What is Tweak?
Tweak is the adjusting of the shock pre-loads to get all 4 tires touching the ground with equal pressure. If one side has more pressure than the other, this will cause your car to not handle consistently turning left and right. In other words, your car will be Tweaked.
Tuning with Tweak
First, I would suggest getting a tweak station, similar to MIP’s unit. To adjust Tweak on a Touring Car, a few minor checks need to be made first. Make sure all the suspension parts are free and are not binding. Also check your turnbuckles for correct length. Disconnect the Anti-Roll Bars and place the car on the tweak station, making sure the car is centered. Now (assuming you placed the front on the swing arm), push down on the front and rear of the car to settle the suspension. Look at the bubble; it should be centered on the gauge. If it is, Tweak is good. If it isn’t, Tweak is off and needs to be fixed. If the bubble is to the right, you need to add more pre-load to the LEFT front (or RIGHT rear) of the car. If the bubble is to the left, you need to add more pre-load to the RIGHT front (or the LEFT rear) of the car. Once you’ve corrected this, rotate the car and do the same thing to the rear.
Now, re-attach the Anti-Roll Bars (if you are using them). This MIGHT upset the Tweak of the car. Put the car back on the Tweak station and re-check it. If is off to the left, remove the right Anti-Roll Bar Mount and lenghten it slightly and then re-attach. If it off to the right, remove the left Anti-Roll Bar Mount and lengthen it slightly and then re-attach. Do this until you get the Tweak bubble in the middle of the gauge.
Tweak for pan cars is a bit different. You can use the Tweak Station or you can use the penny trick (the penny trick is a little less expensive!!!!) To Tweak using the penny trick, first set your pan car up on a flat surface in race ready trim. Now, place one penny on each front tire, but not quite in the dead center. Place it slightly forward of dead center. Find a center point under the front of the chassis and take an Xacto (or other pointy object) and lift SLOWLY. If both pennies fall at the same time, your Tweak is good. If the left one falls before the right, slightly tighten the right Tweak screw (located on the T-Bar). If the right one falls first, slightly tighten the left Tweak screw. The same system can be used to adjust Tweak on 1/12 scale cars.
Back to the RC Suspension Tuning Guide.