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Aluminum rod reduces shock load to crank

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Aluminum rod reduces shock load to crank

Postby Truckedup » Thu Apr 18, 2013 5:41 am

Ok,does an aluminum rod really transmit less shock to the crankshaft compared to a steel rod? Performance aluminum rod manufacturers make this claim.Yes,I know aluminum rods have a short life span. :D
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Re: Aluminum rod reduces shock load to crank

Postby Ron E » Thu Apr 18, 2013 7:27 am

The nitro guys claim they're an absolute necessity for that very reason. More realistic combinations, I'm not sure either. Seem likely it could buffer the bottom end during detonation.
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Re: Aluminum rod reduces shock load to crank

Postby Warp Speed » Thu Apr 18, 2013 8:53 am

Truckedup wrote:Ok,does an aluminum rod really transmit less shock to the crankshaft compared to a steel rod? Performance aluminum rod manufacturers make this claim.Yes,I know aluminum rods have a short life span. :D


Yes it does......

It also soaks up work to a certain extent. Work compressing the rod that could be used to turn the wheels.
Only needed, recomended, advantagous when serious cylinder pressures are present.
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Re: Aluminum rod reduces shock load to crank

Postby Truckedup » Thu Apr 18, 2013 9:19 am

Taking it one step more.....Suppose you have an engine that's breaking crankshafts with steel rods.Lets say this engine is not an alcohol or nitro fuel engine.. Would the crank last longer with aluminum rods? Yes,many variables,just a theory question.
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Re: Aluminum rod reduces shock load to crank

Postby Warp Speed » Thu Apr 18, 2013 9:54 am

Truckedup wrote:Taking it one step more.....Suppose you have an engine that's breaking crankshafts with steel rods.Lets say this engine is not an alcohol or nitro fuel engine.. Would the crank last longer with aluminum rods? Yes,many variables,just a theory question.


I would fix the reason it is breaking cranks!!

Tune up, crank quality/design for application ect......
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Re: Aluminum rod reduces shock load to crank

Postby Kevin Johnson » Thu Apr 18, 2013 10:06 am

Truckedup wrote:Taking it one step more.....Suppose you have an engine that's breaking crankshafts with steel rods.Lets say this engine is not an alcohol or nitro fuel engine.. Would the crank last longer with aluminum rods? Yes,many variables,just a theory question.


There are too many variables. Moreover, merely stating "variables" tends to imply that higher order combinations of variables (and variables themselves) can be directly equated. Look at how Transcendental numbers differ fundamentally from numbers that are algebraic http://en.wikipedia.org/wiki/Transcendental_number

You need to guard against the fallacy of equivocation.
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Re: Aluminum rod reduces shock load to crank

Postby Warp Speed » Thu Apr 18, 2013 11:05 am

Kevin Johnson wrote:
Truckedup wrote:Taking it one step more.....Suppose you have an engine that's breaking crankshafts with steel rods.Lets say this engine is not an alcohol or nitro fuel engine.. Would the crank last longer with aluminum rods? Yes,many variables,just a theory question.


There are too many variables. Moreover, merely stating "variables" tends to imply that higher order combinations of variables (and variables themselves) can be directly equated. Look at how Transcendental numbers differ fundamentally from numbers that are algebraic http://en.wikipedia.org/wiki/Transcendental_number

You need to guard against the fallacy of equivocation.


Really???????

Why can't you just give your opinion on the subject instead of trying to turn EVERY topic into a science project?
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Re: Aluminum rod reduces shock load to crank

Postby DaveMcLain » Thu Apr 18, 2013 11:19 am

Can you run a lesser crank and block longer at very high loading and or rpm with an aluminum rod? Absolutely. Bearing life will be better too.
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Re: Aluminum rod reduces shock load to crank

Postby SchmidtMotorWorks » Thu Apr 18, 2013 11:34 am

On a current Nitro car with a competitive tune the force on the rod is enough to deform the rod in a way that spreads the bore.
Presently there is only one rod design and material that is holding up for aggressive tune-ups.
The material and forging process is patented so only one supplier can make them for now.
http://www.alanjohnsonperformance.com/
One of the few times that a patent had any significant impact on a technology in drag racing.

If/when power levels increase it may be nessesary to find an alternative rod design and or material.
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Re: Aluminum rod reduces shock load to crank

Postby Dave Koehler » Thu Apr 18, 2013 11:41 am

Jon,
I only see Brooks and C&A on AJs site. Was there something else you wanted us to see?

Kevin.
STOP IT
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Re: Aluminum rod reduces shock load to crank

Postby Kevin Johnson » Thu Apr 18, 2013 11:53 am

Warp Speed wrote:
Kevin Johnson wrote:
Truckedup wrote:Taking it one step more.....Suppose you have an engine that's breaking crankshafts with steel rods.Lets say this engine is not an alcohol or nitro fuel engine.. Would the crank last longer with aluminum rods? Yes,many variables,just a theory question.


There are too many variables. Moreover, merely stating "variables" tends to imply that higher order combinations of variables (and variables themselves) can be directly equated. Look at how Transcendental numbers differ fundamentally from numbers that are algebraic http://en.wikipedia.org/wiki/Transcendental_number

You need to guard against the fallacy of equivocation.


Really???????

Why can't you just give your opinion on the subject instead of trying to turn EVERY topic into a science project?



I think there is an ignore function with the board. I do not think you or anyone else needs my permission to use it.
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Re: Aluminum rod reduces shock load to crank

Postby SchmidtMotorWorks » Thu Apr 18, 2013 12:40 pm

Dave Koehler wrote:Jon,
I only see Brooks and C&A on AJs site. Was there something else you wanted us to see?

Kevin.
STOP IT


I'll take a picture of one of the rods when I get home and post it.
It might be that only some teams are allowed to buy them.
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Re: Aluminum rod reduces shock load to crank

Postby Warp Speed » Thu Apr 18, 2013 1:14 pm

SchmidtMotorWorks wrote:
Dave Koehler wrote:Jon,
I only see Brooks and C&A on AJs site. Was there something else you wanted us to see?

Kevin.
STOP IT


I'll take a picture of one of the rods when I get home and post it.
It might be that only some teams are allowed to buy them.


Yep.......gotta be on "the deal" ! :wink:
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Re: Aluminum rod reduces shock load to crank

Postby Barbapapa » Thu Apr 18, 2013 1:23 pm

Is the rod handling compression forces really key or are other rods on the downstroke acting to dampen by acting as extension springs?
The idea of the rod being so useful in compression seems counterintuative to me, if shock damping under power compression is key then why aren't the wrist pin and piston design considered more?
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Re: Aluminum rod reduces shock load to crank

Postby Kevin Johnson » Thu Apr 18, 2013 1:47 pm

http://www.google.com/patents/US6502480

For those still paying attention.
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