: TC setup tips 101



Oblivion
26-01-2005, 08:23 PM
heres some setup tips which may help other touring car fanatics , and may even be of use to an offroad rc aswell.





area of adj..................to decrease...................to decrease
....................................understeer....................oversteer

front wheel width.........wider............................narrower
rear wheel width...........narrower.....................wider
.
.
front camber...............more -............................more +
front caster.................more +...........................more -
front toe......................more toe out..................more toe in
rear camber................more +...........................more -
rear toe......................more toe out..................more toe in
.
.
front sway bar............soften.............................stiffen
rear sway bar.............stiffen..............................soften
.
.
front spring rates........soften..............................stiffen
rear spring rates.........stiffen...............................soften
.
.
weight distribution
front.............................decrease.........................increase
rear..............................increase..........................decrease
.
.
front section width.......increase..........................decrease
rear section width........decrease.........................increase
front tread depth.........decrease.........................increase
rear tread depth..........increase..........................decrease


__________________
Your clutch technically can't be put on backwards. You will either set it up for leading edge engagement (the pins are in ther rear of the clutch shoes: #1: which will make them engage quicker, usually giving a slower take off) or trailing edge engagement (pins are in the front of the shoes: #2: which will let them ingage later when the engine is producing more torque, which usually gives a quicker take off).


http://users.esc.net.au/~oblivion/pics%20for%20posting/clutchshoes.JPG

R/C car engines rotate CCW (counter clock-wise) As the engine increases revolutions the leading edge of the clutch (picture 1) catches on the clutch bell and aggressively transmits the power from the engine to the clutch bell. This power is then distributed through out the car's drive train and eventually to the tires... <Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;</Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;
The stock clutch setup loads the engine with the strain of trying to accelerate 1.5 - 2.5kgof car and at the same time the engine attempts to quickly accelerate to reach it's higher power band. 2-Stroke engines increase power output as the RPM’s increase. So if you want to use more of your engines available power when you need it th
<Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;</Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;
e most (quick acceleration on the corners). You need to let the engine engage at a latter time when the RPM's are higher and when the engine has more available power to accelerate the vehicle. <Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;</Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;
<Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;</Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;


For the clutch setup that is showed on picture (2) you pull the clutch shoes off the flywheel and flip them around and re-install. This mod basically changes the power transfer when accelerating because now the trailing edges of the shoes engage the clutch bell. This allows the clutch to slip a bit for the engine RPM’s to build and jump starts the torque level when accelerating from the corners


shock mount position / shock angle


What it does: Like the Camber Link Roll Center adjustment, many cars allow you to change the angle of the shock. By changing this angle you can make the shock feel a little stiffer (the shock angled in or “laying down” more) or a little softer (shock standing more upright) as the car rolls.

How to change it: It is very simple, all you need to do is change where the shock mounts to the shock tower in relation to the Lower Arm mounting position.

When to change it: If you want a little more initial turn in but less steering in the middle of the turn, lay the front shock down more or stand the rear more upright. If you want a little more on power steering, lay the rear shocks down more or stand the fronts more vertical.

Tips: Putting the rear shocks too close to upright can cause the back tires to skip a bit going around turns. Laying down all the shocks can slow the car down even though it feels like it has more bite. The more prepared the track is, the more you can lay down your shocks


Suspension:

- Caster -- Caster is the angle of the axis that the front hub carriers pivot on looking at the side of the chassis. More positive caster will allow more weight to be transferred to the front of the chassis off throttle or under braking. This promotes more steering. Positive caster also allows the wheels to lay back a little more when they are turned one way or the other. This increases negative camber, which also provides more steering through the corner. To adjust front caster you simply move the caster spacers that are located on the upper suspension pin next to the upper suspension arm. By moving the spacers to the rear of the arm, (pulling the arms back towards the rear of the chassis) you are adding more caster and you should get more steering from the car. By placing the spacers toward the front (pushing the arms toward the front of the chassis) you reduce the caster and will take some steering out of the car. This usually makes the car a little more drive-able and less sensitive out of the corners. Start with all of the shims placed to the front of the arm then move one shim at a time, from each side, back to the rear as you need more steering.

- Re-active Caster -- Re-active caster is adjusted by using the re-active caster wedges that are supplied in the kit. By changing the angle of the upper suspension mount the caster will change as the suspension is compressed. Remember that if you are using the 3 degree upper mount and a 0 degree lower mount then you already have re-active caster built in. Adding the wedge will make it react even more. By placing the thicker side of the wedge toward the rear it will kick up the backside of the upper suspension mount thus taking away caster as the suspension is compressed. This a fine tuning adjustment that should be one of the last items to adjust. A good base starting point for re-active caster is to use the stock 3 degree lower suspension mount and the stock 3 degree upper suspension mount and no re-active caster wedges then use the wedges as they’re described above as needed.

Chassis Tweak

- Basic Set-up Procedures -- Start with removing the wheels and shocks. Next, disconnect both sway bars. Now set the chassis on a flat surface such as set-up board. Check for binding in the suspension components. Everything should move freely. Check down stop settings and length of the shocks to make sure that left and right sides are equal. Install all shocks and wheels and set desired ride height. Now check chassis tweak on a tweak station. After setting the tweak flat, hook up the sway bars and re-check tweak. The car should be ready to race. A properly set-up chassis will provide consistent performance every time.



Drive train

- Differentials -- The differentials can be adjusted to get the car to react differently in the corners. A tighter front differential will typically give the car a little bit of push going into the corners. A tighter rear differential will allow the rear end to come around a little quicker going into and coming out of a corner. Use small adjustments and do not adjust both of the differentials at the same time. This could cause the chassis to change too much getting a worse result than before. On tracks with a high bite surface you can run both diffs a little tighter than on a track with less traction. Also, larger tracks can also allow you to tighten a little on both diffs. The reason behind this is the car will be under acceleration a lot more on larger tracks and the tighter diff adjustment will keep the power from unloading as much allowing you to get more power to the ground.



Radio Set-up

- Exponential -- Expo is an adjustment that is made to make your car feel more responsive to your input. You can de-tune the Expo to make it less sensitive. Most radio systems have the ability to adjust from –100% to +100%. You should start around 0% and then adjust one way or the other in small increments. It’s usually better to start around –15% to –25% and then slowly work up to 0% from there. It is not totally necessary to use a sensitive setting. If you are comfortable with a less sensitive setting and are driving consistently then don’t force yourself to try and drive a car with more positive Expo. Most drivers never use any thing over 0%, but there are some very good drivers who do use positive Expo.


Maintenance

- Differentials -- It is recommended to rebuild your differentials between race days. This will give you the most consistent and reliable performance from your diffs. The main thing to do when rebuilding your diff is to clean off all of the grease and dirt that has collected onto the components with denatured alcohol. Check your pressure rings for deep grooves. If the rings are grooved and notched then this will give the diff a very rough feel and will not operate very consistently, flip them over or replace them. The hardened diff balls that come with the N. 4tec Pro kit are very tough and last quite a long time. You may replace the diff balls at least once a season. When assembling the diff use a good diff lube for the diff balls and a thrust bearing grease on the thrust bearing.



Tires

- Chassis Handling -- Tires are the single most important part of chassis tuning. Without the right tires it may be impossible to get your car to handle well. A good idea is to see what the faster racers at the track are using. Get some ideas from them on what works well on the front and what works well on the rear for that particular track. Start there and then use a good base set-up on your car. Try to get the best performance that you can through tires first without making adjustments to the chassis. When you get to point where the car works good and is consistent then it’s time to start fine tuning the handling with the chassis adjustments. A good base set-up on the chassis is very important. This will be different from person to person so remember that the more experience that you have with the car on the track the more you will know what a good base set-up is, so get out there and practice![/b][/b][/b][/b][/b]Edited by: Oblivion

Oblivion
26-01-2005, 08:32 PM
shock building tips


Pre-lube the O-rings in the bottom of shock bodies; Fill the shock body with oil close to top of the shock body allowing room for the shock bladder. Move the piston up and down (slowly) allowing all of the air bubbles to emerge from the bottom of the piston. Let the shock stand vertical, fully extended, until the shock body is rid of all air bubbles. Install the shock bladder into the shock cap and apply a little bit of oil around the outer ring of the bladder to prevent tears. Thread the cap on the body until it is snug. Push shock shaft up into the shock body then release. The shaft should go all the way up into the body and then slowly start to come back out. Make sure that the shock on the left side of the chassis has the same amount of shaft rebound as the shock on the right side of the chassis. It may take a couple of tries to get these results, but after a couple tries it will become much easier. Also, when threading on the rod end, make sure that the left and right hand shocks are the same length (this is very important).<BR style="mso-special-character: line-break">


Another good tip is to place an extra o-ring on the shock shaft inside of the shock under the piston to limit down travel. I also shortened the shock length a bit to limit it some more by screwing in the ball ends a bit more. I have about 1/8 inch from level on my droop measured from the end of the arms. I run my car low enough that it doesn't have much body roll anyway. What you are effectively doing when you take out the droop, is allow the chassis to have free movement to the bottom of the shock travel, but when it bottoms out the body roll is limited because the full weight of the rising side is now trying to hold the car down and limits body roll. Kind of like leaning out when sailing a Catamaran


Less droop allows the suspension to recover faster due to the decreased shock travel. This means the car is more stable in swtichbacks, because it does not have as far to go to reach a neutral position before changing directions. What you would see with a lot of droop, is the car getting upset when you try to change directions rapidly, because you are trying to transer the weight all the way from one extreme to the other before reaching neutral which means that the car is essentially acting as if you were entering a corner too fast and too late<Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;</Ohttps://www.ausrc.com/forum/smileys/smiley17.gif&gt;


Bodys
Shorter more compact bodies, like the Ford GT40, or the Nissan Z body are good for small tight tracks. Tracks with a little more speed and some sweeping turns will require a bit longer body for stability. This is where bodies like the Stratus, Mercedes CLK DTM, BMW M3 etc. really work well. Always use the side dams on your wings. They help stabilize the car. If you mount your body slightly forward will give you more forwrd bite and mounted more to rear gives you more rear bite(really only works for protoform bodies, since they don't have wheels marked so closely)<Ohttps://www.ausrc.com/forum/smileys/smiley17.gif</Ohttps://www.ausrc.com/forum/smileys/smiley17.gif


Edited by: Oblivion