I know the power ratings are only about 10 HP difference from the factory, and that the A2 is the VTEC engine. Are the gains worth swaping one for the other? I have one of each, both are good, not sure if it's worth the time to swap or not. How bad is the wiring? Just a simple ECU swap?

 

engine harness, ecu and key reflash. if you have them or can get them cheap, go for it. otherwise you'll see more gains from dropping the A2 head on the A1 block and running a vtec controller. take it from me. im running what i call a D17A1.5 because im running a stock A1 block and an A2 head with the EGR deleted and manage it all with a hondata kpro, so i wired the vtec, vtec pressure like stock and converted my primary o2 sensor to a wideband primary AFR sensor based on the HX or 04-05 civic wiring.

 

Look in the FAQ's before posting next time: https://honda-tech.com/forums/showthread.php?t=2247386