I don't want to take this thread too far off topic but the K20A2 is the swap engine of choice as it comes with the 6 speed manual, plus higher hp, plus tons of aftermarket support, ie. Hondata, K-Tuned, etc. The K20A3 is the base engine for the Acura RSX and comes with the 5 speed. More plentiful, but not as desirable as a swap, hence the premium price for the A2 motor. If you are going to go through all of the effort and cost to do it, most people want the most bang for the buck, so to speak. The K24 is not a performance engine, as I understand it, but for those that really want to go for broke, you can do a "Franken motor" which uses a K24 block with the K20A2 head. Tim Hoover is doing one of his swaps with a Franken motor that was built for him. See his current thread.