Shifting Gears: Rule change going into Pocono Raceway

11 Jun

At the halfway point of the Sprint Cup Series regular season, NASCAR teams competing at Pocono Raceway – known as the “Tricky Triangle” – will test the impact of new freedom they’ve been given when it comes to transmission gear ratios. In the realm of gear ratios, whether you want one that is higher (1.1:1 as opposed to 1.5:1) or lower (1.7:1 as opposed to 1.4:1) depends on what kind of track you’re running.

A lower gear ratio allows for more acceleration. This is what comes in handy when you want to put the pedal to the metal as the stoplight turns green. Or, if you drive a race car for a living, more acceleration is what you want during a restart. It’s also helpful when you’re on short tracks, when you’re constantly slowing down to turn and then speeding back up on the straightaways. The drawback to the increase in torque that comes with a lower gear ratio, however, is worse fuel economy and a lower top-end speed. The latter isn’t as much of an issue on a short track, but fuel economy is always an issue, and it certainly has been prominent in the sport lately.

A higher gear ratio, on the other hand, gives you a higher top speed and better fuel economy. You want this kind of setup on superspeedways like Daytona, where you’ve got extensive straightaways and time to get all the way up to your max speed.

Keeping those things in mind, here’s the official rule change from NASCAR, and further down is the Sprint Cup Series Director John Darby on how this relates specifically to Pocono.

More Shifting Now Available At Pocono: Gear Ratio Changes
For practice, qualifying and the race, all competitors must compete with transmission gear ratios as follows: 1st gear optional; 2nd gear 1.70:1 or greater (1.699 or less will not be permitted); 3rd gear 1.14:1 or greater (1.139 or less will not be permitted); 4th gear must remain 1.00:1. Overdrive ratios will not be permitted.
This is an addendum to the 2011 NASCAR Sprint Cup Series Rule Book which states: Transmission gear ratios between 1.00:1 and 1.28:1 will not be permitted for the remaining forward transmission gears except road course Events. Overdrive gears will not be permitted.
“There has been some confusion that shifting was not allowed at Pocono, and that isn’t true. The real reason shifting stopped at Pocono was because gear ratios weren’t compatible for shifting. Over the last few years, teams have done it with limited success but not on a consistent basis.
So, what we did was change transmission gear ratios to make it easier on engines and give teams a better opportunity to use third gear and shift. Primarily it’s in an effort to allow the drivers to maximize the RPM on each of the three straightaways.
When you look at the race track, you instantly see the issue that they’re faced with. The frontstretch is more than 3,700 feet [3,740], the backstretch or the Long Pond Straight is 3,000 [3,055] feet and the short straightaway between the Tunnel Turn and Turn 3 is only 1,780 feet. So consequently [there will be] a straightaway that you don’t get anywhere near your maximum potential RPM. This is all done in an effort to try to even those three straightaways out in the RPM that the engine will attain.”
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