Oil OK with 8-9 day wait after inspection?

[Billetspin]

I'll keep my first post ever here short. First, thanks! My kids did great last year with their cars because of all the info here (top 4).
Some info on our derby: wood track, 4 wheels must touch, oil OK to use (we used graphite however last year)

Two questions:
A) Our cars sit impounded for 8-9 days after inspection. Is oil still the best route with the car sitting that long?

B) In our adult division, I raced 8 heat races and then qualified for finals, so four more runs in the finals. In 4 of the heat races, I raced the eventual winner and I beat him every heat race. However when it came to the finals, he beat me all four runs (no changes to cars in between). Any ideas how that happened? My car slowed down a touch while his didn't. I didn't use any nail polish on body around axles (just sanded and graphite), so that may have been part of it. Or perhaps he was using oil (I used graphite).

Curious to know what you guys think, and thanks again!

 

[Mojo Racing]

You said oil okay to use, but you used graphite?

That is most likely the issue you ran into. Your car raced eight heats. This puts graphite to the end of its normal run time before needing to re-graphite. Oil holds up a lot longer generally and will be more consistent in your heat races.

More than likely, your opponent was on oil vs graphite on your car.

 

[GravityX]

To answer the questions in order: A) Yes. B) Ditto what Mojo said.

 

[Mojo Racing]

Oh yeah ! I forgot to answer the initial question... Right GX ! Oil will definitely last more than 8 days (if you are using Krytox or Rocket Fuel)

 

[Billetspin]

Thanks guys. I appreciate the quick responses. You guys rock. I have more questions, but these were the big ones.

 

[DerbyDad4Hire]

 

[Mojo Racing]

Thanks guys. I appreciate the quick responses. You guys rock. I have more questions, but these were the big ones.

Fire away !

You will find that most people are more than happy to help !

 

[Billetspin]

Fire away !

You will find that most people are more than happy to help !

OK...I guess the next question would be about weight. With a wedge design and the 4 wheel rule, would it be faster to move the weight to the bottom of the car? (I am assuming so).
We built three cars last year and all had similar designs, but different balance points (intentionally), but I had the weight on top. We want to make this year's cars with the balance point of the fastest from last year, but I thought moving the weights to the bottom might also help.

 

[Mojo Racing]

yep... lowering the center of gravity on your car helps your speed also... must of us run 1/4" plank cars with/without fenders... but even in my cars that I hand carve, I keep my weight to the bottom of the car.

you said different balance points... about how far in front of the rear axle does it balance?

 

[GravityX]

Mojo, I just read your tag line: I am not really surprised at how many times I shoot myself in the foot... What truly astonishes me is how fast I reload the gun !
Certainly a rib tickler.

 

[Mojo Racing]

Mojo, I just read your tag line: I am not really surprised at how many times I shoot myself in the foot... What truly astonishes me is how fast I reload the gun !
Certainly a rib tickler.

HAHAHAHA !

A line I learned from my former boss. LOL It has applied to me a time or two with this hobby.

 

[Billetspin]

We had one at 3/4", one at 1", and I think the other was 1-1/4" which was the slowest, but still took 5th. I have to look closer at the times between the other two (one was mine, so we did not race each other). Our track is not the best so there was definitely some lane discrepancy trends also.

I think between lowering the weight, going to oil, optimizing the balance point and nail polishing the hubs, we should be a fair amount quicker.

 

[Mojo Racing]

Yeah... wood tracks suck.

Okay... you just said nail polish the hubs... don't do that... if you are using nail polish because of rules, you need to put that onto the wood where the hubs would contact the body. 3-5 coats, sanded and polished.

For the cubs that I help that are stuck running on wood tracks, I generally set their cars up for 3/4" center of gravity (COG) to allow for a little more control. When they go to district, we are allowed to change the steer to something more aggressive and a little faster.

 

[Rat Pack Racing]

HAHAHAHA !

A line I learned from my former boss. LOL It has applied to me a time or two with this hobby.

At my age it happens so often I have trouble keeping up with the ammo!

 

[Billetspin]

Yeah... wood tracks suck.

Okay... you just said nail polish the hubs... don't do that... if you are using nail polish because of rules, you need to put that onto the wood where the hubs would contact the body. 3-5 coats, sanded and polished.

For the cubs that I help that are stuck running on wood tracks, I generally set their cars up for 3/4" center of gravity (COG) to allow for a little more control. When they go to district, we are allowed to change the steer to something more aggressive and a little faster.

That's what I meant on the nail polish...putting it where the wheel meets the body. No washers allowed, so I figured nail polish is next best option.

 

[Gravity Kingpin]

Yeah... wood tracks suck.

Okay... you just said nail polish the hubs... don't do that... if you are using nail polish because of rules, you need to put that onto the wood where the hubs would contact the body. 3-5 coats, sanded and polished.

For the cubs that I help that are stuck running on wood tracks, I generally set their cars up for 3/4" center of gravity (COG) to allow for a little more control. When they go to district, we are allowed to change the steer to something more aggressive and a little faster.

I got tired of the wood tracks all the cub scouting events use. So I bought a best track a couple years ago and have been changing there minds sense. I am now up to doing 6 different troops pinewood derby events. I would love to see all the wood tracks used as fire wood. LOL.

 

[Billetspin]

I've never run on anything else, but it is run pretty fair with heats on all lanes. No chance for testing though.