What trap speed mean in the 1/4 mile?
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Joined: Nov 2002
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From: Riverside CA
Vehicle: 2000 Tib/03 Silverado
What trap speed mean in the 1/4 mile?
What does it mean when both cars trap at 107 mph but one run 12.6 and yet the other run 13.5???
This confused me. Both cars should be equally fast on the highway right since they trap the same speed?
This confused me. Both cars should be equally fast on the highway right since they trap the same speed?
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Joined: May 2001
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From: Upstate NY
Vehicle: 2010 Genesis 2.0T
Assuming drivers of equal competence and cars with similar drag coefficients:
A car with a shorter elapsed time but a lower trap speed has really good acceleration off the line but crappy acceleration once it's up to speed, but since it got a good launch it was still able to run the length of the track quickly even if it couldn't speed up much after it got out of the low gears. So basically it has wide-ratio gears, i.e. really short low gears and really long high gears.
A car with a longer elapsed time but a higher trap speed has crappy acceleration off the line but better acceleration (relative to the first car) once it's up to speed, so while it took a while for it to get up to speed, in the last few yards of the run it was able to accelerate faster than the first car. It probably has close-ratio gears designed primarily for highway driving and/or a crappy turbocharging system that takes forever to spool up so it can't get going fast off the line.
A car with a shorter elapsed time but a lower trap speed has really good acceleration off the line but crappy acceleration once it's up to speed, but since it got a good launch it was still able to run the length of the track quickly even if it couldn't speed up much after it got out of the low gears. So basically it has wide-ratio gears, i.e. really short low gears and really long high gears.
A car with a longer elapsed time but a higher trap speed has crappy acceleration off the line but better acceleration (relative to the first car) once it's up to speed, so while it took a while for it to get up to speed, in the last few yards of the run it was able to accelerate faster than the first car. It probably has close-ratio gears designed primarily for highway driving and/or a crappy turbocharging system that takes forever to spool up so it can't get going fast off the line.
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From: Lacey, WA
Vehicle: Two Accents, Mini, Miata, Van, Outback, and a ZX-6
Or, the worse ET could come from excessive wheelspin.
In similar cars, but one has a great launch because it's AWD and the other fries all of first and second because it has an open diff and FWD you can get pretty major differences in the ET with minor differences in trap speed.
In similar cars, but one has a great launch because it's AWD and the other fries all of first and second because it has an open diff and FWD you can get pretty major differences in the ET with minor differences in trap speed.
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Joined: Oct 2009
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From: Melbourne
Vehicle: Hyundai Excel
Another example mate, my old mans mustang runs 124mp/h across the line at 12.1 seconds.
Cars that are much more suited to drag racing could have a win with a ~105mph run.
All the mustang does is lights them up off the line and gets traction somewhere around the shift into 4th.
Cars that are much more suited to drag racing could have a win with a ~105mph run.
All the mustang does is lights them up off the line and gets traction somewhere around the shift into 4th.
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Last time i had my car on the track my exit speed was 170kph. Which is good for a low-mid 13. But it was raining. Track was and ran a high 14. Watch a ten second fwd its super fast with e exist speed of 220kph. But a rwd can do a ten with a exit speed of under 200. Its all about the launch!