NISSAN RB26DETT ENGINES FOR SALE NO FURTHER A MYSTERY

k20a2/ k20a3 blocks Is there any key dif. in between these two. I'm speaking just the blocks. As in would a K20a2 block be a more sensible choice in sleeving more than the A3? The A3 are so inexpensive to return by so I just wished to know.If your engine is defective, JDM Alliance LLC. will either send out a substitute engine or challenge a refund