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Old 12-30-2004, 01:29 PM   #256
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Great discussion and a perfect opportunity to discuss the future of our hobby as we enter the New Year. Thanks to Adrian for bringing this topic to the forum and encouraging debate.

Analogies to full scale racing are predictable, but are not entirely relevant. The focus on lowering cell count, as I understand it, is not an attempt to slow the cars down for safety, decrease the cost of racing, or even up the classes. Debates on these side effects of a change to 4 cells are understandable but somewhat distracting.

Most changes that have been made to the classes seem to be driven by the ever increasing capacity and performance of our batteries. Industrial needs for small, high powered, high capacity energy sources are universal and the technology for rechargeable batteries will continue to advance.

The point that Adrian is making is that motor design within the current framework has effectively reached its zenith. New advancements in motor design seems to be centered on increasing efficiency and durability of the motors under the extreme conditions of modified 6 cell racing.

The migration to 4 cell racing is therefore logical and will be easy to accomplish logistically. Most of the reasons have already been stated. Chargers and electronics equipment can already accommodate 4 cells and adjustments can be made to cars that were designed for 6 cells to compensate for the lighter weight.

From a racers point of view, I am skeptical about 4 cell racing in all classes. I acknowledge the problem with modified racing and the need to do something but I have difficulty accepting the need to adopt 4 cell racing across all classes. The problems associated with motor life and high amp draw with low turn motors are obviously not a issue in stock and 19T touring car.

One of the "benefits" of 4 cell racing that Adrian mentioned was that the cars would be easier to drive. While this is true and would immediately benefit the rookie drivers in their learning curve to drive fast, I disagree with with the need to implement it in current spec class competition.

We all know that slower is faster and laptimes will prove that the smoother, more consistent car around the track will do better against the clock. But what about the fun factor? What about the punch we get out of a tight corner or the extra little bit of UMPH when you pull the trigger to get around traffic?

It is my opinion that for competition, these cars should be difficult to drive, and should be overpowered. This is not a problem for the mod class but i'm afraid that losing 2 cells of available power in stock and 19T is just too drastic of a change. The top drivers will always adapt and remain on top, but I think the emphasis should remain on promoting drivers who have the skills to manage that extra horsepower. This should be the objective rather then a car that can be driven around the track at almost constant full throttle.

I believe the reason why 4 cell was so easily accepted into oval and 1/12 scale has more to do to with chassis design. The power to weight ratio in pan cars is enough that they remain overpowered and oval racers aren't concerned with the extra voltage needed to power out of a tight 180. This also should alert people to the possibility of resurrecting 1/10 pan cars and creating a new class: Pro10 w/ 4 cells and touring bodies.

If the decision is made to mandate 4 cell racing, then 27T Stock will definately be too slow for competition but the rules governing 19T will have to be re-evaluated as well. (15 turn? 13?) I know that you foresee this class becoming the "new stock class" but it will eliminate it as the intermediate alternative to modified that it is now.

I have no doubt that 4 cell racing in the modified class would be a good thing and I look forward to trying it myself. Lower turn motors and gearing will bring the speeds and lap times easily within the range of 6 cell cars, but I don't think the change should be mandated at the expense of the very popular stock and 19T spec competition classes that exist today.
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Old 12-30-2004, 02:10 PM   #257
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Great post Robert...

Racing would be less expensive on 4 cells. Batts would be cheaper, tires would last longer, motors too.

The issue with classes will get really complicated when brushless start to take off next year. The LRP/Reedy alternative to Novak will really get the class going as there are some guys that aren't Novak fans.
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Old 12-30-2004, 02:31 PM   #258
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If you guys really think 4cells are going to turn laps as close as 6cells do today, then the mod class should be open from 4 to 6 cells and it should be up to the racer who decides according to his taste and budget.

just my $.02

Omar R.
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Old 12-30-2004, 02:31 PM   #259
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Quote:
Originally posted by RobertV
...I don't think the change should be mandated at the expense of the very popular stock and 19T spec competition classes that exist today.
Great points. I would add, after trying the 4 cell mod TC 'experiment' during practice last night, that I think if given a chance the Stock and spec 19 racers would actually enojy 4 cell Mod more.

I found the car easier to drive than 6 cell stock, yet a lap or 2 faster across a 5 minute run.

This however was on a relatively small carpet track, which brings up the biggest issue I forsee.
4 cell Mod on a large flowing track will actually be closer to 6 cell Mod, whereas on the short technical tracks its closer to 6 cell stock. I feel this is so because of the decreased 'punch' of 4 cells though those 4 cells when geared appropriately will provide ample top speeds.

I think this discrepancy throws a kink into the 4 cell idea. I also feel that without major motor changes 4 cell stock and 19T wouldn't appeal to many if any.

Perhaps the swing in discussion on this thread to LiPo Brushless is the correct progression.
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Old 12-30-2004, 02:34 PM   #260
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I too had planned on running 4-cell 19t at practice tonight-but I may have to put it off till next week. Thanks for the first hand account JKA!!!

Ray
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Old 12-30-2004, 02:53 PM   #261
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If you go LiPo and Brushless, isn't it kinda deafeating the whole purpose of '4 cell' sedan? Technically, how many 'cells' are LiPo? I'm guessing there isn't 4 cell 4.8v LiPo cell pakcs. I've seen 4 cell 11V+ LiPo packs though. Even with brushless, this will open another whole can of worms. Let's be realistic, we're RACING. People will spend what ever needed to go faster then next guy. After couple years of running 4 cell, LiPo, brushless what ever, it'll be back to square one again. People who can afford to spend to go faster will keep spending $$, and people who can't, or won't will still be complaining.
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Old 12-30-2004, 03:20 PM   #262
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Kokam 2000mah LiPo cells are 3.7v each. They can safely supply 30A for short periods. We would be running what are called a 2S2P packs (~$110.00 Street price). 2 cells in a series and 2 cells in parallel. This works out to be a 7.4v 4000mah pack that is a bit lighter than a 6 cell pack. This pack is safe to use up to 60 amps of current. Anything higher for any period of time and BOOM!

Open Mod drivers would need a 2S3P (7.4v/6000mah, ~$160.00) pack that is safe up to 90 amps.
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Old 12-30-2004, 04:58 PM   #263
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Quote:
Open Mod drivers would need a 2S3P (7.4v/6000mah, ~$160.00) pack that is safe up to 90 amps.
Just run a 3s2p with a 4000 rpm/v brushless motor and things will work great. Plus, a 6-cell, 7 turn sedan wouldn't stand a chance against it.
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Old 12-30-2004, 05:48 PM   #264
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kufman's my hero....
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Old 12-30-2004, 07:02 PM   #265
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Quote:
Originally posted by AdrianM
Regarding Brushless...I don't know anyone that isn't excited by the possibility of running Brushless motors. The problem is that they are not mature technology yet in our application. Right now there is no drivable Brushless system that is as fast as a open mod brushed motor. Sure a you can get a Hacker and a huge speed control to go as fast but it is not as drivable and will not fit into a lot of current cars.

The limitation is speed controls...specifically FETs that can handle the loads and spikes and can still be purchased at a price that lets manufactures sell speedo's for less than $500.

Its coming. But we wont all be running Brushless for another couple of years or until all the bugs are worked out.
I run a 5800 novak system in open mod against 9 turn D6's and v2s with no problem. Actually i have won the A-main the last three times out with it. Correctly geared the Novak system is very competitive with brushed motors. Also i am using stick packs and a fusion club pack while others are using fusion's race packs and other expensive packs.. the new reedy motor is supposed to be a little bit more powerful and then brushed motors won't stand a chance I have had no heating or durability issues with it for the year i've owned it either

I race against people who have multiple mod motors, lathes, and all kinds of other stuff and the novak system has allowed me to compete against them. A brushless racing class would bring prices down especially at more competitive levels.
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Old 12-30-2004, 07:22 PM   #266
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If you want to have 4 cell touring car races then I think that Schumacher should sponser the races in the Florida state series for this year and see how it goes.
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Old 12-30-2004, 07:29 PM   #267
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Correct me if I'm wrong, but arent most 1/12 sedan chassis designed for 4 cell packs? Why not just open up that class & leave the 6 cell classes.
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Old 12-30-2004, 07:36 PM   #268
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Quote:
Originally posted by razzo
If you go LiPo and Brushless, isn't it kinda deafeating the whole purpose of '4 cell' sedan? Technically, how many 'cells' are LiPo? I'm guessing there isn't 4 cell 4.8v LiPo cell pakcs. I've seen 4 cell 11V+ LiPo packs though. Even with brushless, this will open another whole can of worms. Let's be realistic, we're RACING. People will spend what ever needed to go faster then next guy. After couple years of running 4 cell, LiPo, brushless what ever, it'll be back to square one again. People who can afford to spend to go faster will keep spending $$, and people who can't, or won't will still be complaining.
I agree with you Jeff and for that reason is why I think stock motors should just go away. People spend way too much trying to make them go fast. If you ran mod and you need more speed and can handle it all you have to do is buy a lower wind motor. If your a newbie you can start out with a higher wind motor and run in a novice or sportsman class. Face it, going fast doesn't have to cost you alot and most guys can't handle the really low wind motors anyways.
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Old 12-30-2004, 08:32 PM   #269
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Quote:
Originally posted by Peter Busch
I agree with you Jeff and for that reason is why I think stock motors should just go away. People spend way too much trying to make them go fast. If you ran mod and you need more speed and can handle it all you have to do is buy a lower wind motor. If your a newbie you can start out with a higher wind motor and run in a novice or sportsman class. Face it, going fast doesn't have to cost you alot and most guys can't handle the really low wind motors anyways.
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Old 12-30-2004, 08:49 PM   #270
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Wow,,,it's nice to see this debate is still going strong.

What bothers me here is that we only have on manufacturer rep. involved in this. I gotta give it to Adrian of Schumacher. Any body out there close to any of the other industry guys, get them involved. Let's get them on the spot. For the vast majority of us, we can only go on, What we've heard or read, or on rumor.

So lets call on Novak, Associated/LRP, Hitec, and anybody else that's involved in what we are talking about.

I have another question, Why do tires, be it TC Rubber, Off-Road Rubber or foams cost so much. A set of 4 mounted TC Rubber Tires $30+, Nitro Foams $15-20 for a set of 2, Stadium Truck Tires $18-20 a pair, Monster truck Racing (Revo, T-Maxx etc), $30-40 a pair, 1/8 scale Off-road $28-$40 per pair...

When I raced the ROAR Reg 12 race, I bought 2 sets of tires for the weekend, $67 with tax...I saw racers going thru the trash cans salvaging throw away tires. The factory guys cut the tires off the wheels then threw them away...

Tires are in issue in ANY form of motorsports, R/C cars, Karts, Nascar, F1, Open Wheel, Superbike, Motocross, Dirt Oval, Bicycle Road Racing, X-Country and Specially Downhill MTB racing, BMX...

So here's another issue toss in the fray.
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