If the engine is rated at say...190 like the H22A, will all that go to the wheels of the cars its being dropped in? If not, what does that depend on. A H22A being dropped into a 94-97 accord I mean.

 

you will loose between 15% and 23% depending upon driveline and accessories

 

Engine horsepower rateings were standardized years ago due to manufacturers playing games with the numbers for advertising purposes. We are now left with what's called SAE* Net Brake Horsepower.
This is measured at the crankshaft with the engine burdened with the accessories it will see in the car. In effect, it's the horsepower value that will be (in the real world) transfered to the transmission.
What happens after that (transmission gearing, chassis rolling resistance etc) will determine what horsepower remains at the wheels.

P

* Society of Automotive Engineers

 

i've seen h22 swaps dyno as low as 155whp and as high as 190whp.

only way you can know for sure what your motor is getting is to get it dyno'd