My friends,
dont' be confused. I am talking about a 15% "error" for a chassis dyno. I do not have one, but that is what the chassis dyno people / engine builder use (here in Germany) to tell you to give the car owner a better feeling = "more" horsepower.
We, no my buddy, dynos his engines on an engine dyno before he puts the engine into the car.
That serves for the run-in procedure, as well as to verify that the engine runs correct. As a side effect he optimizes the torque curve and measures that. That takes about 2 days most of the time.
His cars / engines, mainly race engines, wander to the races and nothing would be more frustrating than having a leaking engine 1000 miles away from home.
As you said before, the chassis dyno is a good tuning tool, better than doing it on the street. Especially when you're not allowed to travel much beyond 60 mph. And it shouln't be 15% off! Go there!
800 hp = crap, indeed.
My buddy's 520 + cui almost reaches that values, but we are talking big money here.
No, I am not posting a picture from his Can-Am McLaren again.
Only if you insist.
No, I am not Mr. Dyno or Mr. Engine in our forum. I built about 10 to 15 engines (one all-aluminum, three times) and five Cobras and watched the rest.
Don't be mad with me, but I always hated that "four-hundred and yadda yadda horses talk".
BTW, my car had 552 Hp. That has been calculated by the coast down / accelerating method described elsewhere. GM over here does it all the time on the Autobahn with big engined cars.
This car went like h***, just ask the big-bikes in my neighborhood. And it had more potential. Lift was only 0.600" at the valve.
Dominik