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Hemi partially filled block

smithchargers

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Has anyone here ran a 426 Hemi engine that has had the water jackets partially filled on the street? If so did you experience overheating?
 
Sounds like you found a block (well priced) that you hope can handle street duty???
Do you know what was used to fill it? Some times they used epoxy back in the day - which believe it or not, can be burned out. Need really hot industrial ovens and an operator that will put up with all the smoke and stink! Was it cast after '71?
 
I need to find out a little more info. I am getting mixed reviews on this topic so far.
 
I think he was asking what HP will you build the motor too. Higher compression, bigger cam, more heat. If building a stock motor for a street car you should be ok if level is below freeze plugs. Sometimes this was done because the notched the inside of the block for a stroker crank and needed the clearance. It could open a hole to the water jacket. So filling the bottom sealed the block besides stiffening.

I have a MP block done like that.
 
Ok. It is below freeze plugs and drain valve on side of block is still functional
 
Only if you want to run alcohol, and lots of it for street use. That was an old trick back when racers only option was using a stock block. They ran alcohol for cylinder cooling and a filled block would have benefit of added bore strength to the bores so you could bore the block a little further than if not filled. Only a run 1/4 mile and done situation. Alcohol is a great fuel for keeping an a engine cool. That’s why only drag cars run it. It cost way more than gasoline and burns at twice the rate. These days you would buy a race prepped block from the aftermarket all machined and completely designed for race use only.
 
Have and still do. Bought it that way about a yr ago. Block was windowed. No problems so far with block. Has a big oil cooler which from what I’ve read is important. Running a Mancini monster radiator. T stat is a 160. And a big 7 blade fan with short clutch. Motor put out about 500 on dyno so it’s not super built. Thinking exhaust valve guides and seals are shot though as it smokes over 3000 rpm bursts or long trips on the highway. Mines more for a driver. New blocks aren’t that much if your really worried about it. Stuff isn’t cheap. If u have no other parts besides block I’d consider a crate. But to answer your question will be fine with block filled and not overheating.

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Only if you want to run alcohol, and lots of it for street use. That was an old trick back when racers only option was using a stock block. They ran alcohol for cylinder cooling and a filled block would have benefit of added bore strength to the bores so you could bore the block a little further than if not filled. Only a run 1/4 mile and done situation. Alcohol is a great fuel for keeping an a engine cool. That’s why only drag cars run it. It cost way more than gasoline and burns at twice the rate. These days you would buy a race prepped block from the aftermarket all machined and completely designed for race use only.
It is not a dry block. It is still a wet block and is only partially filled
 
Have and still do. Bought it that way about a yr ago. Block was windowed. No problems so far with block. Has a big oil cooler which from what I’ve read is important. Running a Mancini monster radiator. T stat is a 160. And a big 7 blade fan with short clutch. Motor put out about 500 on dyno so it’s not super built. Thinking exhaust valve guides and seals are shot though as it smokes over 3000 rpm bursts or long trips on the highway. Mines more for a driver. New blocks aren’t that much if your really worried about it. Stuff isn’t cheap. If u have no other parts besides block I’d consider a crate. But to answer your question will be fine with block filled and not overheating.

View attachment 836358
What you have is what I want to put together. What temp does it usually run?
 
Sitting in traffic then overheat alley at the Syracuse nats it never went over 200. Stop and go for prob half hr. Was close to 90 later in the day with lots of humidity. Block will be fine. Mines std bore. Normal driving btwn 170-190. Is it just the block your buying?
 
Sitting in traffic then overheat alley at the Syracuse nats it never went over 200. Stop and go for prob half hr. Was close to 90 later in the day with lots of humidity. Block will be fine. Mines std bore. Normal driving btwn 170-190. Is it just the block your buying?
No. Most of the components are there. Block is pretty nice. Heads need some work.
 
If your not familiar with hemis might be good to have some one experienced look at it. Once you get it, make sure you get the block and heads pressure tested besides, magnifluxed. Lot of little things can pop up with old race blocks that you might not catch at first.
 
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