puting tubes in cylinder heads?

[saltracer1]

I admit I have never heard of this before. this guy seems to port the heck out of these heads and when he breaks through he adds tubes through the heads and epoxies over the hole.

https://www.youtube.com/watch?v=xsU4kWOGzrw

[Dynoroom]

Been doing it for years. First saw it in 1984....

[maj]

Very common here in the 80's on the Holden (think GM)  6 cyl , either remove the big chunk of cast iron and replace it with a tube or put a shaped aluminium casting in and pin it with the tube  depending on if you were running a big single carb or tripple side drafts and wanted individual runners all the way to the valve

[dw230]

My father did that in the 50s.

DW

[Milwaukee Midget]

Similarly on the BMC heads, and other shared-port inline heads, although it's the hole that the pushrod passes through, not the head stud.  

With the BMCs, bad habits developed in the 1960's are hard to break, and people continue to do it that way because they've always done it that way.

The sad part is that's not where the big flow restriction is.

[fordboy628]

Been doing serious head & block modifications with epoxy for since the late 1970's . . . . .

Using the right product is the trick . . . . .

[Kiwi Paul]

I`d be interested to know what that product is, Mark....