2004-2007 Cadillac CTS-V Performance Mods Discussion, Hit the dyno today... in Cadillac CTS-V Series Forum - 2004 - 2007; first pull - 322.7rwhp 316.2sae (torque)
second pull - 332.3rwhp 324.1sae
bone stock with 514 miles
voila, I'll scan the ...
350 for a z06 compared to a CTS which is allegedly only 5hp less...but has different airflow etc, I've heard people say the thing dynos at 315-330 typically (on this board) so I don't know what to expect. I beat 330 at least!
Take a look for yourself. It's actually a trailer so they take it around to shows with them. Only thing that sucks is you can't use it in the rain, since it's open-topped. I have some photos of the car on it, will post those in a couple days.
For those of you new to dynos (like I was) a tip the guy gave me to get the best pull is to make a run, then let it cool 15-20 minutes and go again. As you can see he picked up 10hp doing that.
So you're making 390hp at the flywheel, 10 less than advertised. It's not too bad I guess.
Converting wheel HP to flywheel HP is nowhere near an exact science.
From what I've seen, a lot of big-motor cars also are cooling-limited on dynos; it's almost impossible to get enough airflow through the radiator and engine compartment to get a dyno measurement that corresponds to real-world on-road HP.
Yes, it may be worth noting he didn't have the fan on for the first pull. The fan was one of those small plastic jobs, pushes a decent amount of air, but as you said nowhere near what you get full on at 80+ mph.
I'm loading mileage on the car so we'll see how she performs as we go.
Interesting article in the latest issue of Car & Driver on dyno testing. In short, they are quite unreliable, especially those that do not use a high powered fan; and your HP numbers can change dramatically depending on which dyno you use. I bet you could gain a few HPs if you had a big fan blowing on you.