2010 Mercedes Benz SL65 AMG Black Series Hits the Dyno

December 24, 2008
0812 02 Z+2010 Mercedes Benz Sl65 Amg Black Series+front Three Quarter View
It costs $100,000 more than a regular SL65 AMG, so buyers of the 2010 Mercedes-Benz SL65 AMG Black Series had better get a little somethin' for their money. And they do-with carbon-fiber body panels, a fixed roof, and styling that makes the Black Series look as though it's an escapee from a DTM race.
We covered the Black Series in depth here, but Mercedes asked us not to perform instrumented tests on it during our initial drive. Tech editor Don Sherman is suspicious that the Black Series' quoted 3.6-second 0-60 mph time is a little ambitious given that the lighter (by half a ton) but similarly powerful Corvette ZR1 hits 60 in the same amount of time.
0812 03 Z+2010 Mercedes Benz Sl65 Amg Black Series+front View
The truth of the matter is that with a twin-turbocharged torque monster of a V-12 under the hood of the Black Series, 0-60 numbers are less about power than they are about the launch. The Black Series can (and will happily) spin its tires at any point up to 60 mph, so the result of any off-the-line timed run speaks more about available traction than it does about grunt.
To that end, we took a Black Series to a chassis dyno to see what kind of power, exactly, it puts down. We were also looking forward to see the shape of the curve. AMG fitted the 6.0-liter V-12 with larger turbos to help maintain boost at higher engine speeds. If the engineers have done their job well, we should see big gains at the top of the rev range.
0812 04 Z+2010 Mercedes Benz Sl65 Amg Black Series+engine View
But the first thing everyone asks: "What did it put down." Answer: 573 hp @ 5300 rpm and 682 lb-ft @ 3620 rpm in third gear. That's wheel horsepower, remember. And the result is right where it should be given the engine's rating of 651 hp @ 5400 rpm and 738 lb-ft @ 2200 - 4200 rpm.
0812 08 Z+2010 Mercedes Benz Sl65 Amg Black Series+dyno Graph
Unlike the previous 6.5-liter V-12 car we tested, the S65 AMG, the Black Series' transmission will remain faithfully in whatever gear you select, so we were able to measure its output from just over idle all the way to redline. We did the test in fourth gear, and the resulting increase in the length of the dyno test meant the turbos had a bit longer to spool up. That resulted in 715 lb-ft @ 3400 rpm, but any benefit was eliminated at the top of the rev range, when the additional friction of the rear wheels-spinning at 190 mph-caused a slight drop in wheel horsepower.
Last year's S65 AMG, which is rated at 612 hp and the same 738 lb-ft of torque, put down 36 fewer horsepower and 61 less lb-ft of torque. [Click here for that story.]While it seems that the peak numbers aren't much higher-especially on a percentage basis-the Black Series' bigger turbos make an enormous difference at the top of the rev range. Indeed this is where output matters most-flat out, low-end torque is irrelevant once you're moving along in first gear.
0812 07 Z+2010 Mercedes Benz Sl65 Amg Black Series+dyno Graph Vs S65
The comparison chart (below) clearly shows massive gains at high rpms. Nearing 5500 rpm, where the S65's turbos were all out of steam and the transmission forced a shift, the Black Series engine puts out more than 100 hp and 100 lb-ft more than the S65's did.
So no matter what the 0-60 numbers look like for the SL65 AMG Black Series, remember that they're more a function of grip than power. The dyno doesn't lie-the lucky few who can afford a Black Series are getting a V-12 with a much broader power band than those who settle for the regular 604-hp SL65 AMG. Those poor souls.
Click the link below for video of the SL65 AMG Black Series' gauges during the run.


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