Is it easier to go fast when outside temps are higher, if you are more traction limited than power limited (motorbike)?
Talking about 260mph and beyond speeds, is there a meaningful difference in attainable speeds at 60 degF vs. 90 degF?
Land speed, temp effect to aero
Moderator: Team
Re: Land speed, temp effect to aero
You know . . . . , Smokey Yunick (sp??) tried painting his NASCAR Chevelle (and maybe others) black. His thinking was the hotter surface would allow the air molecules at the surface to be hotter, and therefore more active, and let the air go over it with less drag.
Smart Guy!!!
Take care, K
Smart Guy!!!
Take care, K
Re: Land speed, temp effect to aero
The bike in question is black already.
Just trying to iterate if it would make sense to attempt new record in warmer climate...
Standing mile is an acceleration contest, so our guys should have something to gain from more tire as well.
Just trying to iterate if it would make sense to attempt new record in warmer climate...
Standing mile is an acceleration contest, so our guys should have something to gain from more tire as well.
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Re: Land speed, temp effect to aero
Probably a conundrum?
The hotter air may make it go through it faster, but the hotter air would make the HP output less.
So, the amount HP lost that it would take to propel the vehicle may be more than the amount gained going through the air?
The hotter air may make it go through it faster, but the hotter air would make the HP output less.
So, the amount HP lost that it would take to propel the vehicle may be more than the amount gained going through the air?
John Wallace
Pontiac Power RULES !
www.wallaceracing.com
Pontiac Power RULES !
www.wallaceracing.com
Re: Land speed, temp effect to aero
Assuming the bike is supercharged you want the lowest air density and the best surface condition for traction. The density altitude is generally between 4000 and 8500 ft. but the surface condition varies all over the place. The afternoon will generally have the highest DA but can bring water to the surface if it under the track. If you stand on top of a trailer you can see it at times moving around. The two biggest things are a proprly tuned suspension and if faired eliminating lift. I have thought the swing arm for one track might be completley wrong for another, pavement vs salt.
A high DA will reduce aero loads but if the track surface goes away it does not matter. As a side note the fastest cars generally run the big numbers late in the afternoon. If you are running a SCTA-BNI meet you are stuck with return runs in the morning so making a couple of early morning passes might be instructive but if an FIA/FIM meet you get an hour to turn around and complete the return run so the conditions will be very close to the down run.
A high DA will reduce aero loads but if the track surface goes away it does not matter. As a side note the fastest cars generally run the big numbers late in the afternoon. If you are running a SCTA-BNI meet you are stuck with return runs in the morning so making a couple of early morning passes might be instructive but if an FIA/FIM meet you get an hour to turn around and complete the return run so the conditions will be very close to the down run.
Re: Land speed, temp effect to aero
Thank you for sharing your experience! Sounds like DA is definitely something to keep in mind.
The bike is turbocharged running alky.
http://www.youtube.com/watch?v=2QGL_L2WoNA
The bike is turbocharged running alky.
http://www.youtube.com/watch?v=2QGL_L2WoNA