Custom cut aluminum pistons

So im looking at 6061 aluminun for pistons aswell, any thought on this for a daily?

Did research amd decided not to
 
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Tbone3366 said:
So im looking at 6061 aluminun for pistons aswell, any thought on this for a daily?

Did research amd decided not to
Click to expand...
You mentioned 7075
Heat treated 7075 has the highest tensile strength of the aluminum alloys - 83,000 psi
It also has the highest Brinell Hardness – 150
It doesn't machine as well as 6061
It is expensive.

The 4032 alloy is already used for street driven pistons with tight piston to cylinder wall clearances.
The high silicon content controls thermal expansion for tighter clearances and gives it hardness.
It offers a lower cost.

Heat treated 2618 alloy machines very well.
It has a high tensile strength
It operates at high temps up to 575 F.
It is very malleable.
We reduce the thermal expansion for tighter cylinder wall clearances and increase the hardness by hard anodizing the pistons.
We have tried almost every piston skirt coating available, and they all failed under high stress.
Hard Anodizing has had the best results.
It also eliminated the piston ring Microwelding problem we were having.
 
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I can get a bulk deal on the 4032, i will look at 2618 and see what can be done for anodizing

I just got my new tools in for the ring lands and just waiting on a router bit for the inside of the piston to arrive
pmuller9 said:
You mentioned 7075
Heat treated 7075 has the highest tensile strength of the aluminum alloys - 83,000 psi
It also has the highest Brinell Hardness – 150
It doesn't machine as well as 6061
It is expensive.

The 4032 alloy is already used for street driven pistons with tight piston to cylinder wall clearances.
The high silicon content controls thermal expansion for tighter clearances and gives it hardness.
It offers a lower cost.

Heat treated 2618 alloy machines very well.
It has a high tensile strength
It operates at high temps up to 575 F.
It is very malleable.
We reduce the thermal expansion for tighter cylinder wall clearances and increase the hardness by hard anodizing the pistons.
We have tried almost every piston skirt coating available, and they all failed under high stress.
Hard Anodizing has had the best results.
It also eliminated the piston ring Microwelding problem we were having.
Click to expand...
 
Thats what i eas thinking especially with the the deal im getting, at 287 bucks for the 4.250 by 5 inch round bar,
 
pmuller9 said:
At that price, what will you spend on material for 6 pistons?
Click to expand...
The cost of the 6 billets total is 287.14 after tax, for all 6 holes, for the coating i havent found an answer yet, likely have it anodized like you brought up

Should cost around 400 bucks for all 6 holes to be completed and another 50 or so for the rings
 
The anodizing is for the alloys that have a greater expansion rate than the 4032 alloy and for heavily boosted engines.
It will not be necessary for 4032 alloy pistons in a N/A engine.
 
hodaka100 said:
I'm not sure what your goals are but what about just cutting holes in the side of the block and making a 300 2-stroke.
Click to expand...
That's one of the top five most absurd things in the thread.
But barely.

It would require mechanical positive displacement aspiration since there's a common crankcase. Detroit 51 series didn't like ANY exhaust restriction though. A deflector top design crossflow, adds piston weight and complexity, but is relatively clean and efficient at moderate steady state cruise. Use one of each of the pairs cam lobes to push the direct injectors? I have 1957 60ci and 1973 99ci Mercury inline six two strokes I can measure and scale up the port timings so it'll run from 1000-4000
 
Firepower354 said:
That's one of the top five most absurd things in the thread.
But barely.

It would require mechanical positive displacement aspiration since there's a common crankcase. Detroit 51 series didn't like ANY exhaust restriction though. A deflector top design crossflow, adds piston weight and complexity, but is relatively clean and efficient at moderate steady state cruise. Use one of each of the pairs cam lobes to push the direct injectors? I have 1957 60ci and 1973 99ci Mercury inline six two strokes I can measure and scale up the port timings so it'll run from 1000-4000
Click to expand...
I thought about a 2 stroke design but steered clear since a whole new block design and the blower being necessary to run right but would be cool!
 
Tbone3366 said:
The cost of the 6 billets total is 287.14 after tax, for all 6 holes.
Click to expand...
If you use 7” rods the piston CH will be 1” meaning the piston won’t be much more than 2” high.
You may be able to get 2 pistons out of one 5” long billet round.
 
6.7/1.3-ish seems less problematic, still improves R/S to 1.68.

UEM Pistons

uempistons.com uempistons.com

If the head wasn't 2 holes too short, and .050 too much bore spacing, dropping on Raptor top end would be the shortcut to this theoretical reproduction of essentially the same thing.
 
Firepower354 said:
If the head wasn't 2 holes too short, and .050 too much bore spacing, dropping on Raptor top end would be the shortcut to this theoretical reproduction of essentially the same thing.
Click to expand...
It's interesting that the 7.3 Godzilla shares the same 4.530" bore spacing as the 6.2
 
pmuller9 said:
If you use 7” rods the piston CH will be 1” meaning the piston won’t be much more than 2” high.
You may be able to get 2 pistons out of one 5” long billet round.
Click to expand...
I would have to really take things slowly, would be really tight but also the improved rod ratio would help with the sidewall loading
 
pmuller9 said:
It's interesting that the 7.3 Godzilla shares the same 4.530" bore spacing as the 6.2
Click to expand...
Tooling is expensive. Only .310 for two non-thrust cylinder walls and a coolant passage, product of modern casting accuracy.
Shorter than expected rods, for a near 4" stroke, but great heads don't mind as much. 1.320 ch like a lot of newer "big" engines.
Pushrod angle issues, like the very similar DI LT engines. But if OP is making fresh blocks, the cam could be set farther out
 
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