It is accurate enough to get you in the ball park area so long as the inputs are correct and you can fill all of them out and know what your doing. Exhaust pipe size is an excellent example.
The other problem here is the people here commenting on it. Some good, many not, read the instructions and then, THEN remember that this dyno sim is really no different from a rel world dyno.
Now your all saying WTF is this Fish TALKING ABOUT?!?! OMG!
Well, if my engine makes 435 on the sim, the. I go down the block to dyno room "A" and it dyno's 450 on a real dyno , the program sucks!
If I go down to dyno room "B" and it dyno's 415, the dyno sim sucks and the other actual dyno is generous / broken / out of tune etc... Whatever.
I go back to dyno room "A" and the tell me dyno room "B" is stingy, they suck!
I go to dyno room "C" and it kicks out...
Get the picture on bench or real racing dyno's yet?