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Old 02-18-2007, 06:21 PM   #946
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you running it on carpet?
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Old 02-18-2007, 06:29 PM   #947
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Yes.
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Old 02-18-2007, 09:15 PM   #948
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GreaseMonkey-I see. There are several pan cars in your fleet. I am building a narrow car as well for a medium size indoor carpet track.

Upper Control Arm Mount

I am still using the stock associated upper A-arm mounts, although I use two on each side. I had purchased spares, but they were not the same as the original mounts that came with the pantoura as there were no set screws to secure the hinge pins. Anyway the pic shows the mount that comes four to a tree for the RC10L3T on the left. It is available at a few web stores. This mount sucks. It is intended for use with the L shaped pin. Friction is supposed to hold it in place. The pin would not go through the arms, so I used the original straight pin. It did not develop enough friction to stay in place and caused a slow qualifier as it backed out. This mount is also too soft. I would get the graphite mounts on the right to avoid this problem. They are available at RC4less now as well as from Associated in a set of six. Part #ASC 4561 These fit the RC12L4 and the older cars as well. I could only find spare straight hinge pins part #ASC 4569 at Associated.
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Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-suspension-arm-mount-upper-resized.jpg  

Last edited by John Stranahan; 02-18-2007 at 10:49 PM.
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Old 02-18-2007, 10:38 PM   #949
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Hey John have you thought about a cantiliver front suspension setup like the ones common on 18th scale cars like the hpi micro rs4 or the xray M18?
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Old 02-18-2007, 10:43 PM   #950
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I have looked at that type of suspension. The shocks are toward the center of the car. That is where the GTP bodies are lowest. No room to put a real shock there vertically. The mini-z and such cars that use this suspension don't have a real shock just a telescoping plastic tube. More of a spring holder than anything. I found through experiments that the key to preventing blowovers on a bumpy straight is good hydraulic damping. Longer front travel did not work. Sway bar plus softer spring did not work. Longer travel kingpins did not work. You may not experience this problem at all though if the track is smooth or if the motor does not drive the car over 50 mph on the straight. We did consider bellcrank driven horizontal shocks perpendicular to the frame. We are in the over 50 mph zone with a Novak 3.5 and 6 cell equivalent on a 1/8 scale track.

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Old 02-18-2007, 11:39 PM   #951
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Wow, that's crazy fast. Must tick off a lot of the nitro guys. I'd like to see that sometime. Did you decide against the bellcrank idea because its complexity outweighed the benifits?
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Old 02-19-2007, 12:03 AM   #952
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I did some other experiments as well. What I found is the shock will work the best when it is as close to the wheel as possible. This will give it more travel and less suspension friction (stiction) from any linkage. I tried the shock in its current location and it fit. That is a good reason by itself. It also puts the shock in the front wheel tub which is taller. I tried a less direct shock attachment to the upper arm. This worked well up to a 4.5R. The 3.5 and the 3 link is a bit faster and required a better shock setup. Yes it is as fast as the 1/10 Nitros on the straight, I had a little trouble turning today due to a mechanical problem. The current front suspension improved my fastest lap times .4 seconds over the previous modified Associated front suspension under the same track conditions. That is a lot of improvement.
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Old 02-20-2007, 09:59 AM   #953
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Boosted - you don't have to go as complex as John has been going to keep up with the 1/8th scalers. We'd been doing it regularly with 6-cell Mod (usually 9 to 10 turn) and putting in times very comparable to 95% of the 1/8th scale drivers. . .for 5 minutes.

John's just taken the weaknesses that we all knew about and dealt with as inherent to the platform and either eliminated them or made them strengths.
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Old 02-21-2007, 03:38 AM   #954
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John, I got some more testing in with my Novak 3.5R last sunday.
I tried some different rollouts:
I found that at 26mm/rev it doesn't really perform. It came alive at 26.8 and When I went up to 28.0mm/rev it really screemed. It also has more rip out of the corner with that slightly taller gearing.

Perhaps with your slightly higher voltage Lipo Packs you might even want to gear up more.

I used throttle profile #1 on the GTB, with all drag brake out, minimal brake and maximum drive frequency.
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Old 02-23-2007, 07:06 PM   #955
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Mathijs-Thanks for the gearing report. I am going to have to attribute the different optimum gearing that we found on either track differences or different levels of forward traction that our two cars might develop. I may try a gear that tall one day but I have never had a motor get slow going taller and then get fast again by going taller still.

Track Report
I have been hot rodding the Ford Focus this week. Reflash, New Lowering Springs, hence the lack of activity on this thread.

We had a good practice session today. The track was clean. 65F. 3.5R Motor Temp 140F after dumping a pack. I had good grip. I was holding my own against Tony's 1/10 scale Nitro and Neils 1/8 scale Nitro. The pan car was working well.
AntiDive
A couple of problems that I solved recently led to getting my steering back. When I changed my lower A-arm mounts which have a custom drilled hole I inadvertently added a little antidive. The lower Arms were tilted down at the front. This killed some steering on corner entry while slowing. I corrected the problem. I also replaced a balky servo that had caused me grief in the last race. The car would just not turn right effectively at all. I tested it one more time as I had the antidive problem corrected. The servo was still erratic. Steering is back to very good after I replaced the servo.

The IRS hardcoated pivot balls took out almost all the slop in the front suspension. I notice that Custom Works also sells a plastic rod end and pivot ball for the pan cars. This plastic ball measured the correct size. The rod end is not as beefy as the associated part. It might be good on an indoor lightweight car.

Traxxas Jato, IRS Ball Ends
I purchased some IRS hardcoated pivot balls for my Red Traxxas Jato link ends on my 3-link suspension. They fit some ends well but were tight in some others. The rear links on my setup get quite a bit of stress in the crashes. This beefy size is probably a must. I have not had to readjust the lower links at all. The upper link got a little tight in the pivot ball area. The IRS pivot balls cured this.
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Old 02-24-2007, 11:41 PM   #956
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3-Link on Narrow Pan Car
Kevins Narrow chassis arrived with some extras (thanks). Here is the first stage of the project. The upper and lower pod plates are custom. The left and right side pod plates are Associated. Panhard bar and shocks will be in the back. I plan to setup for Lipos. If I were cutting a chassis for NiMH I think I would use 3 cell saddle packs one behind the other with cells parallel to the cars long axis. A square cell setup. This would put the cells far enough back I think. One advantage of this 3-link is that the antisquat lifts the center of the chassis on acceleration. This loads the tires very well making the rear most weight balance not as important. With the present balance it should be able to go 60 to 70 mph on a long track without a great tendencey to lift the nose.

The upper deck is made of 2 reshaped Pantoura Battery braces.

I may use the same dynamic double A-arm front end I use now by drilling new holes in the chassis so the front will be narrow, but the front suspension will have long arms for good traction on asphalt.

The wide 3-link car is working great.
Attached Thumbnails
Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-3-link-narrow-chassis-b-001-resized.jpg   Pantoura, 1/10 Pan Car, 2S LiPo, Brushless, Tips and Tricks.-3-link-narrow-chassis-c-resized.jpg  
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Old 02-25-2007, 01:56 AM   #957
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Cool keep us posted!
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Old 02-25-2007, 05:26 AM   #958
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hey guys,

I've been looking for answers from the experts here. I've been wondering why lots of pros are racing their nitros, pan cars and foam tc with small diameter foam instead of larger ones.

From my experience, both my 1/10 and 1/12 pan cars have plenty of rear end grip and traction with larger diameter tires. I am a true believer of larger contact patch yields larger traction. This can be achieved with either large diameter or wider tires.

There are many 1:1 scale example, drag racing cars, F1 and champ cars. None of them run small diameter rear tires. What do you guys think?
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Old 02-25-2007, 05:31 AM   #959
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Small tires have less rotating mass and less unwanted sidewall flex. I always see my lap times improve when the tires get smaller.
On a real slippery track I resort to bigger tires.

In F1 the rules state that the wheels may not be larger than 13 Inch, otherwise they'de opt for larger wheels and smaller tires.

In drag racing forward traction is the only concern, and than a bigger tire with more flex is probably better.
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Old 02-25-2007, 05:44 AM   #960
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well, back in the 80s where F1 cars are turbocharged, the rear tires were huge. I wonder why colin chapman or adrian newey never experimented running their cars with smaller diameter tires to lower the moment of inertia.

Anyhow, though I understand the notion that smaller diameter tires will result lower lap times, I still wonder on whether it really makes a lot of difference considering foam donut weight is already very light in weight.
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