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I'm new to the 4 cell Stock oval racing scene. Used to race 6 cell stock. I've tried my motor setups from 6 cell stock in 4 cell stock and to be honest with you...I'm going nowhere with this class....

What brushes/springs work really well??? What kinda tweaks littl secrets make the power and killer rip in 4 cell........

And.....what rollout would ya all use for tracks 145-173 ft runline???

Kris
 

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u tune the motors the same.. the fact is 4 cell is alot slower then 6 cell... get your gearing right .. and setup 4 cell is 90% setup... the better the car works the faster it will be.. u can ionly go so fast on 4 cells. speed wise.. so efficiency is key..

aas fo r rollout.. every track is different.. how wide are the lanes, turns ect all that pays in.. try starting about 2.0 rolout.. go up an d down from there... stock seems to be right around 19t rollout,..
 

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The guys are right, 4 cell stock racing I have found is about 90% chassis, 5% motor, and 5% batts.

You could have a 77 watt Monster motor and it means nothing if the car is not setup properly and efficient. And not to be mean but when most guys think their setup is good, most of the time it can be better.

A good rule of thumb I use is:
I set a goal with my car. Say 50 laps is a top 3 run at a given track. Try and achieve those lap times with practice motors and sticks. If you can get the car really good then big mojo and sticks is just icing on the cake and will make you even faster and might even push you to a 51 lap run!!!!

But anyway, getting back to the question at hand.
As with just about any motors these days, whether it be stock, 19T or mod, once the motor is setup correctly (shimmed properly, hoods aligned, magnets are strong, good balanced arm, etc) Its all about the BRUSH....and the batch they came out of.

Just becuase Brand X worked this month does not mean it will stay consistent (sorry but this is just a fault of the brush process and quality control at the plant or lack there of, I should say....afterall R/C brushes are only a % of a very tiny % of all brushes made out there.)

My suggestion is try and buy a couple pair of each brush out there, 767, 769, Put Green, 4499, Hurriane Gold, etc and see which work well. Then try and buy as many from the good batch as possible.

Hope that helps
 

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I agree with erock, almost everyone at my track uses the 767's, a few use putmans, with a batch a while back that was super. But now there not as good. I had a guy a arm for me and he used the Fukuyama brushes and I like then better than anything I have tried before.
 

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try lightspeed brush 3910 purple spring on the positve side drill a cavity in the middle add comdrops and go fast... the negtive side a red spring 767 or 4499 ether will work.bend the spring back a little on this side.brake in your motor for 3 minutes 2 volts spray ouy motor and re com drop the positve brush leave negtive in the motor.This works for me. Seems to work on monsters and the new epics.hope this helps.
 
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I agree as well with erock, before you can make speed with motor/batteries find the setting that gets car around the track. Get with guys who are using athe same chassis find their setup and adjust from there. Speed a day or two trying different chassis setups until you find the one that gets you around the track faster. Now go for motor setup - that can take more than just brush and springs changes if you use an off the shelf brand - most of the aftermarket guys will a motor that's tuned for good power - only thing you need to do is find the right rollout for the track. I don't race much stock mostly 19turn ARCOR motors and some mod. Standard setup is usualy purple springs or red/purple with either Reedy 769 or 767 for standup brushes Putnam X brush. For off the shelf motors an assortment of motor shims to aid in aligning the armature, hood alignment tool and someone who can true the comm. For batteries a charger that can charge at least up to 6amps, (I use 6.50 to 7 for 19t and 5.50 to 6 for mod) and a string of 16bulb (32amp) for discharging.

Chassis setup changes (10L4) a bit on whether it's banked or oval. Harder springs on front(Wolffe black) for banked on flat its Green - battery position is generally down the center for banked, all the way out for flat. No tweak to just a little for banked to more tweak for flat-had to adjust a little more or less as track was run on. For banked Jaco blue (FR), White (rear), Black (front), White (rear) with traction compound application varing banked 1/4 to RF, none LF whole rear tires letting it soak longer on rear, Flat LF 1/4 inner, RF 1/4 to 1/2 or 3/4 and none on LF to whole rear tire with fronts soaking a little longer. Shocks: Center shock 40wt oil black spring (banked) , silver (flat) side shock 30wt oil red/blue (banked) gold/blue (flat). Camber 1.5 positive (LF) 2 -2.5 negative (RF) flat, 0 -1.5 negative (LF) 2-2.5 negative (RF) banked. Short wheelbase for flat, long wheelbase w/extended motor pod plated for banked.

As some mentioned things are constantly changing, what you find may be a great brush today could end up being a so so brush later. Right now the Reedy 767 or 769 hollow for laydown motors is the hot setup, the Putnam Green shunt tends to produce power between 2-4 runs and harder on the comm for standup brushes the Putnam Xbrush is now the hot setup. With motors producing higher rpm the hot setup is purple/red or both purple springs tweaking spring for more or less tension to reduce arcing and bouncing.
 

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Putnam Brushes...

Putnam brushes not as good as they used to? Putnam brushes good only for a few runs??? C'mon guys there's obviously something wrong with your motor program!

I'm currently running (2) ROAR Stock motors that have more than 15 runs on both of them and they're only getting stronger: I didn't even pull a spring out ... same brushes, same everything. If you gear your motor properly and clean it after each run, you shouldn't have any problem getting 20+ runs before rebuilding the motor (com trued, new brushes).

When rebuilding my motors I simply true the com, put in a new set of brushes (trailing edge cut down so the brush face is down to approx. 0.170"), break-in the motor @ 2.5V for 5 minutes (3 drops of bullit on each brush). I then run the rebuilt motor for a few "easy" practice runs on the track with a mild rollout and then test it on the dyno ... just to make sure everything is allright. Then I let my race results speak for themselves ... dyno do not win races.

Steve.
 

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Everytime I run a stock motor more than 2-3 times on the same brushes, the motor falls off about 3 min into the run and I lose a tenth compared to new brushes and a fresh cut. And my stockers do not get hot either. I usually come off at 80-95 degrees so I know I am not missing the gear. I have tried re-cutting and leaving the same brushes in with no luck either on the track.


20+ runs on a motor between builds....yikes
Wouldnt you have to make about 10 passes on the com when re-cutting.
 

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Be honest Steve, say at a race like the Snowbirds, would you honestly run a motor with 20 runs on it in the main without cutting and rebrushing it??
 

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I'm applying 7 drops of bullit on the back of each brush before each run and cleaning the motor after each run: I spin the motor using an electric dremel (counter clockwise) and flush it with motor spray.

Steve.
 

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If the motor is good on the track and the dyno doesn't show any problem (amp draw graph) it's not going to be rebuilt. My brother ran stock the last few years (snowbird nats) and that's what he did.

Steve.
 

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Racin Steve said:
Once you get in the top 10 at the Snowbird Nats, you don't get beat by better motor/batteries but better handling cars.

Steve.
I agree 100%

Next time I run stock I will give the motor a few more runs and see how they perform.
 

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As for gearing you have to find the proper one so you won't have to break on curves or just a little bit.

Also check your tires; from personal experience (or plain stupidity) tires below 34-35 are way too soft especially on track with new carpet. I start to think you don't need tires that soft because cars don't carry as much weight as on 6cell classes, around 1100 gr.(4cell) compared to around 1250 gr.(6cell).

Just as Steve says clean motors frequently, shoot some air in, anything to keep it as fresh as new.

Stephane Courchesne
 
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