Track questions and more ! Expert replies needed

[sporty]

Greetings !

Sporty here 1st time ! (derbytalk reg)


Pro's,

How do you determine what is a ideal com ? especially when from a local pack to district the tracks vary.

My sons 2007 car, 1st in local, track record, 2.16. then 3rd at district.

However, recently tested, after lube and it was stored, on a 35 foot 1 lane track. 2.61,2.62 is about the best time it could achieve.

However, I worry that If I go to a more agressive com, at this local pack, that the car is going to flip up in the air !

this is either a 28 or 32 foot track.


So is this typical to balance this type of issue ? when facing different tracks.


If so, then how can some e-bay sellers and other who sell kits or pre-built cars, claim fastest car and so forth.

Without providing data of track and style. then should they also offer different cars for different tracks, if known buy thy buyer ?


So really a few questions here.


How can I build / test a car on one track and try and go forward with faster times, while testing on another track ? that is not the same !

Local packs here seem less inclined to allow test day on the track before the race !

You might get a 1 run the day of the race, but that would not allow any real testing or possibilities to ensure success.

Sporty

[DerbyDoc.com]

Hey sporty, I have 2 tracks. I have a wooden 32 ft 2 lane that I run 2.38's on with a "pure stock" car. and I have a 35 ft aluminum freedom track that I run 2.50's on with a pure stock car. I think that there are a lot of factors that come into play with tracks. Notice that there is a difference in WIRL and PWD's tracks. They both use the same exact track but they are about .07 seconds of difference. If I were you, I would focus mainly on alignment, more than COM. A well aligned car can make the difference between a 5th place car and a 1st place car. Tuning the alignment is the most hated part for me, but its well worth the effort. If your rules allow 1 gram wheels or at least wheels like the 1.8 gram inertia lites, then use them. Wheels will make a bigger difference over COM anyday. The weight placement is important, but its not as critical as some guys make it out to be. I keep my pure stockers with a COM of around 3/4 - 7/8 of an inch in front of the rear axles. Good luck with the race.
Heres a pic of my tracks.

[Parrot Racing]

Hey Sporty, thanks for the info on derbytalk, I am going to try it.
On pack tracks you have to be alot more careful on your com, I know on our pack track, which is wood, if I go less than about .85 in front of the rear axles, I am risking a wheelie. I had a car I raced at pwdracing and experimented with com at about .40 in front of rear axle, just to test the limits and it was off the track more than on.
If you don't get any test runs pre-race, then you have to play it safe. You have no chance of winning if your not on the track. If you get one practice run the first day, you can try and adjust the weighting with some stick on weights.

Hope this helps.

Enrico-Parrot Racing

[sporty]

thank you for the very good advise.

Yes alignment is something that I overlooked in the past. Or I should say how I checked it was much different.

Now We are on the right track, (lol) yes It can be tedious. I have just began to find this out.

And thanks for the track times, it helps also.

Sporty