Getting more out of this engine is not easy. Getting another 79 wheel horsepower and 58 pound-feet of torque at the wheels on 91 octane is downright incredible.
Let's take a look at the tune only numbers first. The completely stock SLS Black Series put down 521 horsepower to the wheels. This is a drivetrain loss of 17.3% which is about right where a rear wheel drive dual (wet) clutch transmission car should be using conventional drivetrain loss thinking.
After Weistec's tuning output rises to 549 wheel horsepower. This is mostly due to a torque increases from 4500 rpm to redline so power is being picked up on the top end. This is a good illustration in torque multiplication with revs as a peak gain of 11 wheel torque translates to an additional 28 peak horsepower at the wheels toward redline:
Now, the addition of the long tube headers changes the torque curve dramatically. Torque gains are now seen throughout the entire curve not just from 4500 on. This makes for a fatter powerband and it is almost surprising how much room AMG left on the table for a good set of long tube headers. Peak torque increases but just under 60 pound-feet to 463 pound-feet at the wheels for a dramatic increase over the standard 405 pound-feet at the wheels:
The end result is 600 wheel horsepower, naturally aspirated, from a 6.2 liter V8 on 91 octane pump gas. To put this in context the 5.7 liter V10 out of the Carrera GT does not put out this much power. Neither does the Ferrari V12 used in the Enzo. This is just shy of 100 wheel horsepower per liter and to get this level of specific output with more rotating mass than smaller six and four cylinder motors is rarified air. AMG did a hell of a job on this motor.
Weisec's SLS Black Series tune retails for $2100.00. Get it here: http://www.weistec.com/m159bsna.html