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10-20-2016, 02:49 PM | #21 | |
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Re: Launch RPM
Quote:
The clutch control on the above car is functionally similar to what i have supplied to many Coyote Stock and Factory Stock racers. The slip i posted earlier is from one of those guys... Grant Last edited by weedburner; 10-20-2016 at 03:36 PM. |
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10-20-2016, 06:03 PM | #22 |
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Re: Launch RPM
Here's a simplified example of why you want to keep average rpm as high as practically possible-
Lets say a car gains rpm at an average rate of 6k per second in 1st gear. Let's also have the clutch lock up .5 sec into the run with the tires remaining dead hooked. If it is launched at 6k, tires are stuck, and the clutch locks up at .5 sec, rpm is going to get pulled down to 3k by .5 sec into the run. From .5 to 1.0 seconds it climbs from 3k back up to 6k, regaining the lost rpm. What all this boils down to is that during the initial 1 second after launch, the engine's average rpm was 4500 rpm, which means the engine made 75 revolutions over that 1st second of the run. Now suppose that same car launches at 6k, but the clutch slips just enough that the engine does not lose any rpm over that same 1 sec period. Now the engine's average rpm was 6000, which means it made 100 revolutions during that initial 1 second period. Both leave from the same rpm, but the launch that didn't lose any rpm actually packs 33% more revolutions of WOT power production into the same 1 second time period. Last edited by weedburner; 10-20-2016 at 06:59 PM. |
10-20-2016, 08:32 PM | #23 |
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Re: Launch RPM
Pretty cool! How much rpm does it spike the tires on the gear changes? Sounds fun. Any video? Thanks, Jim
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James Schaechter 3163 STK |
10-20-2016, 08:52 PM | #24 |
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Re: Launch RPM
About 500 less than you would expect from the ratio change.
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10-20-2016, 10:34 PM | #25 |
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Re: Launch RPM
Typically, in a our stocker we see a 200-300 rpm spike of driveshaft rpm at each gear change.
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James Schaechter 3163 STK |
10-20-2016, 10:34 PM | #26 | |
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Re: Launch RPM
Quote:
Your are right on the money with the SLR. The .3 definitely drags the engine rpm down Sean
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Sean Marconette 84 Mustang 5060 SS/N |
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10-21-2016, 01:49 AM | #27 | |
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Re: Launch RPM
Quote:
If you are clutchless it can still help you launch higher, but you will still need an adjustable/centrifugal to get some slip on the shifts. Grant |
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10-21-2016, 05:37 AM | #28 |
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Re: Launch RPM
I went to your link. You have done some really cool and well done modifications there. I see how you get the radials to work as well. In our world, the tradeoff is not likely to benefit us, compared to what we are able to legally run, but I can see where it is better for your combo. Well done!
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James Schaechter 3163 STK |
10-21-2016, 08:53 AM | #29 | |
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Re: Launch RPM
Quote:
x2!!!!! Very nice work, Grant. Definitely outside the box thinking. Super cool little car. Must be ridiculously fun. Kevin |
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