Why not just get a 340? Or bore a 318. Lots will go to 4 inch bore. Ive had them bored to 4.04 to use standard bore 340 pistons. That was long b4 anyone even thought of checking the bores. Kim
Not many 318’s will go to a 4.00. When ever the question is asked, how far is to far, what can it do for an overbore, my answer is always the same, a sonic check will tell you what’s what.