumes, etc. just in case the NHRA inspectors messed up. So yes, this was as stock as NHRA would allow at the time - which was pretty much stock factory with some exceptions. He currently races SS/EA and it usually top ten material.

Regardless - it never had clamping issues with a rod and those bolts were on and off dozens of times during the season.
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Back when Stock and Super Stock mean't no porting and stock weight internals.
 
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