Debunking the Aluminum Rod Myth

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69 Cuda 440

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~ Debunking the Aluminum Connecting-Rod Myth ~

#1 > All Connecting Rods stretch.

#2 > Re-using the Rod depends entirely on the previous application.

#3 > Aluminum-Rods will stretch approximately .010" more than a Steel Rod.

#4 > Anybody who can analyze an Aluminum-Rod from a 'Myth' is a 'Banana'.

#5 > There is more to it than just saying > "A used Aluminum-Rod is no good."

#6 > There a several different types of analysis {inspection} to determine if an
Aluminum-Rod can be re-installed in an Engine.

#7 > The area of the most concern, is the Large-End {Rod Journal}, as with extended
use or high-revving, the Large-End can tend to get 'oblong'.
 
It doesn't make anyone a banana if they simply do not WANT to run aluminum rods. I do not prefer them.

But I was already a banana.

I think what most everyone meant on the recent thread was that "they" (along with myself) did not want to give the poster asking the question possible advice that might lead to an engine failure. That's the last thing I want when giving someone advice. Better to be safe than sorry as they say.
 
RustyRatRod said:
It doesn't make anyone a banana if they simply do not WANT to run aluminum rods. I do not prefer them.

But I was already a banana.

I think what most everyone meant on the recent thread was that "they" (along with myself) did not want to give the poster asking the question possible advice that might lead to an engine failure. That's the last thing I want when giving someone advice. Better to be safe than sorry as they say.
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Well Stated,

I think the 'OP' was over-zealous in his purchase, thinking he got a 'steal' on
some old Racing Parts.

On 'Aluminum Rods', you need to know where they have been before.

PC

P.S.

Rusty, you are a Good Banana..........
 
I'm a huge fan of aluminum connecting rods. V2 air conditioner Compressors never seem to die.

That said, fatigue life is finite and aluminum rods are certainly fully certifiable to run.

It's just that by the time you pay for it, you could a bought new ones.
 
jos51700 said:
I'm a huge fan of aluminum connecting rods. V2 air conditioner Compressors never seem to die.

That said, fatigue life is finite and aluminum rods are certainly fully certifiable to run.

It's just that by the time you pay for it, you could a bought new ones.
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why were they pulled out? someone was getting worried about them, or they wouldn`t be used !!
 
It's not so much the big end getting oblong (I think the term is 4th out of round, or oval) is that they shrink with every heat cycle. So, clearance gets ate up, bearing grabs the crank and off goes the bone.

The other issue with aluminum rods is that stupid serrated cap. That one issue made me reduce aluminum rod us by 90 % (any real drag engine has aluminum rods and some corner turning engines do as well, tho not many roundy-round types admit to this).

The I found Groden rods and regained my faith in aluminum rods. His way of cap to rod mounting is fool proof (but not idiot proof, as nothing is idiot proof).

There was also a rod manufacturer who was developing a process that coated the rod and was the super hot ticket in Comp and PS for a while, but the pin heads at NHRA banned them. If I can remember the name I will post it later.
 
I guess putting used aluminum rods in an engine really depends on what you are doing........if you don't have a ton of coin wrapped up in it ( and the term ton is relative to each individuals net worth ) and you like to gamble , I'd say go for it.
If you have any real money in the rest of the motor , that 100.00 could cost you thousands.
Is it worth it ?
**** no.
I don't see it as a myth.
It is an unknown and uncontrollable variable.
A gamble.
With a stock block and a bargain basement top end , hell , you can build another for cheap.......relatively speaking.
I still wouldn't do it though.
 
I have ran BME in 440's well beyond the "accepted" run time without a rod failure to date. As with any piece of the package it all has to do with using that part within it's limits!
 
69 Cuda 440 said:
Well Stated,

I think the 'OP' was over-zealous in his purchase, thinking he got a 'steal' on
some old Racing Parts.

On 'Aluminum Rods', you need to know where they have been before.

PC

P.S.

Rusty, you are a Good Banana..........
Click to expand...

Thanks, Paul. That means a lot coming from you.
 
A lot of the so called stretch is actually expansion from heat. Just like a piston. If all these terrible things happen to an aluminum rod, why doesn't it affect pistons the same way?
 
What no one has covered is where most of the real stretch comes from and that is the rod bolts. They are designed to stretch and rebound ever such a miniscule amount. This is why I always smile to myself when I hear guys revving their engines needlessly in the staging lanes at the strip. If you don't think the rod bolts act in that way, you got another thing comin. This is why you have to be careful running a quench engine, because that's where most of the stretch comes from. Rod bolts. People don't normally think about it, but it's true. That's how and why the big end starts having trouble first.
 
SGBARRACUDA said:
I have ran BME in 440's well beyond the "accepted" run time without a rod failure to date. As with any piece of the package it all has to do with using that part within it's limits!
Click to expand...

Yup. They are like anything else. Good parts, machine work and assembly counts for a lot.
 
SGBARRACUDA said:
I have ran BME in 440's well beyond the "accepted" run time without a rod failure to date. As with any piece of the package it all has to do with using that part within it's limits!
Click to expand...

Exacto Mundo 'SG'.

'Understandably' > Previously used Aluminum Rods scare most everybody.

But it's 'what you know' about them Rods, that makes the difference.

Regarding 'Mickey Thompson' Aluminum-Rods.

'Harvey Aluminum Company' did the forgings. They were pretty good units,
and could take a pounding without getting distorted. They were 'thick' Bastards.

If they came out of a 'non' Supercharged Engine {ie; Modified Production} or
a 'Carburetor' Gasser, they were good for at least '300' hard runs.
 
madscientist said:
There was also a rod manufacturer who was developing a process that coated the rod and was the super hot ticket in Comp and PS for a while, but the pin heads at NHRA banned them. If I can remember the name I will post it later.
Click to expand...

You mean the Kirk Jager stuff? S/F....Ken M
 
SGBARRACUDA said:
I have ran BME in 440's well beyond the "accepted" run time without a rod failure to date. As with any piece of the package it all has to do with using that part within it's limits!
Click to expand...

Bought used ?
I am thinking no , but for clarity I'm curious.
Am I wrong , or did this thread grow out of a member asking if he was getting a bargain on a used set of connecting rods that he knew nothing of the history of ?
It seems to be growing into an apples to rutabagas kind of comparison.
If you know the history , you eliminate an important variable that should steer your decision.
If all you know is the price , you don't know anything.
 
tubtar said:
Bought used ?
I am thinking no , but for clarity I'm curious.
Am I wrong , or did this thread grow out of a member asking if he was getting a bargain on a used set of connecting rods that he knew nothing of the history of ?
It seems to be growing into an apples to rutabagas kind of comparison.
If you know the history , you eliminate an important variable that should steer your decision.
If all you know is the price , you don't know anything.
Click to expand...

This ^ makes good sense.
 
[ame="https://www.youtube.com/watch?v=eTmoCM2iw8A"]Larry Vee: Is This Anything? (Letterman 1/7/2003) - YouTube[/ame]


I won''t be using any luminous rods, new, used, stolen, gifted, or found on side of the road, and certainly not "repaired" retired or disabled ones. That is all
 
69 Cuda 440 said:
Salem, Massachusetts

Don't you 'witches' worship the 'Great Banana' up there.
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When you say "Great Banana" are you referring to the Golden Banana on route 1 in Peabody, MA? If so, then yes lol. (if you have no idea what i'm talking about google the Golden Banana and you'll know)
 
71Scamper said:
When you say "Great Banana" are you referring to the Golden Banana on route 1 in Peabody, MA? If so, then yes lol. (if you have no idea what i'm talking about google the Golden Banana and you'll know)
Click to expand...

Is that near the 'Gay Bar' called "The Loose Banana'.
 
69 Cuda 440 said:
Very Odd,

A guy that goes by the name of '71Scamper'. And you don't know where
all the 'caboose joints' are.
Click to expand...

Now that's a hoot right there, I don't care who you are.
 
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