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Old 10-17-2006, 02:56 PM   #316
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John: so I guess what you're saying is that for tecnical tracks, low-med traction, the best set up would probaly be with a saddle pack style batt set up; on larger, faster tracks, low mid traction, a center/inline set up would better?
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Old 10-17-2006, 03:00 PM   #317
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Quote:
Originally Posted by John Stranahan
I think the answer has more to do with the actual speed the car will reach. If the weight is toward the rear you will have more forward traction as the rear wheels have more load. Good for a short track. If the car is reaching 50 to 60 mph you will start to have instability with too much weight in the back. The car will tend to become airborne on the bumps if there are any on the straight. A more even weight loading might be desirable. I have recently added a little weight to the front of my wide car even though it has inline, but very light, battery pack.

Given the same weight front to back on two cars one that is wide and one that is narrow I would center the weight on the wide car to have it turn faster. Weight on the perimeter of the narrow car would slow its spin rate and make it more drivable on a loose track. On a high traction track I would keep the weight centered on both cars. This is based on driving both the narrow and the wide car and noting the differnece in high speed stability and spin rate on the two on both low and high traction surfaces.

I would still avoid saddle pack cars so that I could run LiPo's eventually with it. Lipo's do perform much better in the car in spite of my problems with them.
I'm going to agree and disagree....

at 50-60 MPH you are now relying on downforce to keep the front down. IMO keeping the static weight over the rear wheels to get you traction and then rely on downforce to keep you planted is a much better route with a pan car. Think about the cars we are modeling, most are Mid and Rear engine cars, the fronts are very light in comparison.
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Old 10-17-2006, 03:01 PM   #318
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John & rest of crew: concerning saddle packs: that's non-issue now, since MaxAmps makes nice LIPO saddle packs in 4400mah and 5500mah versions, or you can just get the awesome Thunderpower 8000mah packs, and cut off the black plastic "shell" that wraps the LiPO, and its a saddle pack! I ran them with my Xray T1R and they worked great...so, this could also be applied to Corally C10X or CCT or Associated L3T, which use/support saddle pack set ups, and them all one would do is move tem up or down on the chassis to find the balance sweetspot or tweak weight distribution for desired effects...
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Old 10-17-2006, 03:04 PM   #319
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Quote:
Originally Posted by vtl1180ny
I'm going to agree and disagree....

at 50-60 MPH you are now relying on downforce to keep the front down. IMO keeping the static weight over the rear wheels to get you traction and then rely on downforce to keep you planted is a much better route with a pan car. Think about the cars we are modeling, most are Mid and Rear engine cars, the fronts are very light in comparison.
I believe you have a point here...maybe John or someone else can explain their position?
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Old 10-17-2006, 03:09 PM   #320
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I've been thinking about getting 2 MaxAmps 5500's and attaching them to my L2 and L3t...
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Old 10-17-2006, 03:15 PM   #321
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Originally Posted by vtl1180ny
I've been thinking about getting 2 MaxAmps 5500's and attaching them to my L2 and L3t...
Me, too. I'll berunning the L3T with Lipo saddle pack, and then just move them up or down accordingly to get right traction effect as needed. It should work great...
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Old 10-17-2006, 03:18 PM   #322
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Quote:
Originally Posted by John Stranahan
yyhayyim- I don't like the fact that it only has one arm. No negative camber gain on roll. [color=red][b]tweaked t-bars vs sagged flexure...
They dont have to be aluminum arms. Softer, more flexible plastic/carbon composite arms, or even delrin arms, can get you the desired flex, while keeping the profile super low...
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Old 10-17-2006, 03:33 PM   #323
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Quote:
Originally Posted by yyhayyim
Me, too. I'll berunning the L3T with Lipo saddle pack, and then just move them up or down accordingly to get right traction effect as needed. It should work great...
I have a set of T1R battery straps I still need to fit only mt L3T...


I've pretty much always run my batteries all the way back....
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Old 10-17-2006, 03:52 PM   #324
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Here is the thing. Those full size cars have a real suspension in the front. Probaly have 3 - 4.5 inches of front travel.

I have exactly 2.5 mm of front travel. That's .1 inch. In real scale that would be 1 inch. That is just not enough. At speed the bump will lift the dam, all bets are off if there is not enough weight to pull it back down in the next few milliseconds. Forget lifting the throttle. It happens way too fast. I have some experience here on a long rough track. The pan car nats was discontinued from this very problem. I would rather the bump lift the wheels and scrape the dam. I stick by my statement. now if you are running 6 cells NiMH you have about 7 more ounces of weight on the car. Front end lift may not be such a problem. I have never liked saddle packs just from the Kiss principle that Pro-ten Holland brought up. Now tell me how a sideways six cell pack is different, other than appearance, than two 3 cell packs in a saddle pack placed toward the back. Certainly that angled center shock is not much improvement over a high shock except for a tiny bit smaller center of gravity. My car actually handled much better outdoors when I raised the center of gravity with the body.

YYhayhim-Tell me on the Corrally C10 X. Is the camber and caster Adjustable. Can you get front springs?

Roll Centers
I have done some thinking (and sketching) on roll centers at the front of the Associated car. I have a feeling that it does not change at all when you tinker with the angle of the upper arm, it always ends up centered at the level of the lower arms which are parallel to the ground. I welcome discussion on this. You do affect camber changes by tinkering with the upper arm. With two moving A-arms you would have the ability to actually lower the roll center for Asphalt. The front roll center is really high on my car, thats why a high center of gravity caused such an improvement.

I have though about the rear roll center on these cars as well. I don't think you can call the rear pivot the roll center and my test with lowering the pivot certainly reflect this. On a full size car with a solid rear axle, leaf or coil springs, no Panhard bar or Watts link, the rear roll center is centered on the axle. The panhard bar or Watts link is added to make this adjustable. I think that on our pan cars the rear roll center is at the ground and moves quickly to the outboard corner of the outside tire on roll since everything is solid back there.

Last edited by John Stranahan; 10-17-2006 at 04:15 PM.
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Old 10-17-2006, 04:01 PM   #325
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I know all about cars playing airplane at high speeds, had one get no less than 6' of air and then tumble a good 30+ times... And that was a Nitro which weighs much more than an EP Pan car....
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Old 10-17-2006, 04:06 PM   #326
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Well then!!! Do you see my point.

Was it caused by suspension bottoming. How did you fix the problem.

Last edited by John Stranahan; 10-17-2006 at 05:09 PM.
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Old 10-17-2006, 04:13 PM   #327
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Quote:
Originally Posted by John Stranahan
Here is the thing. Those full size cars have a real suspension in the front. Probaly have 3 - 4.5 inches of front travel.

"I have exactly 2.5 mm of front travel. That's .1 inch. In real scale that would be 1 inch. That is just not enough. At speed the bump will lift the dam, all bets are off if there is not enough weight to pull it back down in the next few milliseconds"...

you're right...I've also expereinced similar results. With 12 scale cars, I have run both CRC carpet knife and T-fource. Carpet knife uses 4 cell sidexside sideways, and T-Fource uses the 4 cell sidexside saddle pack, unlike the Associated L4 4 cell saddle pack. The T-Fource had better traction and stability than the Carpet Knife every time. The problem is that unlike the Assocaited car, you cannot move batteries up or down. Now, Bruce, from SpeedMerchant explains that the pblm with T-plate cars is that when it encounters a bump, its the t-plate which receives the first impact and absorbs the "hit", and then the shock and side springs react, making it less stable, smooth in bumpy surfaces like asphalt, which is why he has designed his SpeedMerchant Rev 4 cars witht he pod-link style system, which allows shocks and dampening to absorb bumps first and thus make it truly work and makes cars much more stable easier to handle. Also, he belives that side springs and dampeners need to be as far out as possible, unlike some car designs out there which have them more towards the center.

"Also tell me on the Corrally C10 X. Is the camber and caster Adjustable. Can you get front springs?
For Corally C10X and CCT, yes, the camber and caster are adjustable, as per corally website specs and kit info. You have to look at one and see what I'm talking about. Much more suspension travel on the C10X and CCT than Associated type suspension, and its lower profile. I love it, and its much smoother on the track. When you take the Corally CCT suspension and put in on Pantoura or Assoc L3T, you will notice a great difference in handling over bumpy rough track situations; its smoother and seems to just glide over like a TC! Concerning springs, have not looked into if they have more springs options, but I'm sure they do. Also, take a look at the rear suspension on Corally CCT and C10X...no rear shocks! its different and saves weight. Cars are truly top quality. I'm impressed and very happy. Someone should pick up on their design and see how they can be improved on or just buy and run them. Stormer has them in now in stock...
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Old 10-17-2006, 04:14 PM   #328
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John: you're right...I've also expereinced similar results. With 12 scale cars, I have run both CRC carpet knife and T-fource. Carpet knife uses 4 cell sidexside sideways, and T-Fource uses the 4 cell sidexside saddle pack, unlike the Associated L4 4 cell saddle pack. The T-Fource had better traction and stability than the Carpet Knife every time. The problem is that unlike the Assocaited car, you cannot move batteries up or down. Now, Bruce, from SpeedMerchant explains that the pblm with T-plate cars is that when it encounters a bump, its the t-plate which receives the first impact and absorbs the "hit", and then the shock and side springs react, making it less stable, smooth in bumpy surfaces like asphalt, which is why he has designed his SpeedMerchant Rev 4 cars witht he pod-link style system, which allows shocks and dampening to absorb bumps first and thus make it truly work and makes cars much more stable easier to handle. Also, he belives that side springs and dampeners need to be as far out as possible, unlike some car designs out there which have them more towards the center
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Old 10-17-2006, 04:31 PM   #329
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It looks like Corally does make more springs for diff tuning options for CCT and C10X...see following link: http://www.corallyusa.com/istar.asp?a=29. Its from the Specialized RC website(Corally).
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Old 10-17-2006, 06:14 PM   #330
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Quote:
Originally Posted by vtl1180ny
I saw that front suspension a while ago, I think it's more intended for the dirt oval guys than the carpet track....

Marty, couldn't the F1 front suspension be modified to fit a pan chassis?
Well I think the setup is more inline with the F103GT and should be good for a D Drive Touring car like the F103GT.

I am out to make a GTP Chassis (you know this all to well) following most or all of what I do.

See the F206F1 its strut rod is set at 38 degs and in a Pan car it would be around 28 degs and might be to low but I will make that one first for I have everything here to do it.

What I have found I got a few bodies here and an old 1/10 scale pan car I did run at one time years ago I think the (X) system and F1 setup would be the 2 I try first.
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