Pink med on the rear left, SE gold on the rear right. fronts depend on your track, we have terrible carpet (lots of tape) but its silly grippy, i have to run 52's with superglue on the edge of my front left to give even less grip.
put some washers (1mm - 2mm) under the front screw of your a arms on the front. this will help keep the car straight.
with mardave v12's its all about right tires the rest is luck (not getting stuck in crashs)
and luck if your silver can motor lasts more than 3 meetings.
we all changed to the ezrun brushless systems (35A) got them a year ago 5 of the systems we bought (£50 each) are still running fine with no problems, if u was to try brushless i recomend these systems.
also this info on another site has always helped me.
Tyres
The tyres are one of, if not THE most important things to get right if you want your car to handle well. For carpet racing, I would recommend UFRA SE medium or UFRA Pink Soft rears and UFRA pink medium or UFRA Jap Medium fronts. The fronts work better when they are trued to about 49mm, and used until they're worn almost to the rim. Also let them wear in, so they are coned (smaller diameter on outside than inside). You can also tune them with super glue. To do this, put super glue on the outside wall of the front tyres, making the tyre wall go hard. This gives the tyres less flex, and therefore less grip. Apply more superglue for more understeer. You can also put a small blob of glue on the outside edge of the contact surface of the tyre if gluing the walls doesn't give you enough understeer. For the rear tyres, I find these tend to work better when they are about 53mm in diameter. (although I true them to 56 and use them 'till they're about 49!). You can put grooves in the rear tyres using a hacksaw blade. This enables them to flex more, and thus gives more grip. Doing this also reduces some of your front end grip.
Front Suspension
Firstly, turn your wishbones upside down, in order to lower the front of the chassis. You should aim to get the chassis as level as possible. If the back is higher than the front, the car will tend to understeer. If the front is higher, the car is more likely to oversteer (spin out). Next, put washers/spacers of some sort under the front of the wishbones, so the kingpins are angled backwards slightly. Raise the front of the wishbones by around 2-3 mm. This gives the front end positive castor, which will reduce the chances of the car spinning out on corner exits. It will tend to give the car more mid corner steering, but less on entry and exit
Rear Suspension
You should have your rear springs relatively soft/loose. Adjust the nuts so that the chassis 'sags' about 1mm below the rear edge of the motor pod when the car is at rest. If, when you pull away the car pulls to one side, but later straightens up, you can cure the problem using the rear suspension. If the car pulls to the right, tighten the right hand nut, and loosen the left one a little (looking from back of car). Do this in 1/4 turn increments until the car pulls away straight. If the problem persists, consider replacing the spur gear, as they wear out. Fit ballraces to the rear axle; they make your car a little faster, as there is less rolling resistance!
Drive
Use a smaller pinion gear for more acceleration, and a larger one for more top end speed. A 14T is a good size to start on, as I find it works well on most track sizes and shapes. Bear in mind that you may wish to increase pinion size as your rear tyres wear out. Smaller tyres will give you more acceleration than large ones. However, I wouldn't recommend going up/down by more than 1 tooth in this situation. There should be a little play between the spur and pinion, in order to get a smooth drive. If the mesh is too tight, it will ultimately slow your car down and make the motor hot. Do not have too much play or else the spur will strip easily. If you find the pinion/spur makes a lot of noise, boil some water, and leave your spur gear in it for 5 mins. This softens the plastic, making your car sound smoother!
Bodyshell
You will be surprised at how much difference the bodyshell will make to the handling of your car. I would recommend any of the following, as they seem to make the car fairly well balanced;
ABS; peugeot 205, ford fiesta, any of the ABS vesions of the shells listed below
Lexan; Clio mk1 (my favourite), wide body 205, toyota starlet, BMW mini, peugeot 206
Extra Tips
Fit a front bumper made from GRP or carbon fibre to protect you king pins and stub axles. A bent pin/axle will dramatically affect your cars handling.
Try replacing your body mounts with front and rear associated tc3 posts. This way, your body will never come off during a race.
If you have an electronic speedo, remove the top plate and place the speedo where the receiver should be. Put the receiver ontop of the steering sevo, and use a tube for the aerial. Use fibreglass tape to hold you batteries in, or alternatively the mardave cobra battery mounts do the job well.
Paint your shell bright colours. I find this helps me drive because the car doesn't blend in with the carpet/scenery, so you can see it and other drivers can see you more easily too.
It's surprising how many people are baffled as to how I (and others) get a hot-rod to go so fast. All I can say is that I make sure the motor is clean, and that my batteries are in good condition (I'd recommend geting 3300's or 3700's). As long as you have a half decent esc, there's no reason why your car shouldn't be as fast as mine or anyone elses in a straight line.
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