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Finally got everything apart to replace my intake gaskets. The reason I am replacing the gaskets is when I built the engine 12 years ago I blocked off the intake ports that allow exhaust heat to the carb, thereby keeping the paint on the intake intact. Less than 8000 miles later the block offs deteriorated enough to start burning paint off the intake. After removing the intake today I saw that the block-off gaskets were completely gone. I don't want to do this job every 8000 miles.

Is there a ready-made gasket set that has the block-offs built in, that would also fit the early V8 (265)? I have a gasket set in my hands and it has built-in block offs, but the intake ports on the gaskets are way bigger that the 265head ports, and I understand this can potentially cause a vacuum leak.

Or does anybody have a more permanent solution? Surely this problem has been addressed by folks way smarter than me.
 

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I have a Weiand aluminum intake that has the cross over in it and it was conducting so much heat into my carb that it was vaporizing the gas when I would pull in the garage and park. I bought a gasket with the thin sheet metal block offs and didn't like it, so I bought a good gasket that was solid in the crossover area. It was about 1/16" thick. I took a piece of stainless shim stock that was .030" thick and cut two block off plates. I marked where they went on the gasket and took a Rotozip that has the router end attachment and "milled" out the gasket about half way through so the block offs were flush with the gasket surface. I milled the side that goes against the head. I put a tiny drop of silicone gasket sealer just to hold them in place.

I also very carefully cut two pieces of 1/8" aluminum and made blocking plugs that fit into the intake opening and made them so tight they had to be lightly driven in place. Not sure if they have stayed stuck though with the heating expansion of the intake.

I put it back together and so far so good, but probably only 5-600 miles since then. That was definitely the largest source of gas smell stinking up the garage.
 

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Finally got everything apart to replace my intake gaskets. The reason I am replacing the gaskets is when I built the engine 12 years ago I blocked off the intake ports that allow exhaust heat to the carb, thereby keeping the paint on the intake intact. Less than 8000 miles later the block offs deteriorated enough to start burning paint off the intake. After removing the intake today I saw that the block-off gaskets were completely gone. I don't want to do this job every 8000 miles.

Is there a ready-made gasket set that has the block-offs built in, that would also fit the early V8 (265)? I have a gasket set in my hands and it has built-in block offs, but the intake ports on the gaskets are way bigger that the 265head ports, and I understand this can potentially cause a vacuum leak.

Or does anybody have a more permanent solution? Surely this problem has been addressed by folks way smarter than me.
YES Mr, gasket #100 will work , finding a original is hard to locate now days :)
 

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What gasket did you use last time?

The Mr. Gasket #100, 101, etc. use a piece of sheet metal to block the hole. It doesn't seem like that sheet metal could corrode and get a hole in it but I suppose it's possible.

If I remember correctly, the high performance Fel Pro gaskets simply don't have a hole punched for the crossover. But again, I would think that would last longer than yours.

So lacking a better plan, I'd just try a different style of gasket than last time.

Way back when, I had a set of heads from a well known head porting shop that had the crossovers filled with aluminum. They melted down old pistons and just poured the molten aluminum in the crossover. But you'd have to do that with the head unassembled and off the car.
 
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