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Old 03-07-2017, 06:49 PM   #91
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If pan cars can do it (and do it well btw i.e. 1/12 mod, wgt, pro 10 etc) why can't an independent suspension car...? I was thinking on this the other night whilst fiddling with my VTA... VTA is all about authenticity with period paint, proper looking tires and a lower power motor. Trans Am cars were a handful, hell any serious race car is a handful, rear end braking away if you lose concentration for even a split second, heavy, torque monster from hell V8's... they were/are fucking amazing! Now, vta uses wider tires, there's something towards the traction issue previously stated, along with heavier limit per rules, which also aid's traction. The lack of front brakes I didn't even consider until reading this thread tonight, so to that point I submit: use normal 4wd belted chassis. Keep all belts where they are. get a one way diff. Turn it around so that its in backwards.... no power to front wheels but has braking effect.
Think it'd work?
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Old 03-07-2017, 07:13 PM   #92
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I've asked the same question. Several years ago, I bought a Tamiya F103 GT. It had a solid rear axle but it was 2wd and regular, 190mm TC shells fit it. It was very lightweight and hard to control. Having said that, it was also a lot of fun. I still want a Rwd TC. I thought about this one:

https://www.amazon.com/3Racing-Sakur...ds=3racing+2wd

but the consensus was that this platform would not be good for anything other than 2wd drifting. Part of the problem is that 1/10 scale TCs have such small, thin tires and not much weight. Still, it's an area worth looking into in my opinion.
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Old 03-07-2017, 09:12 PM   #93
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Originally Posted by roosterreagan View Post
The lack of front brakes I didn't even consider until reading this thread tonight, so to that point I submit: use normal 4wd belted chassis. Keep all belts where they are. get a one way diff. Turn it around so that its in backwards.... no power to front wheels but has braking effect.
Think it'd work?
Thought's crossed my mind more than once. :-)
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Old 03-07-2017, 10:53 PM   #94
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The lack of front brakes I didn't even consider until reading this thread tonight, so to that point I submit: use normal 4wd belted chassis. Keep all belts where they are. get a one way diff. Turn it around so that its in backwards.... no power to front wheels but has braking effect.
Think it'd work?
It would work, but:
- it would be heavy - one of advantage of RWD over AWD is lightness. With all components from AWD, you'd lose this advantage
- it would add some losses - belt drive brakes a little even when it doesn't drive anything
- it would be hard to control, if you really use one way, or swapped for spool
- it would become AWD in reverse. That's not real advantage, but still, it's not 2WD.

I think that in 2WD, there should be no connection between axles. And in best case, even no mechanical connection between left and right wheel on the non-driven axle... Using driveshafts and inboard brakes is on the edge - rarely it was used in real cars, too (lotus 72 for example) and it's maybe easiest way to fit brakes in RC
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Old 03-08-2017, 05:28 AM   #95
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So we're basically already trying to find technical workarounds to alleviate the pain of driving a 2wd car (here: bringing brakes to the front) while still preserving the 2wd "status"

get it?!?
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Old 03-08-2017, 05:58 AM   #96
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Along with what Lonestar has stated,

You could pull a book out of the Pro-10 and Tamiya Eurocup F1 cheaters of the 90's and run traction control sensors on the front that tie in to the ESC.

- I know as I was part of that Pro10 racing scened when this happened in Germany.

Its Funny, we have raced 1/8 IC 2wd Pan and Suspension cars all these years without any sort of mechanical front brake etc. You just learn how to drive the car, and we always knew we would never reach the same potential as the 4wd cars!

Even the 2wd 1/8 Brushless buggies in France dont run front brakes.
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Old 03-08-2017, 06:00 AM   #97
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If pan cars can do it (and do it well btw i.e. 1/12 mod, wgt, pro 10 etc) why can't an independent suspension car...?
Because of their mechanical grip, you can not emulate that. They have a super low roll center and CG.

The closest you will ever get to that kind of grip with a suspension car, is with a Direct Drive Oval Car. I.e a Custom Works Dominator, or a Murfdog!
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Old 03-08-2017, 06:15 AM   #98
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Mmmk, I appreciate all of the above but still haven't heard a reason it won't work, I get the high COG, muscle cars are kinda wobbly, so I would put that into the authenticity column. I'm going to do it, I know everyone will be very concerned about how much time I'll be wasting and how it's probably the stupidist thing in the world blah blah blah (the normal forum negativity) but hell I got time. Anyone have a one way they could sell? Or know how to make a homemade dealy with a generic one way bearing?
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Old 03-08-2017, 08:20 AM   #99
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If you tried to run tc sized tires on a pan car, it wouldn't handle very well and would have low traction. Keep the wider foams on them and suddenly they work great, stick very well and can stop. It comes down to traction. The tires on tc cars are the same size as each other all around but are very narrow and all 4 wheels drive. Weight is pretty equal front to back. 2wd "off road" buggies do well on high grip tracks but again, they don't run narrow tc tires.

If you want a 2wd IRS on road car that handles well, use tires more appropriate for the job that are wider in back. You can still get foams for dirt oval 2wd that bolt right onto an RC10DS and they work great. They aren't as wide as pan car rear foams but are much wider than tc tires. They are a great compromise. A 2wd car needs more weight bias to the rear. The only tires that accelerate and brake the car need to have adhesion. There are already 2wd on road cars that are fast that don't suffer the problems being argued about here. They just don't use tc style tires.
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Last edited by fredswain; 03-08-2017 at 10:02 AM.
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Old 03-08-2017, 09:21 AM   #100
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Mmmk, I appreciate all of the above but still haven't heard a reason it won't work, I get the high COG, muscle cars are kinda wobbly, so I would put that into the authenticity column. I'm going to do it, I know everyone will be very concerned about how much time I'll be wasting and how it's probably the stupidist thing in the world blah blah blah (the normal forum negativity) but hell I got time. Anyone have a one way they could sell? Or know how to make a homemade dealy with a generic one way bearing?
You've been given plenty of reasons why it won't work (or is unlikely to work), and you've also been given plenty of examples of people's own experience of a RWD rubber-tyre cars not working.

But I don't think there is any negativity here.

We would all agree that the hobby is about enjoyment. If you will get enjoyment from building a RWD rubber-tyre car - then do it!
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Old 03-08-2017, 10:23 AM   #101
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Because of their mechanical grip, you can not emulate that. They have a super low roll center and CG.

The closest you will ever get to that kind of grip with a suspension car, is with a Direct Drive Oval Car. I.e a Custom Works Dominator, or a Murfdog!
Isn't rollcenter located exactly in pivot ball? Doesn't look extra loelw to me.
Maybe they are softer in roll, but that can be achieved in independent suspension too - Serpent X does it
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Old 03-08-2017, 01:36 PM   #102
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Isn't rollcenter located exactly in pivot ball? Doesn't look extra loelw to me.
Maybe they are softer in roll, but that can be achieved in independent suspension too - Serpent X does it
Its lower than any TC Serpent Project X or not. look at the ratio of roll center to cog!!! Either way i understand what yall are trying to do, just consider that this has been tried years ago. And although the TC seems like a great platform, it was designed as a 4wd car, if you want to convert a TC, convert a 747E, a dedicated 200mm car, onto which you can run up to 220mm and still have Independant suspension.
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Old 03-08-2017, 02:09 PM   #103
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Its lower than any TC Serpent Project X or not. look at the ratio of roll center to cog!!! Either way i understand what yall are trying to do, just consider that this has been tried years ago. And although the TC seems like a great platform, it was designed as a 4wd car, if you want to convert a TC, convert a 747E, a dedicated 200mm car, onto which you can run up to 220mm and still have Independant suspension.
Independent suspension can have rollcenter far lower than pancar style chassis. Or can you get rollcenter under chassis with live axle?

Project X copies link styled suspension, with roll and heave damped independently on each other.. It doesn't affect rollcenter

And modern F1s are 190mm and work even with rubber tires... Why TC cant? It just need wider rear tires
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Old 03-08-2017, 02:29 PM   #104
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...
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Old 03-08-2017, 02:44 PM   #105
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...yeah there have been some that have it lower, Pantoura, ART Agitator, and the PH10 to name a few. Not sure how close the new Mcpappy comes.
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