Filling the block then bored out

T

Tbone3366

Famous Member
If i filled the block with aluminum used in making an aluminum cylinder head, then tapped coolant passages, what would be the largest bore i could safely run i know 4.08 is about the largest anyone should go, just this has been running through my head
 
If you Sonic check the block you would know much you can go.
 
Is filling a block with molten aluminum a good option? Or what is the usual filling material?
Aluminum will shrink as it solidifies and will expand more than the iron on engine warm up cycles.
 
hodaka100 said:
Is filling a block with molten aluminum a good option? Or what is the usual filling material?
Aluminum will shrink as it solidifies and will expand more than the iron on engine warm up cycles.
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The block fill must not shrink or expand during the curing period.
Its coefficient of thermal expansion needs to be identical to the cast iron engine block.
It needs to have good vibration dampening, and heat dissipation.

Hard Blok is one of the more popular block fillers.
 
Tbone3366 said:
I saw a post about a filled block hemi 300 that was bored 4.125 so i was curious what the safest over bore would be with a semi block fill with coolant passages
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As bubba posted, the block would need to be sonic tested for cylinder wall thickness.
A block that has significant core shift during the casting process will have thin cylinder walls in places.

In a high performance application, the cylinder walls crack above the block fill line so the block would need to be completely filled.
A completely filled block with coolant running just through the head would probably not run cool enough for street use.
It would work well for drag racing especially with ethanol and methanol fuels.
 
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pmuller9 said:
As bubba posted, the block would need to be sonic tested for cylinder wall thickness.
A block that has significant core shift during the casting process will have thin cylinder walls in places.

In a high performance application, the cylinder walls crack above the block fill line so the block would need to be completely filled.
A completely filled block with coolant running just through the head would probably not run cool enough for street use.
It would work well for drag racing especially with ethanol and methanol fuels.
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Ok, this gives me a better idea of what to look for in doing work, do you think it would be possible to press in some copper tubes that go to the base of the water jacket and fill the block all the way up with it upside down and that way theres a small channel for coolant and allows water to flow into the head for normal cooling too? Would i need to draw a diagram to better explain what im thinking
 
My best guess is that wouldn't work very well since there would be no real circulation unless all the coolant passage were also connected together to each other at the bottom of the block too.
 
bubba22349 said:
My best guess is that wouldn't work very well since there would be no real circulation unless all the coolant passage were also connected together to each other at the bottom of the block too.
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Thats what i was meaning, with a small gap at the base of the water jacket to allow coolant to flow up to the head
 
Darton should be able to come up with an interlocking sleeve set that would allow 4.250 and leave the fill level down 2-3" for some cooling.

The dimensional instability of aluminum, and paper thin factory sleeve columns, is a recipe for failure.

The commercially available block fillers are popular, because they work. If re-melted turkey pot pie tins was a good idea,,,

Steel shot mixed with the cement type fillers, or an epoxy, would add a bit of dampening, I'd suspect.

But, if a big power E85 inliner is the goal, the CNG Cummins should live at 1000hp
 
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