I think it would be a good idea to build this engine if it were the same block as all B's...The B's all have same bore's but with diffrent strokes, just like the D-series, or any Honda engine series in that case... so, i think this means that the engine have a lesser stroke from the factory... so let's assume all the assembly were the same ass all B's in the B15 block except the crank... that means that you have about 1.5 mm to add to the connecting rod length to achive a rod/stroke ratio of 1.76, not bad... so considering you wanted to push it so you fitted custom pistons with a compression height of 25 mm, then this gives you a chance to make a custom rod length of 139.5 which translates to an R/S ratio of 1.81!!! but will you setup the engine good to run with that R/S ratio or not? that's the question.