That dyno is messed up. Mustang dyno's are one of the lower reading dyno's, should be around 290hp for a Nismo. Perhaps they were using the wrong gear? Either that or they tinkered with the dyno to give higher numbers to their customers and make them feel better.

:iagree:

Sorry if im late but howcome all the mags I read and all the vids i watched when the Nismo launched claim the Nismo puts out 350hp stock.They basically lied to everyone? I had feeling it wasn't what they said it was too. This car felt restricted when I test drove it.Now i feel stupid that they had me telling ppl my car put out 350hp.

You weren't lied to, you just don't understand how hp can be measured. The Nismo puts out 350hp at the crank but only about 290hp to the wheels. The way car companies measure hp is at the crank, basically the advertised hp that every company uses. Hp measured at the wheels is the crank hp that is left over after going through the drivetrain. Due to friction and other forces hp is decreased as it goes through the clutch/flywheel, tranny, driveshaft, differential and eventually to the wheels. I'm not going to get too detailed, just do a google search for wheel hp vs. crank hp.

:iagree:
He is right!

Ohhh.. ok. Thankyou for that information. So the differance is usually 60 vs the two on our cars. Not all cars are the same either then depending if they are fr ff awd? For example a GTR claims 507hp and when dyno'd it came out to 430hp thats a 77hp differance to the wheels.

The usually assumption with HP loss is 10-15% depending on the drivetrain.
Better cars usually have less loss so the number is closer to the flywheel but never the same.