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Old 02-17-2009, 12:07 AM
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mattnin
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Default RE: Another brushless 'myth', lower KV = more torque

Well I want to thank Access and this thread for inspiring me to get a motor dyno. There is a saying, "there is a fine line between hobby and insanity" and I believe I crossed the insanity threshold a long time ago :P Actually, I got a really great deal on an old brushed motor dyno that I will have to convert over to work with brushless, and I am very confident I can do so.

So here soon enough and since this will be a modified dyno, I will be able to do testing on 540 size can motors up to 40,000 rpms and 5S Lipo voltage limit. If I ever come across any 3S-5S systems, I will test them out. However, I am really interested in testing peak power and torque values for the stock brushless motors, namely the Novak 13.5 vs. the Hacker 13.5 vs. Orion et. al and using a Tekin RS Pro speed control that has adjustable timing.

This will be complementing my already vast collection of professional RC racing gear, although I suck at racing haha, but getting better! I am still 1st in points series in offroad stock truck this season by pure luck though It seems that weekly I get accused of having a mod motor in stock because there is no one hands down faster than me on the straights, but I am doing a lot of little tricks to my truck such as giving it perfect 50/50 side to side weight balance and perfect crossweight balance and tire balance. And having a dyno so I can gear to peak power is gonna make me that much faster I hope Yea they all used to laugh at me when I was there trying to tweak the perfect cross-weight (I am the only one that does it) and balance my tires. Supposedly it was said they go out of balance every race but they stay surprisingly in balance week to week.

Here is my list of insanity gear so you racing freaks can drool over :P
1 text book "Race Car Vehicle Dynamics" by M&M (this book is used to teach F1 Engineers at Purdue)
1 custom made tweak board with 4 scales

1 TI-89 graphing calculator with a custom program that calculates crossweight percentage, crossweight difference, Left to Right CG position, Left to Right CG difference, Front to Back CG percentage, Total Weight
1 tire balancer
Lots of gear oil and time making everything smooth
Pretty much copying Cavalieri's LIPO T4 setup (I really did modify some settings, I swear!)
1 Novak Sentry Data Logger. This is a particular valuable tool. I am currently using it to make a G-G diagram, and I was just taught how to make a "Total G vs Time" diagram which will be what I start doing based on this weeks races

This graph shows the actual data I logged during the last point series race where I won by half a lap, although it was a close race up until the last 45 seconds and then he wrecked twice right in a row and I think he got caught up a little in some lap traffic, damn close race though and everybody hootin and hollerin made me real nervous on the stands

1 custom stick radio, notice the throttle and steering sticks are swapped


And soon, 1 motor dyno :-) Stay tuned to my posts for the latest!