Rollout vs ET

I don't have specific numbers, but since quicker and consistent RT's win more races than faster ET's, I always focused on the RT's. However, I have staged shallower than normal and other changes for a few heads-up races over the years.

Nibbling away for better RT's is similar to trying to take 100 lbs out of a car to gain a tenth in ET. (i.e.: take 1 lb out of 100 locations.) Physics guarantees an improvement, but it's not obvious till you start adding up the 1 lbs. Carb response, converter, traction, suspension tuning, staging/launch rpms, etc. are all factors. But there are more! Higher tire pressures (within reason), solid motor mounts, poly trans mounts, aluminum spring eye bushings, frame connectors and properly triangulated roll bar/cage also help. The less WASTED movement there is (flex, twist, mount compression, etc.), the more efficient the car will be at moving it forward. *****A note on the tires - more air pressure actually raises the tire off the ground showing less distance front-to-back at the photocell level, so it leaves the beams quicker. On the flip side, a tire with lower pressure, flat as an extreme example, provides more distance from front-to-back at the photocell level, so it takes a little longer to leave the beams. I know some people who actually vary their rear tire pressure for more or less wrinkle (wasted motion), but without compromising traction. Air pressure is a good fine tuning aid.

Also, it's best to do your comparisons at the same track. RT's can vary due to the track! Different timing systems, slight photocell height variations, track wear and rubber build-up can all make minor differences. There are tracks that can have .05 or more differences compared to other tracks. Some even have a few hundredths between lanes.....at the same track! Lots of variables to be aware of.