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Old 12-27-2004, 04:35 PM   #1
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Default 4 Cell Sedan Racing

This has be brought up and discussed on several threads recently so I though it should have its own thread.

We are at a point where our batteries can supply enough current to power an arc welder. Quite a few mod drivers can attest to that as some of you have DNFíd races due to shorted motors and found copper bridges across you comm slots! In conversations with Mike Reedy and Oscar Jansen both have said it would be a good idea to lower the cell count on our sedans. Lowering the cell count is a good idea for several reasons:

1. Less voltage = less peak and spike amp draw which leads to cooler longer lasting motors.
2. Less amp draw means less stress on batts and longer pack life.
3. Less amp draw means longer run times. Making time is less of an issue in mod and Stock and 19T motor racers will spend more time in the fat part of the voltage curve.
4. The cars are easier to control for racers of all levels. Tops speeds are virtually the same but less punch makes for an easier car to drive.
5. 4 cell packs cost 2/3 of what a 6 cell packs costs.
6. Rubber and foam tires would last longer.
7. Lighter cars handle better.

Reedy had a few AE drivers test with 4 cell packs and found that lap times are only off by ~2/10ths on most tracks. Top speeds are pretty much the same. The only difference you can feel is a little less punch coming out of corners.

I propose the following initial guidelines for 4 cell sedan racing:

- 27T Stock 4cell should be the novice class. It is fairly slow and allows driver to learn without breaking their cars all the time.
- 19T 4 cell should be the stock class.
- Mod 4 cell should be open motor.
- Min Weight should be 48.5oz on rubber tires and 45.5oz on foam tires. (normal weights minus the weight of 2 cells).
- Racing should remain at 5 min. We donít want to do one thing to take run time out of the equation only to extend race times and make it an issue again.

I encourage you guys to try it. Donít knock it until you try it. Quite a few other have and have had very positive experiences with it. 4 cell racing is the main reason for the resurrection of Oval racing a few years ago. The top racers in all classes are going just as fast now as they did with 6 cell cars a few years ago. However, they are enjoying better motor life, battery life and lower costs.
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Old 12-27-2004, 04:38 PM   #2
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Sounds interesting. People like me (on a slim budget, and no driving skills) should like it as well as seasoned veterans should like it.
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Old 12-27-2004, 04:46 PM   #3
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I like the idea. But how would we incorporate this into say something like Roar, or IFMAR? I know some people and some tracks don't care for Roar (for example). But it helps if someone like "them" stepped up to the plate and adopted this format. I think it would help other tracks follow this "example" instead of saying... "Well I'm not gonna do it because Roar doesn't." Or just say screw Roar and let them deal with offroad. We'll adopt a whole new structure for Touring Cars and 12th scale?

I'd love to do it, it's just getting other people to do it as well. I'm gonna try it out this weekend with 19t. I'll just toss in one of my 12th scale packs and go at it..... You did say gear up a couple teeth right??
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Old 12-27-2004, 04:52 PM   #4
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Default Re: 4 Cell Sedan Racing

Quote:
Originally posted by AdrianM
This has be brought up and discussed on several threads recently so I though it should have its own thread.

We are at a point where our batteries can supply enough current to power an arc welder. Quite a few mod drivers can attest to that as some of you have DNFíd races due to shorted motors and found copper bridges across you comm slots! In conversations with Mike Reedy and Oscar Jansen both have said it would be a good idea to lower the cell count on our sedans. Lowering the cell count is a good idea for several reasons:

1. Less voltage = less peak and spike amp draw which leads to cooler longer lasting motors.
2. Less amp draw means less stress on batts and longer pack life.
3. Less amp draw means longer run times. Making time is less of an issue in mod and Stock and 19T motor racers will spend more time in the fat part of the voltage curve.
4. The cars are easier to control for racers of all levels. Tops speeds are virtually the same but less punch makes for an easier car to drive.
5. 4 cell packs cost 2/3 of what a 6 cell packs costs.
6. Rubber and foam tires would last longer.
7. Lighter cars handle better.

Reedy had a few AE drivers test with 4 cell packs and found that lap times are only off by ~2/10ths on most tracks. Top speeds are pretty much the same. The only difference you can feel is a little less punch coming out of corners.

I propose the following initial guidelines for 4 cell sedan racing:

- 27T Stock 4cell should be the novice class. It is fairly slow and allows driver to learn without breaking their cars all the time.
- 19T 4 cell should be the stock class.
- Mod 4 cell should be open motor.
- Min Weight should be 48.5oz on rubber tires and 45.5oz on foam tires. (normal weights minus the weight of 2 cells).
- Racing should remain at 5 min. We donít want to do one thing to take run time out of the equation only to extend race times and make it an issue again.

I encourage you guys to try it. Donít knock it until you try it. Quite a few other have and have had very positive experiences with it. 4 cell racing is the main reason for the resurrection of Oval racing a few years ago. The top racers in all classes are going just as fast now as they did with 6 cell cars a few years ago. However, they are enjoying better motor life, battery life and lower costs.

Top Speed cannot be the same. It's a voltage equation and lower voltage means less RPM and punch. Eventually, we'd drop down to 3 turns to get the speed back where we want it.
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Old 12-27-2004, 04:53 PM   #5
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Adrian- we should bring this up at Joe's race and see if anyone in Florida would be interested i would love to see races made longer(especially stock) my batteries are o.k. and still come back with over 100 seconds at 30 amps.
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Old 12-27-2004, 04:54 PM   #6
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There will be quite a bit less weight, I agree the top speed will more than likely be a little slower, which is why he proposed 19t as the "stock" class. I think it sounds good.
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Old 12-27-2004, 05:01 PM   #7
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I know a few guys that have been running this at their local club. From memory i think they were running 10 turn motors. Fairly sure they agreed that the cars were good to drive, and they said that power was somewhere in the region between 27 and 19 turn 6 cell.
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Old 12-27-2004, 06:46 PM   #8
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The top speeds in oval are pretty much back up to where they were in the 6 cell days. Motors, cars and gearing have been optimized for 4 cell for Oval racing.

Derek - You are correct...we would drop a turn or to to boost the amp draw/wattage output and get more speed/rip. At club races I usually run 7 or 8 turn mods. On 4 cell we would run 6 ot 7's. Keep in mind that brushless is also on the horizon. Brushless motors can be made quite a bit more wild than current mods. Its pretty hard to get a sub 6 turn brushed motor to run properly. It is just too inefficient. It draws a lot of amps and and dosen't run much better than a 6. Brushless motors can be made considerably wilder than a 6 turn.

With regards to ROAR and IFMAR. Racers have to try new things. If they gain broad acceptance then the santioning bodies create rules and bring the new classes into the fold.

Roly - Stock 4 cell sedan is rather....sedate...lol! Great for novices but not enough fun for experienced racers. Try 4 cell 19T at Coral Springs. Start 3 teeth higher than normal and keep adding a tooth every run until you so no more lap time improvements.

MattW - Tell the guys to try a bigger ratio. In 1/12th we went up 8 teeth on the pinion when we went from 6 to 4 cell (25/100 to 33/100). A 10T mod on 4 cells should be faster than 6 cell 19T when geared properly.

I can't take credit for this idea. Mike Reedy has been talking about this for at least 3 years. He's been wanting to do it at the Reedy race at Tamiya for the last 2 years but didn't want to tie up entries/time with an exibition class.

Thank you all for your positivity. Like I said, give it a shot you will be pleasantly surprised.
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Old 12-27-2004, 07:19 PM   #9
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This is an idea that I have been tossing around for my son in novice class for a while. I think it is a great idea.

ROAR and the other sanctioning bodies did not start the 4-cell oval craze, that was started by the racers and then the rules were changed. So, I think we need to work on this at the local level and prove it. Once it is proven, it will gradually be accepted. With oval, it took a while for everybody to accept the changes, but it did happen.
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Old 12-27-2004, 07:24 PM   #10
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This is one of the better ideas I have heard lately. I remember when we went to 6 cell in offroad. It was by choice. The cars ran better with a lower wind and one less cell. Cars were making to much bottom end power and you would just spin the tires. First we switched in 2wheel, then truck, and 4 wheel was split about half the guys still running 7 cells when the rule change came down.

Last week I was spinning the tires coming out of the croners on carpet. I wouldn't mind switching to 4 cell and might even run some parking lot races against some 6 cell cars this summer. We have a pretty low bite sealed asphalt track that 4 cell might be the way to go.

Thanks for bringing it up Adrian.
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Old 12-27-2004, 07:35 PM   #11
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This is a very interesting idea! It's nice to see people are thinking outside the box and considering different avenues based on the history of other successful classes.

I'd gladly try this at my local track if just a few other locals would go along with it. Our track has the policy of "3 cars makes a class" for any of the non-traditional cars (or trucks). On a related note, some of the more serious racers at my local track are going to start running 1/12 touring cars, which only use 4 cells. This is an effort to have a fun class that doesn't break the bank. These cars run 1/10 tires, and in the winter months of foam tire usage, they get the leftover "skins" from the 1/10 cars. This makes it super cheap to run them!

With the impending onslaught of super capacity cells, this may become a necessity as opposed to a novelty!
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Old 12-27-2004, 08:07 PM   #12
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We take a step forward in motor development, now you want to take two steps back in batteries, if you can't handle the power start a mabuchi class!!!
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Old 12-27-2004, 08:19 PM   #13
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just my 2 cents: i think 4 cell sedan should be a seperate class---if it is even done at all, but the rest of us that are into racing for speed and power should still be able to run 6 cell(maybe im not understanding all this) just my 2 cents
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Old 12-27-2004, 08:24 PM   #14
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every major (real cars) type of racing takes some steps back every couple years or so to keep the cars under control or the class dies, F1 has been continuosly trying to slow the cars down. Whatever happened to 1/10 pan car racing? way too fast for the motors and batteries that were available and it died, luckily TC's came out soon after and onroad racing survived. I for one was getting tired of replacing brushes every run just to be competitive in mod and maybe the 4 cell class is where we have to start to keep TC racing going strong. I'm not sure how the top pro's will feel about this but they aren't the majority of racers, they just get their positions heard more because of who they are. If Mike Reedy suggested this and Oscar Jansen brought it back up then maybe there is something to it? It seems to have two of the three motor manufacturers behind it already, and they would be the ones to know that we are overtaxing our motors as it is now and we need a change.
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Old 12-27-2004, 08:36 PM   #15
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What about car design? Most cars that run a side by side arrangement might be unbalanced by this arrangement. Of course a car like an Xray wouldnt care one bit.

I wonder if you could find a baseline that that alows guys to run either. For example-guys running 4-cell get a weight break. if ts gets to the point where people are running clear bodies and no plastic on there electronics to get cars as light as possible-well that stupid-then add weight to the 6-cell cars till they run pretty evenly.

I think this has some merit.

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