I'm a bit skeptical of the ad I saw for an SSR on ebay that stated the car has 640hp.
It it possible?
Bca8ball claims well over 600 hp from his daily driver which I wouldn't doubt at all. I think that was crank hp not wheel, I didn't read the ebay listing.
It's the same play on words Chevy used when advertising our SSRs at 390hp for the automatics and 400hp for the 6 speeds. It actually isn't as much of a play on words as it is that they are on an engine dyno and they are talking about the LS2 engine vs the actual vehicle.
Their HP rating are at the Crank (CHP) vs Rear Wheel (RWHP)
The automatic at 390 CHP = 325 RWHP
The 6 speeds are 400 CHP = 342 RWHP
In reverse if a dyno measures your RWHP at 522 you add the same percentages to equate it to CHP.
522 RWHP = 619hp at the crank
My 522 RWHP is at only 8lbs of boost, there is actually more available with different size supercharger pulleys for more boost and a more aggressive tune.
I'm cammed (with upgraded rocker arms, springs, and push rods), headers with 3" dual exhaust to the rear.
However, mine is a daily driver, I enjoy tinkering and tuning but I'm not racing it so I see no reason to attempt to squeeze more out of it.
Here is a good reference: