Curt B. provided all the data you need if there is not a 261 gasket available when it is convenient to drill the holes in the 848. Here is a photo of
a stock 261 gasket on a Bob Toros head. The photographs in the May 55 HRM issue show the additional water circulation holes in the 261 head, but no mention of the need to drill the holes in the 235 head is made in the text. Did McGurk not notice this? When I built by first 261 with a 235 head in 1958 I did not notice the missing holes either. I did not have any unusual overheating problems that I recall. I did drill the holes for my next 261 in 1960 after I realized that the holes were there for a good reason.
Hoyt
