In every issue of Car & Driver, when they list performance numbers they have 0-60 time and also 'street start 5-60' time. The street start time is always .5 to 1 second higher than the 0-60 time. Would the 1/4 mile times be a lot worse also? I thought starting at a roll would be an advantage, why isn't it? Does this mean if you are at a stop light race you are better off sitting still until you can launch?

 

maybe they start in 2nd gear

 

I always wondered this too. Maybe it has to do with the RPMS being different because your going 5 MPH

 

I think its because with A/T cars 5-60 mph they don't brake torque and with M/T cars the clutch is let out fully and there is no optimization of launch revs.

 

In a manual gearbox, the clutch is fully engaged, and there is no advantage that you'd gain from a higher-rpm clutch engagement. In an automatic, it's the same, except the torque convertor is already transmitting power to the wheels, so no "flashing" will occur.
5-60 mph is more realistic for real world comparisons. How many races will you ever have on the street from a standing start with wheels/tires a blazin'. Most will be from a slow roll like when first pulling away from a light. 5-60 also puts more emphasis on the engines power delivery and not as much on driver skill.

 

I thought it might have something to do with a regular 0-60 being a high RPM clutch drop, still I thought rolling would be an advantage.

So I guess cars with more low end power or broader powerband would not suffer as badly on a street start? Just found the street start time for a 95 Max, 0-60 6.7, 5-60 7.2, the times are even better after 40,000 miles. Seems pretty good compared to the tests of sport compacts in the past two issues of C&D, most of those cars lost over 1/2 second in the street start. I like my chances in a stoplight race.
http://www.caranddriver.com/xp/Caran...lass=44&page=3

 

Its in the launch.

 

What would happen if i was rolling at 5mph then i decided to step on the clutch rev it to 4k and then engage the clutch again.Is this still not a legitimate way to do it?