if you wanna know what they are running just take a look at the rules for whichever class the cars are running.
H4 class is pretty much a stock engine with some bolt ons.
H1 class is for swaps, B16's, B18's, B20's, K20's etc. you are allowed to do lots of things in H1, but your limited to stock OEM parts short block, and stock intake mani and tb. other then that you can pretty much do whatever you want. H1 cars put down anywhere from 200-230hp. cant wait to have my H1 crx on the track

(need to get it on the track in the first place, and build up to H1, but my engine is built to H1 specs)