How does that work - it sucks more but consumes little?they didn't rate this one but it's one that racers use and it takes less hp to spin it but it does move alot of air...
Anyone Feel Like Running a Mechanical Fan?
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Depends on how well your car is dialed in - I've run 7.14_ 8 passes in a row (1/8th)
that sounds like some bracket racer type of stuff lol. I didn't even think it was about the car being dialed in, but more about the driver just not doing the same thing 10 times coupled with weather changing, track conditions, af ratios, etc...
but that shows that you know what you're doing.
For the record, the Car Craft comparison test I mentioned did test a rigid 4-blade fan like this one. The result? 473.0 HP output, or 21.4 HP less than the electric fan setup.
For anyone who wants to read the test for themselves, I found a .pdf of the entire issue here:
http://seads.net/performance/images/CarCraft/Car Craft May 2000.pdf
I wish. it's probably more like 50lbs to 100lbs for 1/10 of dead weigh, depending how fast/slow or heavy/light the car is. Even taking off 50lbs of rotating mass from the wheels/tires may only be a 1/10th.
What confuses so many people about dragstrip timeslips is this: your trap speed is a direct indicator of your car's power-to-weight ratio. Your ET is merely an indicator of your traction at that exact power output. Example: you can hook up perfectly and run, say a 13.50 ET on one pass... but on the very next pass with no adjustments you can muff your launch and only run a 14.0 ET. Both trap speeds will be virtually equal. How is that possible? Because your power-to-weight ratio did not change significantly between runs.
I know drag racers like to talk in terms of ET. They'll frequently tell you how a certain mod dropped two or three tenths off their time. However, this is completely misleading at best and flat-out wrong at worst. The next time someone tells you a certain mod dropped two tenths off their quarter mile ET, you can tell them they could have achieved the same result without making that modification but instead shaving a tenth off their 60-foot time. 😉
So to answer your question: trap speed.
Mechanical fans usefulness is long over. Every junkyard has dual electric fan setups for less than $50 and for $10 more you can get a 2 year warranty.
If people want to still live in the stone age, they are welcome do it. Just don't try to drag anyone back to the stone age with you because you think things were somehow better back then. They weren't.
If people want to still live in the stone age, they are welcome do it. Just don't try to drag anyone back to the stone age with you because you think things were somehow better back then. They weren't.
Well that's good to hear. I would hope modern racers aren't relying on such a power robbing device to help them win. Seriously. I'm curious about this new fan--does it flex? Is it rigid? (I ask these questions since it goes along with the topic of this thread.)
If anyone wonders, I do have some drag racing in my background. I spent five years campaigning a turbocharged Dodge Caravan in my local track's bracket racing series. Despite being FWD and having only four pistons underhood, I competed in the Heavy class... meaning I went up against all the domestic RWD V8 cars. It was fun, and it gave me plenty of opportunity to sweat over tenths and even hundredths of a second. Speaking of, have you ever lost a drag race by one thousandth of a second? I have. Twice. It sucks, but that's what serious competition can do to you.
If my car looses a tenth of a second I'm looking for a problem - it's dialed in and I know what it will run when I show up at a track. I have a weather station with lots of data imputed and it will tell me what the car will run w/ the weather conditions. Worst loss 1/10000 of a sec.
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