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Old 07-16-2013, 03:00 PM   #2041
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Thanks Eunique, I tried looking there already but unfortunately their belts reference starts at 144, I think the front belt is 138.
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Old 07-17-2013, 02:59 AM   #2042
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Ok one more question
In the first pic i show you the camber that i have when steering is straight.So about -5 deg.
Now in the second picture i am in full lock and the camber is on the inside wheel. About -1deg now.
On the final picture the steering is the same as in the second but now the camber is on the outside wheel. As you can see it is -10deg
So,is this normal and if yes why does it happen ? I couldn't find it anywhere on the net . Is it because of the caster or what ?
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Old 07-17-2013, 09:23 AM   #2043
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^there are even more variances than that. Caster is part of the equation. And variables in the steering geometry are other factors...and therein lies part of your suspension tuning. There are some tradeoffs and compromises that you will ultimately decide on. When you are in a drift, the suspension loads on the outer chassis and unloads on the inner and completely changes your camber as well...and when u measured it I'm not sure if you had the battery in place and compressed the springs at least once so that the car is at ride height.
In any case adjustments in camber do play a role and will ultimately depend on you to where you want the compromise to be and set it to how you like it.

On another note, some r/c drifters set their camber to the "looks" of their wheels in relation to their body and "learn to drive" it and compromise it that way. Its a lit to do with compromising between grip and slip.
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Old 07-17-2013, 01:43 PM   #2044
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Also if you are running on an abrasive surface the more negative camber run wears the tire out sooner. Eventually the tire will wear flat again.
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Old 07-17-2013, 02:24 PM   #2045
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Thanks guys so more caster will mean that more of this effect will happen ? Do the extra caster alum hop up parts for D3 help really ? So eunique could please tell me more about these compromises ? I want to setup my car for more grip how should my camber be now ? Please explain to me
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Old 07-18-2013, 04:30 AM   #2046
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Could someone please tell if there is any issue with the spur gear touching the body? I have Mazda and the front looks to very low to make me think it will touch the body. I would like really to get a d3 to try this counter. Ties anyone find any problem with the spur gear?

Thanks
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Old 07-18-2013, 06:15 PM   #2047
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Originally Posted by FoiVoS_ View Post
Thanks guys so more caster will mean that more of this effect will happen ? Do the extra caster alum hop up parts for D3 help really ? So eunique could please tell me more about these compromises ? I want to setup my car for more grip how should my camber be now ? Please explain to me
Less camber means more contact with the surface which equates to more grip.
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Old 07-19-2013, 01:46 AM   #2048
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So how much should be the optimum for max grip theoretically ?
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Old 07-19-2013, 09:39 AM   #2049
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Originally Posted by freakyfreakyflo View Post
Could someone please tell if there is any issue with the spur gear touching the body? I have Mazda and the front looks to very low to make me think it will touch the body. I would like really to get a d3 to try this counter. Ties anyone find any problem with the spur gear?

Thanks
I have a Lexus LFA body and a Silvia S15. Both are low slung in the front and clearance is tight on both. But they sit just fine. You could always go to a smaller spur if it became an issue.
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Old 07-19-2013, 02:08 PM   #2050
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So how much should be the optimum for max grip theoretically ?
Zero camber will give you the most grip, however most people run -2 camber. This will help prevent the tire from catching an edge on rough or uneven surfaces.
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Old 07-19-2013, 02:31 PM   #2051
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Thanks guys so more caster will mean that more of this effect will happen ? Do the extra caster alum hop up parts for D3 help really ? So eunique could please tell me more about these compromises ? I want to setup my car for more grip how should my camber be now ? Please explain to me
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So how much should be the optimum for max grip theoretically ?
Ok, probably need to back up a little here. You're asking good questions and making great observations, but it seems like you may have jumped past the question of what is causing the problem(s) that you are trying to solve, and went straight into the details of how to accomplish specific changes. I can assume the problems that you're wanting to fix, but your line of questioning is more likely to make those problems worse.

It takes awhile for new CS drivers to become comfortable with the fact that massively reduced traction is a fundamental necessity. The concept is very easy to understand, but that understanding doesn't help as much as one would think when the controller is in your hand. It takes drive time, and lots of it. CS drifting is all about being able to anticipate how the car is going to respond to your control inputs. The limited total traction and momentum of the car creates a relatively long delay before the effect of those inputs are fully realized. Most often, if the inputs were too excessive, it will be too late to correct by the time the driver sees it. Driving in "Reactive mode," is like chasing one's tail here. Every correction does far more to generate the next undesired maneuver, than it does to fix the one you're currently seeing. Again, it takes a lot of drive time to be able to get a good feeling for when and how much control inputs are needed to achieve the desired result.

The D3 CS has been specifically designed for reduced total traction. But traction is a dynamic thing and is highly tunable for CS cars. For good or bad, the D3 offers the ability to tailor each wheel's ground contact angle (camber) under different driving conditions (leading/trailing wheel, steering angle, under acceleration/deceleration, and when neutral). As your pictures show, 10 of caster produces a significant amount of steering-angle-dependent camber. By design, this makes the leading front wheel contact patch larger than the trailing wheel. This helps keep the car in a drift by putting more straight-line traction on the front wheel that is nearly inline with the car CG. More importantly, it also reduces straight-line traction to the trailing front wheel, which hugely reduces the driver's ability to straighten the car out while in a drift. Another effect of this is that the sharp line of contact on the trailing front wheel generates greater lateral traction than the leading wheel, so it behaves a bit like a drag rudder, particularly when off throttle, increasing the tendency to spinout on slight deceleration. Furthermore, the front motor position and rather sporty 2.14 stock CS ratio make the D3 exceedingly tail happy for new drivers. Their natural desire is to increase front traction and steering angle to increase their ability to "Catch" the car before it spins out. What they often don't realize until later is that these "Improvements" tend to make the car even more prone to spinouts, as it magnifies the effect of their preceding inputs.

Now to the questions:
Yes, increasing the caster will increase the effective range of camber change. Whether this is better or worse is subjective and depends on a number of things. However, 10 of caster is already too much for this car in stock trim IMO. Increasing the caster on a largely stock D3 will make it twitchier, even more prone to spinout, and more prone to drift lock (Impossible to transition). Increasing the caster will increase the performance envelope of the car, but it's important to make a distinction between increased capability and the improvement/elimination of undesired behaviors.

Yes, the various hop up parts do help, but it also depends on your desired objectives. Admittedly, some are mostly bling, some improve performance, but IMO, most are beneficial in that they increase/improve the ability to tune the car. For me in some cases, it was enough that the part simply made it easier to work on (clearance holes, threaded aluminum vs. self-tapped plastic, etc...). The list of hop-up parts that actually and completely fixed problems is extremely short. In many cases, installing a hop-up would reveal that another hop-up was required to fully realize the improvement.

For the static camber setting up front, most people will try to adjust for the largest steering angle at the leading wheel, without have ridiculous ackerman. Then, with the wheel turned to full inside lock, adjust the static camber so the wheel sits flat on the ground. Then turn full lock the other way and adjust the other side. Only adjust your suspension when the car is at ride weight and height.

Lastly, the value in dropping the CS ratio on this car cannot be overstated. Although the D3 came with a 2.14 ratio, it was not designed for it. An entry level, budget CS drift chassis, with 10 of caster and a 2.14 CS ratio is rather ridiculous, especially for an already tail-happy FM chassis. IMHO, 3Racing did this intentionally to drive buyers to purchase all the upgrades necessary to have any chance of a satisfactory driving experience at those values. It's rather ingenious and it worked on me like a charm.

Swapping out the center-rear 22T pulley with a 19T will drop your CS ratio to 1.85, and you can keep all the stock belts. You can also drop the 22T down to 18T to achieve 1.75. The rear belt still fits, but you'll need to put 3-4 mm of spacers under the rear tensioner to get it tight enough. Either change will dramatically improve your ability to transition and to avoid spinouts.
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Old 07-20-2013, 02:31 AM   #2052
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Thanks a lot Caseymacgyver . You cleared up the things for me. I will buy the pulleys as soon as i can and reduce it to 1.85Cs ratio. Now i am waiting for the FOW and the 55o angle mods to arrive . Well as it looks like i need to learn a lot more things in order to finely tune my baby My stock as far D3 is very prone to drift lock . I can assume that's because of the hight CS but until i can reduce what would actually help the problem ? I am trying to be gentle with the throttle as far as i can but still when i want it to make fast transitions it takes A LOT of time and i 50% have Drift lock
Thanks in advance !
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Old 07-21-2013, 08:42 AM   #2053
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Thanks a lot Caseymacgyver . You cleared up the things for me. I will buy the pulleys as soon as i can and reduce it to 1.85Cs ratio. Now i am waiting for the FOW and the 55o angle mods to arrive . Well as it looks like i need to learn a lot more things in order to finely tune my baby My stock as far D3 is very prone to drift lock . I can assume that's because of the hight CS but until i can reduce what would actually help the problem ? I am trying to be gentle with the throttle as far as i can but still when i want it to make fast transitions it takes A LOT of time and i 50% have Drift lock
Thanks in advance !
Hi FoiVoS...like caseymacgyver said...it will take a lot of practice...try not to get frustrated with it. Just keep practicing, then some more, then some more. I turned my throttle to 60% on the transmitter..then gradually go up as u get more used to and comfortable with it. it took me a while...and I'm still not even good with it. But I like to practice and have fun with it.
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Old 07-21-2013, 02:08 PM   #2054
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Well i am trying to find a shop to buy my pulley . Does it need to be from aluminum ? Anyways i cant find a 19T .. only a 18T but i got some 2mm spacers . Will these make the belt tension ok ?
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Old 07-22-2013, 08:13 PM   #2055
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Anybody have a 13t pulley that lives close to Illinois? I smoked a front belt which in turn melted the teeth off the pulley. Rd.3 of The Chi-Town Drift comp is this Sunday and I would like to have both Sakuras there. I have the parts on order from TQ Racing but I'm not positive they will be here in time.
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