... assuming the same driver is shifting at the same shifts points ... and in a straight line?

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Steven

Automatic. The computer takes away the human error.

 I switched from my '07 C6 w/auto to an '08 w/manual, and the automatic couldn't compare with the jump of the 6-speed when popping the clutch at about 3500rpm. Yes, if you think that you're prone to making human errors, get the slush-box instead. But for me, the enjoyment factor alone of the 6-speed vs. the automatic is 300 percent greater.
Another reason I went to the 6-speed, besides it giving me greater control, is the awkward and possibly dangerous delays that can occur when the automatic downshifts, e.g. like when needed entering a freeway from the on-ramp. It was embarrassing almost getting rear-ended because I had to wait for the automatic to decide what gear it wanted to be in. 

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2008 C6 Coupe, LS3, Blk/Blk, 6M Z51, 3LT

I used the specifications for a 2007 C6 to take a look at this question, because those were the specs I had at hand. Aside from the transmissions, the cars still won't be identical. That's because the final drive ratio with the 6L80-E automatic transmission is 2.56 to 1, while the ratio with a six speed manual is 3.42 to 1.

Transmission gear ratios are considerably different too.  On the automatic first thru sixth have ratios of 4.02, 2.36, 1.53, 1.15, 0.85 and 0.67 to 1. The standard six speed manual has ratios of 2.66, 1.78, 1.30, 1.00, 0.74, and 0.50 to 1. With the Z51 performance package the six speed manual's ratios are 2.97, 2.07, 1.43, 1.00, 0.74, and 0.50 to 1. The axle ratios help to even things out however. tgstoner2010-08-31 11:24:54

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Tom Stoner

I have had 3 2010 GS Convertibles.  first one stick- best pass  12.98@113 mph. second one auto-best pass 12.86@111 mph. Now have Callaway Supercharged GS Convertible-auto- best pass 11.43@125 mph.  The stick is fun but cant beat(very often) a automatic at the drag strip. The Callaway is a BEAST!!!

New best in the Callaway today--11.27@126.36 mph

This is running in stock form-no air out of the tires-NO SLICKS!

Another new best- 11.23

New best MPH in the Callaway- 127.89

Last time at the strip- a pair of 11.01s on street tires with the Callaway.  ZR1 doesnt do that off the showroom floor.

I forgot to mention, I have touch-control (forget the actual name) shifter in my 2002 MB ... which enables me to upshift or downshift by touching the shift knob (on the console).  This technology is now often found in many other late model vehicles.  Unfortunately, while it is clutchless, it clearly does not have the same precision as a manual shifter.

With regard to taking out the human error (paddle shift vs. manual), let's remember that a car with paddle-shift does NOT necessarily mean the driver has the most (or best) experience ... so ... if a driver were to engage 2nd gear at 1,100 RPM's, or 7,000 RPM's ... (you understand the idea), there IS human error.  The paddle shift does not shift FOR you, just as a powerglide race transmission does not automatically shift for you either.

Lastly, though slightly off-topic, the ability for a driver to manually control the clutch can be a powerful driving tool.

Enjoy!


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Steven