69mach1build 22 Report post Posted July 1, 2016 High performance motor with 4.1inch stroke, aluminum heads, that will see <5,000mi/year. Has anyone done this to a 1969 block and how did it fare? 1 sherriepl3 reacted to this Quote Share this post Link to post Share on other sites
barnett468 418 Report post Posted July 1, 2016 you can if the cylinder walls are not rusty inside the water jackets but it is far better to go smaller if possible . it is also safest to have it sonic checked first . if it has a core shift, it might have problems at .060". Quote Share this post Link to post Share on other sites
Rsmach1 71 Report post Posted July 1, 2016 +1, For performance use .060 over is pushing it with any stock sbf block. Ideally .030 is max, the most I would go is .040 and only if it all checks good. This is not to say it hasn't been done, you just have to know going in with higher hp/torque levels, really bad things can happen... Quote Share this post Link to post Share on other sites
Hoover 12 Report post Posted July 1, 2016 When I had my small block rebuilt, it was already at .030 over. My rebuilder bored it to .040 over, and mentioned that if it didn't pan out we would have needed another block. He was concerned about overheating. So have it sonic checked as barnett468 suggested. Quote Share this post Link to post Share on other sites
Max Power 74 Report post Posted July 2, 2016 I am running 60over but I had it sonic checked. Quote Share this post Link to post Share on other sites
