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My dilemma, I am going to need to block the heat passage from the heads to the intake. I have 906 heads and an RPM intake (on a 400ci), whats the best way to block the riser, should I cut a thin piece of metal and sandwich it in the bathtub gasket, or should I fill the head or intake passage with something? I am leaning toward filling the intake, but I'm not sure what to use that would stand up to the heat.
 

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[]{} It' a good part and works every time. Willie
 

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Does anyone have a Picture of this Heat Block Off Gasket ???  I asked this same question a few weeks ago and got the same answers. Still Not 100% sure what to do !!!  The Pan that I have Looks like the heat block off pan that everyone sells. Same one at Summit http://store.summitracing.com/partdetail.asp?part=DCC-4286825&autoview=sku   I always thought the heat block off pan blocked that small hole in the center. My intake manifold does not have a passage there   #^~! I was just looking at the add again, I think they are talking about the Hot oil in the valley ???
 

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The more expensive (read: permanent) route would be to have somebody weld plugs into the heat crossover passage in the manifold. It is fairly simple you just need a TIG welder to do it or somebody who's really good with a MIG to do it. I've seen the 1214 breast plate gaskets eat a hole through the block off in the "gasket" before. It does work, but not on a permanent basis.
 

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The jb will eventually seperate from the cast iron due to expansion/contraction difference. This is why I stuff the hole, and I mean stuff with flat punch and hammer, and pour jb on top. High temp epoxy may be a better choice, but haven'y tried it yet. The foil and jb always gets the job done for me.
 

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jacks62440 said:
Does anyone have a Picture of this Heat Block Off Gasket ???  I asked this same question a few weeks ago and got the same answers. Still Not 100% sure what to do !!!  The Pan that I have Looks like the heat block off pan that everyone sells. Same one at Summit http://store.summitracing.com/partdetail.asp?part=DCC-4286825&autoview=sku   I always thought the heat block off pan blocked that small hole in the center. My intake manifold does not have a passage there   #^~!     I was just looking at the add again, I think they are talking about the Hot oil in the valley ???
That is not a felpro PERFORMANCE pan. it is a standard felpor pan ... the 1214 pan has no hole for the heat riser to the intake
 

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Well it looks like I have the stock pan. All you Guy's that are blocking the heat crossover. Are you doing this just for Racing or Just trying to Squeeze every bit you can get out of it for Your Street Car ??? How much of a difference will it make ???  My car, If I ever get it finished will most likely be a Fair weather Street car with limited strip time. I am just Not Sure if it would be Worth it for me    #^~!
 

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I recently had the same problem.

I filled the cavity with silicon glue and then put a 1.00mm steel cap in each end.

Silicon does not conduct heat wheras everyting else does ie air, aluminium etc etc etc etc!

Good luck!
 

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jacks62440 said:
Well it looks like I have the stock pan. All you Guy's that are blocking the heat crossover. Are you doing this just for Racing or Just trying to Squeeze every bit you can get out of it for Your Street Car ??? How much of a difference will it make ???  My car, If I ever get it finished will most likely be a Fair weather Street car with limited strip time. I am just Not Sure if it would be Worth it for me    #^~!
The heat passage screws up the exhaust flow on two of the ports in addition to heating the manifold so the fuel gets hotter. Great for warm up, not so great for power. Depending on the rest of the combo, it can be worth 10-20HP.
 

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Some good ideas above. I do not know the status of the your engine so these ideas may or may not work. The guy above who mentioned using silicone was a good one. I have used permatex ultra copper on some troublesome exhaust gaskets on my 440 in my truck. Also a misguided friend of mine (he runs pontiacs) melted down some pistons and poured the molten aluminum into his pontiac heads to block off passages. I believe he used a torch to melt the aluminum. He said it worked pretty good. I do not know if that will work for you I have not looked at a mopar head with the intent of pouring molten aluminum into it to block off the heat riser passages. Hope this helps.

Steve
 

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Some Good Ideas here. I think I will try Stuffing the hole with Aluminum Foil and cut out some sort of Non Heat Conducting material and Glue it on top of the Foil with Ultra Copper. Just have to find some Non Heat conducting Material   I wish I had a old carb adapter that I could cut up, maybe a trip to the auto pick a part yard    -0*(
 

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That is not a felpro PERFORMANCE pan. it is a standard felpor pan ... the 1214 pan has no hole for the heat riser to the intake
I used the Block off in the 1970's not once had did it fail. I tore it down often because I raced the Car/motor. However never found a failed Felpr
The heat passage screws up the exhaust flow on two of the ports in addition to heating the manifold so the fuel gets hotter. Great for warm up, not so great for power. Depending on the rest of the combo, it can be worth 10-20HP.
It stops the fuel from boiling in the Carburetor when the car is turned off. So when you open the garage door there is no gas Smell!
 
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