Weight distribution

[Cubscout Dad]

I have read the forums and see people talking about the front weighing .6oz, more weight to the DFW side ECT.. I have a 3oz behind the rear axle and 1.2 oz just in front of the rear axle and that pocket is larger then the weight so I can move the weight around to find the sweet spot. My question is where is that sweet spot. Right now my DFW weighs .6oz and each rear weighs around 2.3 oz ea. My COM is right about .6inches in front of the real axels.

[email protected] if it is a secret

Thanks

 

[Crash Enburn]

I believe that unless you can spend a bunch of time tuning, you won't find the magic weight position to eke out that last thousandth of speed. Your weights as you have them listed sound like you've pretty well nailed it.

However, f you are running on a wooden track instead of an aluminum one, I'd recommend moving the CoM forward a bit to get closer to 3/4" - 1" to provide a little more stability on a rougher track while giving up very little potential speed.

 

[TRE]

1.8 to 2 oz behind rear

 

[bracketracer]

Something seem kind of skewed in your numbers there Cubscout Dad? You're adding 4+ oz of weight which would be right if the body is light like it should be, but with 3 oz behind the rear axle the car should be sitting on it's rear bumper practically. What does the body look like to end up with those weights? Is it really heavy in front of the front axle or something?

My baseline weighting usually starts around 15-17g on the DFW and I split the rest almost evenly in the rear with the NDRW biased about 2-3g heavier than the DRW.

 

[Cubscout Dad]

I will post some pics, the COM is .6" in front of the real axels. The rear axels are .9" in from the back of the car and fronts are 1" in from the front. I guess that will make my car the fastest one then.

 

[Obsessedderbydad]

I'm going to take a guess that his rear axle isn't as back as far as ours are Bracket. I've seen cars like that with a lot of weight in the rear, but it's possible because their wheels are more forward than ours.

 

[Crash Enburn]

I figured the same, but also figured that this is a scout car, so I put the emphasis on where the CoM lies now.

For future reference, Cubscout Dad, move the rear wheels back so that the axles go in 5/8" from the back end of the car. You can do this either by drilling your axle holes (use #44 drill bit), or you can cut one end off the block and glue it to the other, moving the slots back that way.

Repeating my advice from above: if you're running on an aluminum track, your 0.6" CoM is great. If you'll be running on a wooden track, that CoM is very likely too aggressive, so move the weight forward a little to get the CoM in the 3/4" to 1" range.

 

[Cubscout Dad]

Here is the car with 3.0 oz behind and 1.2 oz in front of the axles w/.6 com

 

[Rocket car]

Looks good!! The next time drill those back axles 5/8" from the back of the car and you will be even faster!

 

[Cubscout Dad]

Had our pack race today and on a 42' Best track ran 2.98, 2.98 2.96, 2nd place car ran a 2.99. going to districts but barley bet a car with all stocks parts with some work done to it. How do you gain .01 sec to be safe at the next level?

 

[BulldogRacing]

Build 5 cars and follow all the advice on here you can. Rocket gave you a great tip above. Race all the cars in a home race to see which one will represent teem Cubscout Dad.

 

[GravityX]

Purchase non-stock parts, go with an oil prep, assuming you are currently running graphite. Get some good axles. Lathe turned wheels, etc... All these things mentioned will get you faster, but it depends on how far you want to push beyond the stock parts. I'm sure some other guys will chime in, as I have not used stock parts in quite some time.

 

[BulldogRacing]

Purchase non-stock parts, go with an oil prep, assuming you are currently running graphite. Get some good axles. Lathe turned wheels, etc... All these things mentioned will get you faster, but it depends on how far you want to push beyond the stock parts. I'm sure some other guys will chime in, as I have not used stock parts in quite some time.

What, I can be running lathed wheels? No wonder!

 

[The Iceman]

Double check your drill job, are the rears canted 3 degrees? Are they drilled perfectly across from each other? Does the car balance 5/8" in front of the rear axle? Did you use pledge on the axles?