SM Head Modifications on a budget
Here's a couple of before pictures of the head bolt bulge. Minimum width at the bulge is 1.264". Sonic tester shows 0.145" aluminum thickness at the bottom of the bulge and 0.160" at the top of the port. Don't know if the brass tube insert messes with the sonic reading.
Here's a couple of before pictures of the head bolt bulge. Minimum width at the bulge is 1.264". Sonic tester shows 0.145" aluminum thickness at the bottom of the bulge and 0.160" at the top of the port. Don't know if the brass tube insert messes with the sonic reading.