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U.S. Vintage Trans-Am Racing Part 2

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U.S. Vintage Trans-Am Racing Part 2

Old 01-03-2016, 03:10 PM
  #9106  
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not knowing the track or the track size - maybe 99% of the local racers run 1c Oval or 1c 1/12th scale on-road..so they wanted to created a class where the STUFF those guys have could be used in a TC - sounds like a wise business person possibly... w/o knowing MORE INFO!
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Old 01-03-2016, 03:14 PM
  #9107  
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A 1s 17.5 car would be severely imbalanced. You would have to add a lot of weight to get it balanced. I think having that much weight and on a 4wd system would put A LOT of strain on a 1s system.
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Old 01-03-2016, 04:05 PM
  #9108  
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Originally Posted by SWTour View Post
not knowing the track or the track size - maybe 99% of the local racers run 1c Oval or 1c 1/12th scale on-road..so they wanted to created a class where the STUFF those guys have could be used in a TC - sounds like a wise business person possibly... w/o knowing MORE INFO!
Yes, I think this is the case. I wish National rules were a option though. I hate to have to buy specific electronics for one track.
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Old 01-03-2016, 04:05 PM
  #9109  
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1s 17.5 in a heavy VTA car? punch-less and pointless.. I can't imagine having any fun trying that out.
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Old 01-03-2016, 04:46 PM
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Yes, I think this is the case. I wish National rules were a option though. I hate to have to buy specific electronics for one track.
Most tracks/clubs have a policy of "We'll run any class with 3 (or 4) entries" --

Some tracks will combine classes if small numbers of entries - (list them as separate class in computer, so they are scored as their actual class) but combined on track.
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Old 01-03-2016, 04:49 PM
  #9111  
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1s 17.5 in a heavy VTA car? punch-less and pointless.. I can't imagine having any fun trying that out.
NOTE: I am NOT a 1c Fan (not even for pan cars) - but...I doubt a 17.5/1c is gonna be much less punch than a 25.5/2c and it would be a tad bit lighter w/ the 1c.
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Old 01-03-2016, 06:42 PM
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Originally Posted by SWTour View Post
I doubt a 17.5/1c is gonna be much less punch than a 25.5/2c and it would be a tad bit lighter w/ the 1c.
It's going to be a bunch less. The power would be like running 34.5T/2s-- which I don't think exists, unless it's some kind of crawler motor. Really gutless, but really smooth!

I would expect the 17.5T/1s to get some kind of weight reduction to help it compete with 25.5T/2s.
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Old 01-03-2016, 06:54 PM
  #9113  
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I seen some of these 1s/17.5 cars run, they seemed a little bit faster than the 2s/25.5 cars, but after about 4 minutes of running, they faded to the point they seemed to hold the throttle wide open for the entire track, and yes that seems to be a minnesota thing, I personally have no use or desire for this type of class, so if its a big race in my area, I ask what rules they are running and then opt to go race

I also think they where given a weight reduction, so thinking back it was a 1450g car
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Old 01-04-2016, 08:23 AM
  #9114  
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Originally Posted by Brewboy View Post
So...two of my local tracks have VTA rules that have a 17.5 motor and 1s lipo stated. One track requires it and it's a option at the other that follows national rules.
Trying to make a smart purchase decision...can you run a 1s lipo with a 2s esc, or do I need a 1s rated esc?
Curious what everyone else out there is running.
Looks like some options for 1s esc is Hobbywing, Turnigy, Novak. Anything else I should look at? I don't want to spend a ton of money.
Thanks in advance.
Since we're both from Minnesota, here's a write-up I did on 1S-2S ESCs: http://www.meatballracing.com/1s-2s-...d-controllers/ - no explanation necessary.

For the others, the 1S/17.5 class has been running since 2008, before the national standard was set. It's a carryover from 4-cell/27-turn setups that were tried - and apparently well-liked because "light is right." The MN VTA cars have a lower race weight: 1280g http://www.molzermoweryracing.com/product_news.htm My 1S is balanced better than when I occasionally run 2S.

Last edited by jrfoell; 01-04-2016 at 08:32 AM. Reason: Added weight specification
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Old 01-04-2016, 11:45 AM
  #9115  
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Originally Posted by jrfoell View Post
Since we're both from Minnesota, here's a write-up I did on 1S-2S ESCs: http://www.meatballracing.com/1s-2s-...d-controllers/ - no explanation necessary.

For the others, the 1S/17.5 class has been running since 2008, before the national standard was set. It's a carryover from 4-cell/27-turn setups that were tried - and apparently well-liked because "light is right." The MN VTA cars have a lower race weight: 1280g http://www.molzermoweryracing.com/product_news.htm My 1S is balanced better than when I occasionally run 2S.
Thanks! good information here.
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Old 01-04-2016, 12:16 PM
  #9116  
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did you know that the 25.5 motors started out as crawler motors?....and 17.5 motors used to be USVTA legal....with 4 cell, and did you know that 21.5 motors with boosted esc's used to be the normal.....also 4 cell 27t is the closest to what is in play now with 25.5 and lipo....
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Old 01-04-2016, 12:36 PM
  #9117  
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...did you know the original Crawler motor was the 18.5 - and the 17.5, 21.5 AND 25.5 motors were built for my Oval Series along with the ARCOR oval series - looking for a PERFECT "STOCK BRUSHED 4 Cell" Pan Car replacement...

And...NOVAK was the ONLY Brushless company willing to take a chance at Building a SLOWER motor --- even though Bob didn't understand WHY anyone would want to go SLOWER.

(I still have one each of the original R&D motors in each wind)

Also - these motors caused a whole new set of BIG Pinion Gears and SMALL Spur Gears to be built to get the gearing these ultra LOW RPM motors produce.

The 17.5 motor - was the 1st one that NOVAK Built us - and it was TOO FAST using 2 cell in a pan car right off the bat. (Was pretty much equal to a fast 19t, or a slower Modified Motor in an oval car) -- The 21.5 was next, and while it was still TOO FAST for the "STOCK" Speed guy, it was an awesome power combined with a restricted output size 2c lipo (but once the NATION jumped on - they opened the battery rule..and that too became TOO fast for most)

The 17.5 with a 4cell NiMh put out a near perfect "STOCK / 4cell" replacement - but nobody was willing to build a 1c for our needs. (It wasn't until someone in Florida or that region started pushing for 1c that they were built and tested)

When the 25.5's came out - they were USELESS because at that time NOBODY offered a tall enough gearing system to use them... (Top Speed in a pan car w/ 2c and the tallest available gear at that time...was something like 24 mph) -- but with gear companies making bigger gears quickly (Pinions) and smaller Spurs, we were able to get a decent speed from the 25.5s in a pan car...but by then the Pan Car OVAL guys Nationally had made the switch to 1c/17.5 for the "STOCK" speed, and 1c/13.5 for the "AVERAGE JOE" Mid-Range Speed.

We never pursued the 25.5 after that - but I was really happy when I saw the USVTA group grab on to this motor and create a market for it.

Many of us Original "BRUSHLESS" groups have been very loyal to NOVAK - because THEY are the company who had the BALLS to lead the Brushless movement -- EVERYONE ELSE has tried to take it away...w/ better/faster/higher performance products, but NONE were willing to step up and LEAD.

Last edited by SWTour; 01-04-2016 at 12:49 PM.
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Old 01-04-2016, 12:48 PM
  #9118  
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yep...I have an original 25.5 stator too
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Old 01-04-2016, 01:01 PM
  #9119  
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Myron - did you get a Stator (Ballistic style) -- mine are the SS versions -- Ballistic made the NOVAK Motors much nicer. We fried a LOT of SS style 17.5's and 21.5's on our VELODROME pushing them hard w/ Advanced Timing ESCs looking for SPEED.
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Old 01-04-2016, 01:07 PM
  #9120  
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I'm going to bring something up, not to start a crapstorm or to call anyone out, but simply to bring it to light.

At a recent event, I volunteered to do USVTA tech. At tech we measured the usual weight, battery voltage, ride height, etc. But I also had acquired a Fantom Facts Machine 2, which has the ability to measure stator resistances. With a simple 10 second check, it can determine whether or not the NOVAK motor has a 25.5 wind stator in it by measuring the resistance across two motor tabs.

Based on measuring 'known' new, good stators, it should be around 100 milliohms when measured across any two tabs AB, AC, or BC at 77F. Temperature will affect this measurement (about 0.2% per degree of temperature change).

What we found that there ARE Novak stators out there that have a black insert and look like the normal 25.5 stators but are NOT 25.5 winds. Some of the Crawler stators have lower winds, such as 18.5T and 21.5T. Which will create a huge performance advantage.

By measuring the stator resistance, I was able to detect a couple of non-compliant stators at the event. One was the 18.5T crawler stator. It measured at 50 milliohms when measured across two motor tabs. A 17.5 motor will measure at around 42 milliohms. So it was quite evident that it was non-compliant. Needless to say, that particular car was quite a bit faster (TQ in fact) and was DQ'd.

It's this motor stator:

http://www.amazon.com/Novak-Ballisti.../dp/B002SWTF18

The point of this post?

If you're putting on an event and you're serious about checking motors, you need to tech stator resistance. You can't simply look at the stator insert to tech it. But what you need is an ohm-meter capable of accurately measuring milliohms. Normal ohm-meters cannot measure at this level. The Fantom Facts Machine 2 is one such device, but is out of production. A cheaper option is the VICI VC480C:

http://www.amazon.com/Vici-Vc480c-Ac.../dp/B0090Y3W5W

Still not cheap at around $100, but any track should have this in tech, IMHO.

Just thought I'd throw that out there. I've been racing USVTA for two years now and it wasn't until I bought the Fantom Facts Machine 2 (for my own motor building/testing purposes) that it dawned on me what was going on.

With the proper meter, you can check stator resistance in less than 10 seconds in tech, it's non-invasive and can be done with the motor assembled and attached to the ESC. Just unplug the battery first. The readings are unaffected by the ESC motor leads.

Mark
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