I have an '84 toyota pickup with a 22R that smokes alot and I was going to do a rebuild on it and I noticed the pistons were stamped .50. It looks like it needs to be bored. I was wondering if it could be bored any more one person told me that it really couldnt be bored anymore because it would get too close to the waterjackets. If it cant be bored then I'd have to buy another block. I was also wondering, if I do have to buy another block, is a 22RE block interchangeable with a 22R block and what is the year range (earliest-latest) of when they used the same blocks. Any help I could get would be great! Thanks!