Aluminum rod reduces shock load to crank

[Kevin Johnson]

what Al alloy are typically used?

In the patent, a key claim is that simply using a different aluminum alloy heretofore not used will result in a higher compressive yield strength and in this case will result in approximately a 25% increase over then-current state-of-the-art. The densities of the aluminum alloys are very similar to oneanother (as are the moduli of elasticity, as you point out).

... 2014-T6 aluminum alloy, which has a compressive yield strength of 58 ksi. More recently, 7075-T6 aluminum alloy has been used, which has a substantially higher compressive yield strength of 72 ksi.

... 7055-T77511, also referred to as HP007. This aluminum alloy has been available from Alcoa for some time, but never made into extruded bar stock for forging. By working with Alcoa, the inventors of the invention described herein obtained 7055-T77511 aluminum alloy from Aluminum Company of America “Alcoa” in extruded bar stock suitable for forging.

Under testing in drag racing engines generating in excess of 6,000 horsepower, the improved high performance aluminum connecting rod of the present invention has been found to have a compressive yield strength of 25 percent greater than 7075-T6.

... wherein said high performance aluminum connecting rod has a compressive yield strength of approximately 90 ksi.

[wyrmrider]

None of them have the compression dynamics of bionic nano-tubes
the parallel nano-tubes absorb detonation near TDC then rebound near maximum connecting rod angle returning the energy as reciprocating motion which is converted to rotating motion by the crankshaft.
No wasteful conversion to heat occurs
More compression, boost and spark advance are possible without destructive breakage
Tuning for detonation is actually beneficial

[Kevin Johnson]

https://www.youtube.com/watch?v=GV0AAF17LsI

I remember Woodstock taking place when I was about 8 years old, same as Jon.

About that time, some readers might remember, members of the public could get a small placard with a safety house on it for a front window to show that children could come there if they were in danger. We had one teenage girl show up that was on a bad trip, acting very paranoid. The police came to help her find her way home. Sad what people chose to do to themselves, I think. I think about that same time someone that was high on something jumped out of the Marina Tower in downtown Chicago. What a waste.

My parents are both marksmen and met each other at a rifle match. My father was an NRA instructor in his spare time.

[Kevin Johnson]

None of them have the compression dynamics of bionic nano-tubes
the parallel nano-tubes absorb detonation near TDC then rebound near maximum connecting rod angle returning the energy as reciprocating motion which is converted to rotating motion by the crankshaft.
No wasteful conversion to heat occurs
More compression, boost and spark advance are possible without destructive breakage
Tuning for detonation is actually beneficial

Yes, but then they discovered that the matrices formed perfect nets to capture all the excess ZDDP that people had dumped in trying to save their cams. That made the springs compress cock-eyed and wiped out the thrust bearings. Seemed like a great idea at the time though.

[wyrmrider]

Ah yes net matrices
I think I'll switch to elastic pistons
soak up extra cylinder pressure before and near TDC and when the piston rebounds add energy around 70 degrees ATDC
Think of the mechanical advantage
Turn most of the 50% of energy wasted as heat into power

[mike hohnstein]

Back in the day, colleague ran a 440RB Coronet with a 4 speed. Weary of breaking YL rods, he got a set of Carrillos, then he started breaking cranks. I always ran aluminum in my 8000+ rpm rats, only one failure when I cheaped out and used a set over, ONCE. That being said, aluminum rod breakage didn't waste the block the way a steel rod did once up on a time.

[MrBo]

Funny thing: I have seen stuff you would not expect to see. I have worked on high speed metal expanding presses with cast aluminum connecting rods. They had bronze rod & main crankshaft bearings and big ass aluminum rods.
Think that over for a bit. Aluminum.

I would estimate they ran for well over 40 years,
The platen on the press would move so fast, you could not really see it, just a blur.
The platen was cast aluminum too.

Some smart guy around the era of Taylor probably designed them, and would expect them to run a hundred years.

[wyrmrider]

Back in the day pistons were very heavy- around a 2 inch compression height
X@ on the rod scenario
we went to even longer rods than the stock 6.760 to help get the piston weight down

[RAS]

Hell no ! What shock load? Explain how this works. I thought there was a bearing and a film of oil under pressure on each end of the rod. Compress a liquid. Really !!! Lay a thin piece of flat metal down on a piece of wood. Put a piece of steel rod across the metal plate. Hit the rod with a hammer and look what happened to each end of the metal plate. It pinched in. Like a bearing would do in detonation scrapping all the oil off the crank or rod throw before killing the engine. If aluminum rods prevented this, everyone would run them. You can compress an aluminum rod and it will spring back, since when? Amazing. Like a spring? Guess how you determine the cycle life of an aluminum rod? Hint, look in your wallet.