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Old 10-29-2013, 12:32 PM   #3316
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Originally Posted by howardcano View Post
That's not what I meant. It's okay if the entire rear pod can pivot, like on a T-plate car, as long as the engine, transmission, and wheels move together as a unit. What we don't want is for the rear wheels to rock side to side while the engine and transmission remain fixed (similar to a DeDion rear suspension). This can be done with any arrangement that has half-shafts on the rear end, or even with a solid axle using a belt drive to its center.

I believe that's what this rough translation of the French rules forbid:

"If rear axle articulated levels of driving the dynamic axis of the drive wheels must be attached to a same element."

EDIT: Any rules suggestions I make will always allow existing cars (that I'm aware of) to compete. I kinow about your T-plate car. What I want to avoid is someone designing a car that abides by whatever the rules are, but is sufficiently different and quicker than existing cars to make them obsolete
(regardless of it being true or simply the racer's perception).
I get it...... So now we have a fairly solid rule set.... Now how do we get electric
guys to the nitro races???...... And how to change their minds that nitro
racing can be affordable???.....
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Old 10-29-2013, 01:13 PM   #3317
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Let me offer the practical suggestion that we create exactly one post for the rules, so everything is in one place, and everyone can refer to it. What is decided here can serve as a common bond for everyone in the US. We can keep that one post updated as we go.

This is essentially how VTA, USGT, UF1, and other popular electric classes were started!

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Originally Posted by aarcobra View Post
post #3294:

1) Any 2wd chassis that has no obvious form of independent suspension Rear wheel drive only (Locked Suspension cars allowed but not recommended)

2) No variable or multi speed transmissions

3) 5 or less port engines (More ports allowed but not recommended)

4) Any approved body

5) Minimum weight 2300 grams (with transponder, no fuel)

6) All other applicable ROAR rules apply

Let me know of any additions or changes I'll get something done!!
Lets get something settled on this and move on to other things!!

Ned
Ned, would you like to maintain your post #3294 for this purpose?
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Old 10-29-2013, 02:36 PM   #3318
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Originally Posted by howardcano View Post
Let me offer the practical suggestion that we create exactly one post for the rules, so everything is in one place, and everyone can refer to it. What is decided here can serve as a common bond for everyone in the US. We can keep that one post updated as we go.

This is essentially how VTA, USGT, UF1, and other popular electric classes were started!



Ned, would you like to maintain your post #3294 for this purpose?
I would vote yes Gary Andersen also I purpose have pan classs nationals in 2014
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Old 10-29-2013, 04:15 PM   #3319
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Quote:
Originally Posted by howardcano View Post
That's not what I meant. It's okay if the entire rear pod can pivot, like on a T-plate car, as long as the engine, transmission, and wheels move together as a unit. What we don't want is for the rear wheels to rock side to side while the engine and transmission remain fixed (similar to a DeDion rear suspension). This can be done with any arrangement that has half-shafts on the rear end, or even with a solid axle using a belt drive to its center.

I believe that's what this rough translation of the French rules forbid:

"If rear axle articulated levels of driving the dynamic axis of the drive wheels must be attached to a same element."

EDIT: Any rules suggestions I make will always allow existing cars (that I'm aware of) to compete. I kinow about your T-plate car. What I want to avoid is someone designing a car that exploits something not addressed in the rules, and is sufficiently different and quicker than existing cars to make them obsolete (regardless of it being true or simply the racer's perception).
We're working on a t-plate build as well, and the rear pod (tires, axles and diff) are independent of the transmission and engine. We're forced in that direction simply because of our Kyosho style drive...everyone else has their entire unit in the rear, and our engine is a mid-mount. You'll have to count Tom and I opposed to that rule proposal. Also doesn't seem fair in light of the WRC's where the entire front can rock, I don't see a difference between one or the other.
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Old 10-29-2013, 04:21 PM   #3320
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Originally Posted by hitcharide1 View Post
We're working on a t-plate build as well, and the rear pod (tires, axles and diff) are independent of the transmission and engine. We're forced in that direction simply because of our Kyosho style drive...everyone else has their entire unit in the rear, and our engine is a mid-mount. You'll have to count Tom and I opposed to that rule proposal. Also doesn't seem fair in light of the WRC's where the entire front can rock, I don't see a difference between one or the other.
Thanks for the update. I thought that your design was with everything locked together, but maybe that was a previous iteration.

If we will allow this, then I'll invest some time in a re-design of what I have so far. Or, alternatively, I may become a customer of yours!

Are you far enough along to share photos?
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Last edited by howardcano; 10-29-2013 at 05:01 PM.
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Old 10-29-2013, 05:00 PM   #3321
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How about liquid-filled dampers (shocks)? I'd prefer to not allow them. What does everyone else think? Are there any cars currently racing that use them?
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Old 10-29-2013, 07:08 PM   #3322
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How about liquid-filled dampers (shocks)? I'd prefer to not allow them. What does everyone else think? Are there any cars currently racing that use them?
.... No one has used them.... Not that I saw...
BAN them completely...
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Old 10-29-2013, 07:50 PM   #3323
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Default Suggested Pan Class Rules 10-30-13

This will be the "official" listing of the suggested pan car rules some of us are trying to come up with get things "off-center.
I will update it as the consensus seems to suggest and it can be adopted, by whoever sees fit!



1) Any 2wd chassis that has no obvious form of independent suspension Rear wheel drive only (Locked Suspension cars allowed but not recommended)

2) No variable or multi speed transmissions

3) 5 or less port engines (More ports allowed but not recommended)

4) Any approved body

5) Minimum weight 2300 grams (with transponder, no fuel)

6) All other applicable ROAR rules apply

7) No liquid-filled dampers (shock absorbers) allowed. (added 10-29-13)



Let me know of any additions or changes I'll get something done!!
Lets get something settled on this and move on to other things!!
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Old 10-29-2013, 07:54 PM   #3324
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Originally Posted by howardcano View Post


Ned, would you like to maintain your post #3294 for this purpose?
Howard, Gary,

I will be glad to maintain a post for keeping track of rule suggestions. I have cleaned it up and added "no liquid...dampers". It is Post #3323.

Ned
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Old 10-29-2013, 08:05 PM   #3325
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Default FYI

[QUOTE=hitcharide1;12675157]

I suspect the reason WRC went with a wobble front end is that there is no other way, without suspension, to keep all four tires on the ground in a turn.
Rigid aluminum chassis aren't very flexible.

The chassis on all the Modern Classic pan cars I have seen are not rigid they are very similar to the flexibility of the vintage pan cars. My DFX has a g-10 fiberglass pan and Lon has run one at times as has Rick.



QUOTE]
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Old 10-29-2013, 08:32 PM   #3326
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These are all excellent observations of what a pan car should be!

Thanks! I'm trying to make sense of why the front end is such a big deal to some people.

This is done so the corner weights ("tweak" in RC-speak) don't change as the tires wear unevenly. As I have posted before, it is not optimal for handling. Putting all of the roll stiffness at the rear of the car makes the rear end loose
and reduces traction out of the corners.

If tire wear induced tweak is the only reason for the articulated front end it is not a big deal since 40 to 50 duro front tires very little wear on prepared tracks!

It would be much better to make the front end stiff in roll, and put the rear tires on a pivoting arrangement.

Actually from my admittedly limited experience and observations of these cars, I do not believe the front roll stiffness is as low as you suspect. For instance I know that at least some of the set-ups pretty much "lock out" the articulation so that when you lift a front wheel, the flex/movement comes from the chassis plate not at the articulated joint. I have installed "tweak" screws in my plate, and it is only used to adjust "static" tweak the way the old MRP tweak plate did in the vintage days. I did see one car that the front end "flopped" from side to side, he was not at all competitive. Some of the cars have a little compliance but the "floppy flyer" did not look too hot!!

This is pretty easily done on a belt-drive car. (Again, I have posted this previously.) I would suggest that this NOT be allowed.

I think the European rule makers and manufacturers have/are struggling with this. The "Contact 300" car was revised because the rear end design was "pushing the limits". But, correct me if I'm misunderstanding, a "T-Plate" or other design that mounts the rear axle, engine, and drive train solidly on a "single" chassis part, would be ok....Key word-tires?
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Old 10-29-2013, 08:49 PM   #3327
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To me the defining characteristic of the nitro onroad pan cars (as opposed to their 1/10th and 1/12th electric cousins) is that there is no independent movement of the front wheels relative to each other, and the same thing in the rear. When I look at my WRC - and this is the only car I've stared at hard - the only "suspension" is the ability of the rigid front end to roll side to side in a controlled fashion relative to the rigid rear end. The WRC front rocker has no vertical movement at all - it is mechanically not possible based on the design. Any fore and aft flex in the car comes strictly from the flexiness (is that a word???) of the main chassis plate and the stiffness provided by the radio upper plate mounted on standoffs. That flex is controlled by the design and thickness and material of the plate (in the case of the WRC the company makes aluminum, fiberglass and carbon fiber chassis plates, and carbon fiber and aluminum radio plates). They also make a stiffner plate that you can screw onto the main chassis behind the rocker to control the fore and aft flex - it is not controlled in any meaningful way by the front rocker.

I think you could duplicate the movement of the front rocker if it was locked to the chassis by adjusting the width and material of the chassis between the front and rear ends of the car. However, to get enough flex, the car would be extremely fragile and easy to tweak, and any adjustments to the roll stiffness would have to be made by either changing the chassis or by adding or subtracting stiffening plates. The rocker design is just an easy to manufacture and easy to maintain way of giving the car enough flex to be driveable, while still staying true to the intent of the class to have no independent suspension of any wheel.

I agree that making the rear roll rather than the front would make the rear easier to hook up -- and that would be a bad thing. The beauty of the class to me is that by being rear traction limited horsepower becomes a non issue - any old crap pushes the car faster than it can be driven. It seems to me with my limited experience the class is about getting the balance right front to rear, and getting the rear to have the right balance between grip and slide so the car doesn't hop, diff out or slide excessively. It is definitely a car you have to drive, rather than point and shoot, and I like that.
I am pretty much in agreement with your thoughts and comments. I believe there are cars available that stretch the flexibility thing, and they have been available for a number of years. The WRC EVO MAY fall into this category. While I have not seen it to be an advantage, it may be in the future. I'm not sure why, but I have faith in the Europeans with experience in this class to police it keep the manufacturers in line.....

The Cinci Snow Ball race was a great example of the equality of the cars represented. Motonica P8C, P8C Extreme, WRC, DFX Vortex, DFX Premium, and a converted suspension car all seem relatively competitive.

Ned
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Old 10-29-2013, 08:53 PM   #3328
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I would vote yes Gary Andersen also I purpose have pan classs nationals in 2014
I could go for a Pan Car Nationals! Preferably in Toledo, or along I-75 (Dayton or Cinci).

Definitely not where a regional costs $50 to enter!
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Old 10-29-2013, 09:01 PM   #3329
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[QUOTE=aarcobra;12678105]
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Originally Posted by hitcharide1 View Post

I suspect the reason WRC went with a wobble front end is that there is no other way, without suspension, to keep all four tires on the ground in a turn.
Rigid aluminum chassis aren't very flexible.

The chassis on all the Modern Classic pan cars I have seen are not rigid they are very similar to the flexibility of the vintage pan cars. My DFX has a g-10 fiberglass pan and Lon has run one at times as has Rick.



QUOTE]
I agree. On the WRC, at least, the amount of flex between the 3mm glass chassis and a 2mm aluminum chassis seems very close to each other.
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Old 10-29-2013, 09:25 PM   #3330
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Originally Posted by howardcano View Post
Thanks for the update. I thought that your design was with everything locked together, but maybe that was a previous iteration.

If we will allow this, then I'll invest some time in a re-design of what I have so far. Or, alternatively, I may become a customer of yours!

Are you far enough along to share photos?
Our previous/current build isn't bad...it's the most durable thing on the planet and handles very well, but we still haven't gotten the flex we need to make it fully competitive. With the nature of our build, we only have so many options.

We've looked at modifying the front, a/la WRC but with a better design (or at least we think so) in mind. But that's just an idea on paper thus far, we're not fabricating a mock up yet.

A few months ago, when we were isolating gear issues, I was re-looking at my old Delta Super Phaser....the rear pod setup. When that car came out, it was incredibly fast, and pretty soon nearly every other manufacturer was making a quasi duplicate of it. By virtue of our shaft drive setup, we think we can do something similar, and it would allow us to NOT mess with the front, which we really like, since it's just about bulletproof....and I really hate to mess with something that already works. If the consensus is to outlaw such a thing, then we'll move another direction, but the preference is to modify the rear vs. the front. Within a month we should have a better idea, or at least a mockup, and I'll post pics.

We're sure we could change some things...and some things probably need changed. Our intent is to go to market with a product and offer a U.S. built alternative, but it must be fully competitive, or else, what's the point? But, some parts that we really like and are really bulletproof, we're loathe to mess with. F'r instance....

1. Most of the rear. Very solid rear bulkheads that allow for full rear camber/tow adjustment via the pillow balls, and allows for a Delta SuperJ style rear bumper.

2. Transmission. The Kyosho drive line works well, and thanx to Tom, the gear issues appear solved. It's really simple, it's cheap, and since it's centered on the chassis, it's well protected.

3. Front. Very solid bulkheads, a main shaft support between the two that also adjusts for very quick caster adjustment.

Yet, we've not gotten all the flex we want out of the chassis. We can probably improve on this by extending the bulkheads just a little further, and narrowing the chassis a little more...and that's the part I really don't want to do, because narrowing the chassis to allow more side to side flex also causes up/down flex unless some other fore/aft pivot brace is used. Some guys can get a pic in their head and reasonably determine how a change will work and be incorporated. I'm not one of those people...I have to actually build it in order to fully recognize it, so....give me a month and I'll report back.
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