Filling blocks

[MichaelThompson]

Hey guys just a thought experiment at this point. I have a couple Ford Flathead blocks that are not going to be practical street engines. One has a significant void in the exhaust port and the other has been bored a full .250” with a full relief in the decks. It has one cylinder sleeve.

I’m thinking the big bore block would make a cool starting point for a dragster engine.

The question is can you fill the block with aluminum or some other material that would stay in place and also serve as a medium in which one could drill into and thread some key head bolts deep into the block?

I was also thinking that if the block is poured full you could actually insert copper pipes that are ported to the front or sides of the block to provide some cooling if necessary.

I know , I know crazy ideas but like I said just a thought experiment at this point. But someday that big bore engine will be in the que and I’d like to do something cool with it.

[ClassAct]

Hey guys just a thought experiment at this point. I have a couple Ford Flathead blocks that are not going to be practical street engines. One has a significant void in the exhaust port and the other has been bored a full .250” with a full relief in the decks. It has one cylinder sleeve.

I’m thinking the big bore block would make a cool starting point for a dragster engine.

The question is can you fill the block with aluminum or some other material that would stay in place and also serve as a medium in which one could drill into and thread some key head bolts deep into the block?

I was also thinking that if the block is poured full you could actually insert copper pipes that are ported to the front or sides of the block to provide some cooling if necessary.

I know , I know crazy ideas but like I said just a thought experiment at this point. But someday that big bore engine will be in the que and I’d like to do something cool with it.

If you fill it with aluminum all you do is add weight. The aluminum shrinks.

[MichaelThompson]

Gotcha thanks. I guess that kills the idea of melting the dozens of used pistons I have laying on my shelves.

Back in the 70’s I heard of people using Devcon. Is that something to think about?

Maybe mix the epoxy with cast iron powder?

[bunker]

Back in the 80's I did a lot of work for a tractor pulling outfit, they filled their blocks with some type of cement. No idea if they added epoxy or other types of binders, never saw them do it, just did the block work.

[BillK]

We used to do a few of them each year and always used Hard Block. But you wouldn't be able to drill and tap it. It is like a concrete.

[Ks Fats]

Rick Schnell (?) filled his blocks with aluminum but with a bore that's + .250 there is going to be some movement. Having never done it I "suspect" there would have to be a pre & post heat involved moving things even more. Epoxy might be the best alternative but getting everything clean in the water jackets might be tough. Seems like pdq 67 used to talk about some type of furnace or refractory cement that worked well, maybe a search might reveal something.

[Diodedog]

Halco machine grout is what you want

[MichaelThompson]

Thanks guys this give me an idea on where to start with my big bore engine.

[PackardV8]

FWIW, BTDTNA sixty years ago. We tried boring out the cylinders of a flathead V8, sleeving, filling the block and it was so wonky, we line honed, decked, bored, honed, but could never keep it square.

[MichaelThompson]

I’d like to know more about that Jack. Are you saying you bored the cylinders completely out of the block?

I can certainly understand how things could get wonky because the cylinders really are the main structure in those blocks.

My goal really is to just make this engine useful. It’s an 8BA block so there is precious little deck surface between the end cylinders and a couple water passages.

On a Packard straight 8 I’m working on there is a copper “sprinkler” pipe that runs the length of the block.

This gave me the idea that I could sort of plumb the insides of the water jackets with copper tube to circulate some water to the cylinder heads. Maybe not even necessary for 1/8 mile drag runs.

I was actually thinking that if the aluminum was a viable idea it might even be hard to get to operating temps for a short run.

All just in my mind at this point but like I said sometime soon I’m going to tackle this.

I have the block and pistons and most of the other stuff to get it running so not much to lose.

[PackardV8]

FWIW, on a racing engine, consider running alcohol. We've been told some running at Bonneville can make the 5-mile run with a solid block, no coolant. Some run coolant in the heads, some run solid heads.

[Walter R. Malik]

Hey guys just a thought experiment at this point. I have a couple Ford Flathead blocks that are not going to be practical street engines. One has a significant void in the exhaust port and the other has been bored a full .250” with a full relief in the decks. It has one cylinder sleeve.

I’m thinking the big bore block would make a cool starting point for a dragster engine.

The question is can you fill the block with aluminum or some other material that would stay in place and also serve as a medium in which one could drill into and thread some key head bolts deep into the block?

I was also thinking that if the block is poured full you could actually insert copper pipes that are ported to the front or sides of the block to provide some cooling if necessary.

I know , I know crazy ideas but like I said just a thought experiment at this point. But someday that big bore engine will be in the que and I’d like to do something cool with it.

Steel DEVCON could work but, it would be awfully expensive...

[frnkeore]

Some of the limitations your working with are:

Bore centers are 4.000 on the end cyl and 5.124, between the center cyl.

The bosses for the bolt/stud are .68 deep but, the deck, is only .25 thick overall. You don't deck FH's unless you have to.

I couldn't find the diameter of the bolt bosses but, in the Ford dwg, but they look like they have enough diameter to take a good size tread insert. You could also do a 1/2 x 13, stepped to 7/16 stud or just use 1/2 x 13 studs and drill the heads but, tq to 7/16 spec.

You could use a wet type sleeve, that would finish to 3.438/3.50 bore, with a 4" flange x 1/8 thick and a OD of 3.75 (1/8-5/32 walls) and then furnace brase it into the block.

[HemiJoel]

RokBlock is the stuff to fill with, no shrinkage, adheres well. I agree with Packard V8, run alky. No need to cool the block for 1/4 mile.

https://www.competitionproducts.com/Rok ... tinfo/ROK/

[PackardV8]

You could use a wet type sleeve, that would finish to 3.438/3.50 bore, with a 4" flange x 1/8 thick and a OD of 3.75 (1/8-5/32 walls) and then furnace brase it into the block.

Seen it tried twice, but never seen anyone able to seal all eight sleeves top and bottom; there were always leaks.