My son is an AoL this year so I've been pretty hands off with his build. He's usually been more concerned with how the car looks more so than how it places though we did get 2nd place in the pack two years ago. Last year he lost in a tie breaker for the top 3 in the den and our den eventually went on to sweep the pack 1-2-3. This year he is determined to make as fast a car as possible to try to win it all. Rules are pretty loose. You have to use the axles and wheels from the kit. You have to use the block of wood in the kit. Overall dimensions and weight limits. No springs or mechanical assist devices. No bearings or bushings or washer. After that it's anything goes. We talked about what makes a good design, weight placement, aerodynamics, etc. We bought some TXchemist weights to give us the most flexibility from the weight placement. His design is a slight wedge that is almost flat. He was originally at 28+g on the FDW after adding all his weights. We decided to put his wedge on a diet. I routed the inside of the body out for him some (Not comfortable with him and the router) and removed around 8g of material for him. With two 3.7g weights on the rear drive side these are his numbers:
DFW: 23.31g
DSRW: 52.60g
NDSRW: 64.24g
Total: 140.15g (140.00 when weighted as a whole)
Wheelbase 4.8"
Rear wheel 5/8" from back of car.
There was a .15g difference when weighting the car as a whole v. weighing each wheel individually. I only have one scale so I attribute this to the blocks I use to hold the car up under the wheels not being the exact thickness of each other compared to the scale. We have some small .5g and 1.7g weights we will use to get his car up to weight at weigh ins. Probably going to remove a little more material since he will be putting some vinyl under the car for aerodynamics. Shooting for 140g and let him bring it up to weight at checkin.
There are 3 of the 19.6g (0.69 oz) bars behind the rear wheels for a total of 2.07oz and the three smaller 7g (.25oz) bars biased towards the DFW side in front of the axle.
Our track is an aluminum track and the gaps between the sections are never 100% smooth and even. The car he placed 2nd two years ago with was slow off the line compared to others but never wobbled and would always pass everyone at the bottom of the track. That car that had 4" of steer but wasn't weighted as aggressively and the rear wheel was 7/8" from the end of the car with a 4.625" wheelbase but had fenders.
Looking for feedback on his car as we make the last minute preparations for the race this weekend. Should we risk getting more aggressive with the weighting? We can always remove more material from the inside. We could stretch the wheelbase too if we think we need more stability. Unfortunately we will not be able to run the car on the track beforehand so we will have to just show up and run on race day. I asked him is he was planning on painting it and he said "Only if it will make it faster". Any feedback on if paints actually help any with wheel friction?
DFW: 23.31g
DSRW: 52.60g
NDSRW: 64.24g
Total: 140.15g (140.00 when weighted as a whole)
Wheelbase 4.8"
Rear wheel 5/8" from back of car.
There was a .15g difference when weighting the car as a whole v. weighing each wheel individually. I only have one scale so I attribute this to the blocks I use to hold the car up under the wheels not being the exact thickness of each other compared to the scale. We have some small .5g and 1.7g weights we will use to get his car up to weight at weigh ins. Probably going to remove a little more material since he will be putting some vinyl under the car for aerodynamics. Shooting for 140g and let him bring it up to weight at checkin.
There are 3 of the 19.6g (0.69 oz) bars behind the rear wheels for a total of 2.07oz and the three smaller 7g (.25oz) bars biased towards the DFW side in front of the axle.
Our track is an aluminum track and the gaps between the sections are never 100% smooth and even. The car he placed 2nd two years ago with was slow off the line compared to others but never wobbled and would always pass everyone at the bottom of the track. That car that had 4" of steer but wasn't weighted as aggressively and the rear wheel was 7/8" from the end of the car with a 4.625" wheelbase but had fenders.
Looking for feedback on his car as we make the last minute preparations for the race this weekend. Should we risk getting more aggressive with the weighting? We can always remove more material from the inside. We could stretch the wheelbase too if we think we need more stability. Unfortunately we will not be able to run the car on the track beforehand so we will have to just show up and run on race day. I asked him is he was planning on painting it and he said "Only if it will make it faster". Any feedback on if paints actually help any with wheel friction?
