rod/stroke ratio for the stock H23A is 1.49:1 ideally, you want to be as close to 1.75:1 as possible. it's the "perfect" compromise between revvability and torque.

you can have custom rods made that are longer than stock, and have custom pistons made with relocated wrist pin holes to use the rods without the piston ringpack going above the block's deck. the most you could get to would be about 1.53:1 before the wrist pin placement on the piston interferes with oil ring seating.

you can also add material to the deck of the block, essentially making it taller so you dont need to use relocated wrist pins on the pistons... you can use standard wrist pin location with rods as long as you want depending on how much taller you make the deck. then you simply deck the block flat, stuff it, and let her rip. JG Engine Dynamics has done this for CR/VTEC setups to give it a better rod ratio while maintaining the added displacement.

essentially, there's ways around it, but it's all on how much you want to spend. in this case, if you have to ask how much, you probably cant afford it.