Suggestions on Tuning a car for The Giant Indiana State Museum Track

[Wombatchewed]

I'm building a car to run on the 125 foot Best-track at the Indiana State Museum next month. This Track has a huge drop from the the start into a long straight away to the finish. The Track record is 4.38 seconds and the cars move at incredible speed down the track. The stability of the car seems way more important when compared to running on a standard 42' track. I am considering moving the COG forward a little to add stability to the car. Also, I am thinking of putting 4 inches of steer over a 4 foot push to help hold the rail at high speeds. I am using DD4H Wood Fenders to protect the wheels and axles.

Does anybody have any building or tuning suggestions for running this monster?

 

[slingblade]

WOW... What are the rules... .?? That equates to 2x the average velocity of a 3.0 car on a 42' track (no consideration given to friction)

 

[Guest]

I have three going to that race and I have them set up with 4" over 4 and running about a 1/2 ounce of weight up on the DFW.

 

[5KidsRacing]

3 wheel railrunner with DD4H 92 PRO axles running his oil and prep process. Graphite won't win it... I would steer more than 4" in 4 ft., more like 5-6" in 4 ft. There are no axle rules that I see... Wheel rules are so conflicting.... cant touch them, but can remove mold seams and imperfections... crazy rules. If I remove the imperfections I would machine them every where... I mean what imperfection, they aren't balanced, that is an imperfection. Others at that race will be machining their wheels lightly I suspect to try and run well without raising any red flags. I would at the least true up the OD, remove the step and true up the inside edge.

Some of the past winners have ran larger fenders to try and protect their cars in that foam stop mat section.

 

[5KidsRacing]

Wait I have more!

I would put the rears 5/8" from the back of the car and stuff 2 ounces of tungsten behind.... put the rest in front of the rear axle.... whatever COG that works out to be is fine. Make the front fenders out of pine and epoxy them on very well. I would do something to increase the are where they attach so it is larger and they don't break off. You will probably end up with a 5" WB or a touch longer, make it as long as possible with still having tough front fenders.

 

[txchemist]

The aero is a big deal, so might spring for GEE fenders and put them on sturdy and it will help keep the alignment..

 

[slingblade]

LMAO at my new avatar !!! Thanks pinewood gods !! Mmhmmm!

 

[Wombatchewed]

The stop section was improved last year. They put a giant pillow inside a wooden box at the end of the stop section. However, they still stop pretty hard. Thanks for the advice 5 kids. I'll build it like you described. Still not sure on which wheels to use. Just to clarify, you would add more steer and put 10 cubes behind the rear axle. I was thinking of putting 5 cubes behind the rear axle and 4" of steer.

 

[Kinser Racing]

I'd build it with 10 cubes behind the rear axle and do more steer. At the higher speed your going to want a little more to hold you on the rail. /images/boards/smilies/thumb.gif

 

[5KidsRacing]

The stop section was improved last year. They put a giant pillow inside a wooden box at the end of the stop section. However, they still stop pretty hard. Thanks for the advice 5 kids. I'll build it like you described. Still not sure on which wheels to use. Just to clarify, you would add more steer and put 10 cubes behind the rear axle. I was thinking of putting 5 cubes behind the rear axle and 4" of steer.

I agree with Kinser....

I think most guys would think less steer because it is a long track and they don't want to scrub off more speed, but with the increased speed you want more steer to keep the car stable. I would go at least 6" in 4ft.....

The wheels? I don't really know... I would have to talk to someone that was there before and try and figure out what they look for at check-in. The rules are vague and misleading... You might want to email them and ask... I have heard they look at the wheels closely, but I don't know what they look for...

 

[Wombatchewed]

They use a notch cut out of a piece of metal. Your outer wheel diameter can't be smaller than the notch. I heard 1.70 will pass which makes sense if they allow "light sanding" to remove the imperfections. The wheel rules are not very specific and open to interpretation. I don't think they check the width.

 

[5KidsRacing]

I would order the Rage wheels and ask DD4H to cut to 1.170....