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Old 07-19-2012, 11:24 PM   #2131
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Paolo will you be in the office tomorrow?
I'm @ Timezone
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Old 07-19-2012, 11:43 PM   #2132
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Hi Guys and welcome Phil to the Snake Pits...

Serpent has uploaded some of my latest 966 TE Setups. You can check them out here:

http://serpent.com/product/903011/setups/
Paolo grazie per l'aiuto il mio amico
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Old 07-20-2012, 05:05 AM   #2133
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Yes...... Rumors. I can tell you that there is no new car in September. Our 2012 car is the 966 TE.
Andrea, non credere a tutto quello che senti in Italia.
OK, grazie.
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Old 07-20-2012, 05:50 AM   #2134
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I have a question for the racers in here. Technically, this could be asked of any brand car... but I figured there would be a greater majority of posters in this thread who had seen the RedRC "Pro Tips" series w/ Michael Salven. I don't race gas on-road anymore, only electric... and predominantly pan-cars(12th, WGT etc). So, you will have to bear with me here. I was watching the first Salven video: http://www.youtube.com/watch?v=pjecRkYoT6M

At about the 5 min mark or so, after he lubes the front driveshafts and re-installs them, he goes about re-attaching the upper arm mounts to the front bulkheads. Salven places a 2mm shim under the front of the upper arm mount. This effectively tilts the upper arm hinge-pin/axis of rotation backwards. Being a pan car racer, I am very familiar with reactive caster... it is a very useful tuning aid and can be the difference between a great car and one that is hardly drivable. However, the typical dynamic caster that is used on pan-cars sets the upper arm rotational axis at an angle forward... not back. So what Salven is doing is effectively using "reverse" reactive caster from what is typically used on pan-cars, etc.

Now, what confused me was Salven's subsequent explanation for this modification. He mentions that the "reverse" dynamic caster gives "better turn-in" and responsiveness @ corner entry, without sacrificing steering later in the corner.

This is basically, verbatim, what "normal" reactive caster does. When the upper arm axis of rotation is angled forward, the caster angle decreases as the front suspension compresses. Thus, at corner entry when you lift off the throttle or tap the brakes, the load is transferred to the front suspension... compressing it and reducing the caster angle(standing the steering hub up in a more vertical configuration) and giving more steering at turn-in. At corner exit, however, as the suspension begins to extend, the caster angle progressively increases... thus aiding in corner-exit steering.

By using the "reverse" reactive caster, Salven is setting the car up so that it gains caster as the suspension compresses. This makes sense, as a few seconds later he mentions that this allows him to run a smaller static caster angle, as he hates the way the car feels with lots of caster. But... if the front suspension caster angle increases as the suspension compresses, you will end up with lots of caster @ turn-in, making the car sort of numb and un-responsive... and much less caster @ corner exit, taking away some of the steering there as well.

With the electric pan cars, we have only ever used the "normal" reactive caster. Can someone explain the reasons for using the "reverse" reactive caster on any car? All I can come up with is that it would make a twitchy over-steering car easier to drive... But that is basically the opposite of what Salven is saying. So... is Salven's explanation incorrect? Or is there something I am missing here?
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Old 07-20-2012, 06:24 AM   #2135
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Originally Posted by JamesL_71 View Post
I have a question for the racers in here. Technically, this could be asked of any brand car... but I figured there would be a greater majority of posters in this thread who had seen the RedRC "Pro Tips" series w/ Michael Salven. I don't race gas on-road anymore, only electric... and predominantly pan-cars(12th, WGT etc). So, you will have to bear with me here. I was watching the first Salven video: http://www.youtube.com/watch?v=pjecRkYoT6M

At about the 5 min mark or so, after he lubes the front driveshafts and re-installs them, he goes about re-attaching the upper arm mounts to the front bulkheads. Salven places a 2mm shim under the front of the upper arm mount. This effectively tilts the upper arm hinge-pin/axis of rotation backwards. Being a pan car racer, I am very familiar with reactive caster... it is a very useful tuning aid and can be the difference between a great car and one that is hardly drivable. However, the typical dynamic caster that is used on pan-cars sets the upper arm rotational axis at an angle forward... not back. So what Salven is doing is effectively using "reverse" reactive caster from what is typically used on pan-cars, etc.

Now, what confused me was Salven's subsequent explanation for this modification. He mentions that the "reverse" dynamic caster gives "better turn-in" and responsiveness @ corner entry, without sacrificing steering later in the corner.

This is basically, verbatim, what "normal" reactive caster does. When the upper arm axis of rotation is angled forward, the caster angle decreases as the front suspension compresses. Thus, at corner entry when you lift off the throttle or tap the brakes, the load is transferred to the front suspension... compressing it and reducing the caster angle(standing the steering hub up in a more vertical configuration) and giving more steering at turn-in. At corner exit, however, as the suspension begins to extend, the caster angle progressively increases... thus aiding in corner-exit steering.

By using the "reverse" reactive caster, Salven is setting the car up so that it gains caster as the suspension compresses. This makes sense, as a few seconds later he mentions that this allows him to run a smaller static caster angle, as he hates the way the car feels with lots of caster. But... if the front suspension caster angle increases as the suspension compresses, you will end up with lots of caster @ turn-in, making the car sort of numb and un-responsive... and much less caster @ corner exit, taking away some of the steering there as well.

With the electric pan cars, we have only ever used the "normal" reactive caster. Can someone explain the reasons for using the "reverse" reactive caster on any car? All I can come up with is that it would make a twitchy over-steering car easier to drive... But that is basically the opposite of what Salven is saying. So... is Salven's explanation incorrect? Or is there something I am missing here?

one thing you have understand is pan car front suspension has fixed bottom arm and the steering block pin is pivoting with the pivot ball thats why reactive caster is happen, with gas car it will not have reactive caster because top and bottom arm are moving up and down at the same time so only have static caster

Last edited by tl2111; 07-20-2012 at 06:36 AM.
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Old 07-20-2012, 07:42 AM   #2136
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one thing you have understand is pan car front suspension has fixed bottom arm and the steering block pin is pivoting with the pivot ball thats why reactive caster is happen, with gas car it will not have reactive caster because top and bottom arm are moving up and down at the same time so only have static caster
Salven specifically states that the purpose of placing the 2mm shim under the upper arm mount is to create dynamically changing caster....

??
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Old 07-20-2012, 11:57 AM   #2137
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I'm @ Timezone
Ok. I will give you a call during the later part of next week. Good luck lets have a repeat of last year! Top step!
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Old 07-20-2012, 03:57 PM   #2138
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Originally Posted by JamesL_71 View Post
I have a question for the racers in here. Technically, this could be asked of any brand car... but I figured there would be a greater majority of posters in this thread who had seen the RedRC "Pro Tips" series w/ Michael Salven. I don't race gas on-road anymore, only electric... and predominantly pan-cars(12th, WGT etc). So, you will have to bear with me here. I was watching the first Salven video: http://www.youtube.com/watch?v=pjecRkYoT6M

At about the 5 min mark or so, after he lubes the front driveshafts and re-installs them, he goes about re-attaching the upper arm mounts to the front bulkheads. Salven places a 2mm shim under the front of the upper arm mount. This effectively tilts the upper arm hinge-pin/axis of rotation backwards. Being a pan car racer, I am very familiar with reactive caster... it is a very useful tuning aid and can be the difference between a great car and one that is hardly drivable. However, the typical dynamic caster that is used on pan-cars sets the upper arm rotational axis at an angle forward... not back. So what Salven is doing is effectively using "reverse" reactive caster from what is typically used on pan-cars, etc.

Now, what confused me was Salven's subsequent explanation for this modification. He mentions that the "reverse" dynamic caster gives "better turn-in" and responsiveness @ corner entry, without sacrificing steering later in the corner.

This is basically, verbatim, what "normal" reactive caster does. When the upper arm axis of rotation is angled forward, the caster angle decreases as the front suspension compresses. Thus, at corner entry when you lift off the throttle or tap the brakes, the load is transferred to the front suspension... compressing it and reducing the caster angle(standing the steering hub up in a more vertical configuration) and giving more steering at turn-in. At corner exit, however, as the suspension begins to extend, the caster angle progressively increases... thus aiding in corner-exit steering.

By using the "reverse" reactive caster, Salven is setting the car up so that it gains caster as the suspension compresses. This makes sense, as a few seconds later he mentions that this allows him to run a smaller static caster angle, as he hates the way the car feels with lots of caster. But... if the front suspension caster angle increases as the suspension compresses, you will end up with lots of caster @ turn-in, making the car sort of numb and un-responsive... and much less caster @ corner exit, taking away some of the steering there as well.

With the electric pan cars, we have only ever used the "normal" reactive caster. Can someone explain the reasons for using the "reverse" reactive caster on any car? All I can come up with is that it would make a twitchy over-steering car easier to drive... But that is basically the opposite of what Salven is saying. So... is Salven's explanation incorrect? Or is there something I am missing here?
The tire contact patch changes with different angles on the upper hinge whether being positive or negative and will give different traction characteristics throughout the turn ...

It is easy enough to try for yourself and make your own conclusion/ theory.
Even on the bench turning the wheel left to right while creating weight transfer you can see differences in contact patch try it
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Old 07-20-2012, 04:36 PM   #2139
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Can someone explain the reasons for using the "reverse" reactive caster on any car? ........ Or is there something I am missing here?
The way 4WD 1/8 on-road gas cars are typically driven. Unlike electric cars, our cars have rear solid axles, so we make our cars change direction not just with turning the front wheels but at the same time applying throttle to place the rear end; ie. throttle steering.

Very rarely we rely on off power steering as a rear solid axle creates too much drag, so we power our cars into, round and out of corners, or at least hold on to or 'feather' the throttle to get the amount of rotation we need.
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Old 08-05-2012, 01:13 PM   #2140
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I like the body mount changes M.S and Sabrina did to their cars at the EC
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Old 08-05-2012, 06:12 PM   #2141
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I like the body mount changes M.S and Sabrina did to their cars at the EC
I saw that too. Is it to increasae front end flex ?
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Old 08-06-2012, 12:03 PM   #2142
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I saw that too. Is it to increasae front end flex ?
Well the word from M.S to me was the rear mounts are more stable and the front was for weight balance. He was trying to get more rear weight
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Old 08-14-2012, 06:41 PM   #2143
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Default Help! Looking for the Central Lola body

Hello All,

Does anyone know where I can purchase the Central Lola body manufactured by Serpent?

http://www.redrc.net/2007/02/serpent...la-body-shell/


Tried ashford, kamikaze, etc w/ no luck.


Your help is greatly appreciated. Thanks for looking.
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Old 08-14-2012, 08:43 PM   #2144
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That's gonna be hard to come by as it's been out of production for about 4-5 yrs. plus the newer shells provide more performance. Best bet is eBay and over seas. Wish you luck.
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Old 08-14-2012, 09:13 PM   #2145
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That's gonna be hard to come by as it's been out of production for about 4-5 yrs. plus the newer shells provide more performance. Best bet is eBay and over seas. Wish you luck.

Thanks again Dan. I wanted to adventure out on some old school bodies, but I guess I'll have to resort to perhaps some of the Blitz bodies.
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