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Head Swap 403 To 350 #7 Heads

Tonyf

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Hi, folks Thanks for your acceptance.

I got 79 403 with a mild cam, aluminum intake, and headers installed when I bought it.

I bought some 350 #7 heads. What’s involved in swapping them out.

I am going to take them to the machine shop.

What should be done to the heads?

2.00 or 2.07, I’ve heard either one would work but some chamber relief.

One thread said the 2,07 kept breaking.

Someone said something about water holes in the 403 was Siamese, and the 350 would to be drilled to get better cooling.
 
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