Steam holes huh?

[LilRedBronco]

I may be way off base here but I think the edlebrock heads already have the holes. They want you to drill the block to match.

Sorry guys long day at work... I was able to look at the block and old heads when I got home just now. The old heads and the block appear to have had the holes brazed over during the last rebuilt and the more modern 302 style holes bored in there.

At first I was puzzled as to how my supposedly original 302 was not to spec so to speak.

Upon closer inspection it looks like someone did a fairly masterful job of brazing/welding over the steam holes on both the block and the heads and then making the holes like they are on the more modern 302s. I don't remember the cut off but the Edelbrock sheet gives the year they converted to the new style.

All the aftermarket heads I looked at from TFS, AirFlow and Edelbrock have "NO" in the spec sheet next to the words- Steam Holes: NO.

So it looks like my block and heads originally came with the steam holes but the machine shop corrected it to be like the more modern blocks. Interesting

 

[JIMS74]

I have the edelbrock heads on my 302, and had to drill the steam holes in the block. I marked the area to be drilled using the gaskets, then center punched where marked, and drilled with a new 1/8" drill bit, I placed a strong mag. base next to the hole while drilling to try and keep chips out of the water jackets of the block. material is not real thick did not take long to make break through at all. good luck, I was a little nervous drilling into the block. double check your instructions and locations and go for it.
Jim

 

[blubuckaroo]

http://www.theengineshop.com/product_images/product_pdf-pdf_file-169.pdf
These instructions came with my Windsor Jr heads.
Instructions that come with stuff are important. You can't blame the manufacturer for problems like overheating if you didn't read the literature.