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Old 11-28-2007, 12:17 PM   #16
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That's exactly what we did (guinnie pigs) in ALL the classes. the only thing we didn't test was the whole lipo thing. we were really hesitant due to the hazards that apply when lipo's are abused. But we didn't have much to stand on when the IB's were exploding left and right so we allowed them (lipo's) however we do require that they are charged in a LIPO sack. We also havn't purchased any IB's anymore had have only purchased EP's and we will also purchase the new cells enerG cells from promatch. (we are a Promatch dealer - www.promatchracing.com )
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Old 11-28-2007, 12:23 PM   #17
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I guess there should be a charging sack in every pit now regardless of what type battery you run that should be the rule so lipos and nimh don't get mad at each other !!
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Old 11-28-2007, 12:29 PM   #18
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as a seller of lipo-sacks.. I don't have a problem with that. I'm not sure taht I wouldn't get shot by some of our racers though.
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Old 11-28-2007, 04:44 PM   #19
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That's exactly what we did (guinnie pigs) in ALL the classes. the only thing we didn't test was the whole lipo thing. we were really hesitant due to the hazards that apply when lipo's are abused. But we didn't have much to stand on when the IB's were exploding left and right so we allowed them (lipo's) however we do require that they are charged in a LIPO sack. We also havn't purchased any IB's anymore had have only purchased EP's and we will also purchase the new cells enerG cells from promatch. (we are a Promatch dealer - www.promatchracing.com )
LOL. Its like de ja vu. Same exact thing here, except for the IB problems.
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Old 11-28-2007, 05:30 PM   #20
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last night on a big track a brushed guy with lipo beat a 13.5 with nimh so they are close closer than a 17.5 and stock

watched the 17.5 class at a brl race and they are not much more than a 21st century 540 silver can motor

just my .02 cents
A 13.5 motor is almost always .2-.3 a lap better vs. a stock motor in the same car when geared correctly.

The guy with the 13.5 and NIMH should have put a whipping on the brush motor, not to mention NIMH is usually faster than lipos up front anyway.
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Old 11-28-2007, 08:55 PM   #21
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not to mention NIMH is usually faster than lipos up front anyway.
LIPOS have a higher peak amp rating, and the voltage doesn't drop (or as severely) when a load is on the battery pack. they are also lighter.

I don't see how they are faster? I must be missing something?
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Old 11-29-2007, 06:02 AM   #22
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watched the 17.5 class at a brl race and they are not much more than a 21st century 540 silver can motor

just my .02 cents
maybe on oval. I use a 17.5 aginst 13.5's on a weekly basis with good results. Granted its not oval, where .5 secs means the diff between TQ and c main, but I dont see no "21st century silver can" power here
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Old 11-29-2007, 06:12 AM   #23
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17.5 vs. silver can.

Yeah, from our expierience, a silver can is MUCH slower then a 17.5. We have a "novice" 12th scale class and they use the silver can. It's the exact same rules at the stock 12th (wich we allow the 17.5 to run in) and the silver can is WAY slower. If they want, they can invest in the 21.5 motor and run in that class, but we tell the guys it's not worth the investment as we don't have any other class running the 21.5 and the silver cans we sell for 7 bucks. 7 bucks for say 1/2 season or so to get used to 12th, learn to drive/setup vs. 85$ for a 21.5 is a no brainer.
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Old 11-29-2007, 06:32 AM   #24
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LIPOS have a higher peak amp rating, and the voltage doesn't drop (or as severely) when a load is on the battery pack. they are also lighter.

I don't see how they are faster? I must be missing something?
I believe the NiMh is faster initially, High Peak amp draw is only relevant IF the motor pulls it, stock and 19T don't come close to sucking the current out of a NiMh. NiMh do seem to have a higher peak voltage...if you make it to the start buzzer with a warm pack your should have more speed in the opening laps, trade-off will be the possibility of tapering toward the end.

As for weight, except for the Losi T/C it becomes a drawback since you still need a balanced car for roadcourse and I'm seeing guys adding 3-4 sticks of lead.

That said I think for the sport racer the LiPo's are easier since they can stay in the car, be recharged over and over, provide more run time, not need to be replaced when punch dies off like a NiMh. (the beginner would not need to replace NiMh packs as much since driving is really more of an issue than speed)
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Old 11-29-2007, 06:57 AM   #25
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I've been running the 13.5 for since before they were availble to the public.During that time I've run against the brushed 27 turn motors and been getting beat by them regularly.However more and more of my fellow drivers are switching or have switched to the 13.5 Novak motor with the sintered rotors. In TC the fast guys in 27 are still faster than the Bl guys.I've heard in Oval the 13.5 is to fast and they are trying both the 17.5 and 21.5.Different applications and different motors for stock performance in this classes.For 2008 our series (FSEARA) is staying with the 13.5/27 class in all stock and Master class racing.We are also going Lipos in hard cases. Looking foward to our first race in Jan 19th-20th.
Actually a warm-up race for me to test the lipos running 8 minute qualifiers with a 13.5 motor is this coming sunday in Orlando. Fun is just 3 days away.
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Old 11-29-2007, 07:06 AM   #26
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I think were getting a LOT of good feedback on this thread. Only thing I'd like to see more of, is guys that are comparing one to the other, what size track? We've had a couple people mention (james35) that the track size matters. I've mentioned that our track is fairly small, 36x60. while a mod motor may reach a slightly higher speed down the straight...it doesn't get it in the infield, so 90% of our classes are stock (or 13.5, 17.5 for 12th) etc.
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Old 11-29-2007, 07:48 AM   #27
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If i am not mistaken, lipos have lower internal resistance, therefore are able to deliver the power to the motors when they need it at the rate they want.
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Old 11-29-2007, 12:06 PM   #28
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You are absolutely right. The 13.5 is not even close to a stock motor. Average racers think that they are comperable to a brushed stock because they can now run close to the lap times of a good brushed stock racer when in reality if you give the good racer a 13.5 he'll be at least a lap faster with the brushless over the stock brushed. The 17.5 is not really the answer either. It is a little bit slower than a fast stock but still closer to a stock than a 13.5. The answer may be something like a 15.5.


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they are no where close in either class. the 13.5 has way more punch out of the corners and way more top end. The are closer to an average 19turn. I think most track has the same 13.5/stock 27turn class. they are the closest you can get at this point. but I guarantee you that you get an average to above average racer running a 13.5 and the "fast" guy run the 27t, and it will be a very close race.
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Old 11-29-2007, 12:24 PM   #29
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The 17.5 is not really the answer either. It is a little bit slower than a fast stock but still closer to a stock than a 13.5. The answer may be something like a 15.5.
I haven't done any 17.5 testing yet, but we are about to. I've heard that a 17.5 can be a little faster than a 27T. This would make sense to me because the 18.5 produces 119 watts of power. Novak hasn't updated their chart in a while, but it would stand to reason that the 17.5 probably produces around 135 watts of power. Since a 27T produces 130 Watts of power at best, the 17.5 should be really close.
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Old 11-29-2007, 12:28 PM   #30
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I'm really curious about ALL the facts. You say "not even close" well, what's close? Isn't it a "relative" term based on several different variables?

Last year, in our stadium truck class. I ran a brushed axiom motor..this year, LRP 13.5 w/sintered rotor. Lap times (after playing with gearing are the same). when I went too many teeth higher, the motor just got way to hot..so when I got the motor where it handled good, stayed in that 150 range and wasn't a slug down the straight, overall, the times stayed the same as last year.

Now, again, our track size is small, 36x60, approx 192' drive line. that's small compared to a larger flowing track that they have at the bigger races. I certainly wouldn't argue that the 13.5 CAN be faster on a large track, but I'm curious to what your track size is so were comparing apples to applles.

Attached is one of the layouts we use. To race TC's and 12ths we remove the jumps..same drive length. The laptimes for 12th and TC are in the 8 second range, while the offroad times are in the 11 -12 second range. .5 - 1 second on our track is LOT, however .5 to 1 sec on a large track..isn't very much.

I also think a track like ours does not allow the faster motors to really open up and take advantage of their speed..which Is why the different types of motors are CLOSE at our track. Maybe not the same, but close enough to keep the guys happy...and basically...as a track owner...that's what it's about, keeping the racers happy and having a good time.

I think eventually, it probably won't matter. Brushlesss will be come the norm and the classes will be broken up into wattages or wind types (13.5 10.5 etc) and we won't have to worry about..what's comparable with a brushed motor..but for now, were flexible.
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Novak 13.5 vs. 27t brushed motor-track-8.jpg  
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