Forum: HoseHeads Sprint Car General Forum (go)
Moderators: dirtonly  /  dmantx  /  hosehead

I saw where another sprint car racer was DQ for being light at the scales. Can someone explain the logic to me? If the minimum weight requirement was 1400# for example, Why wouldn't you have the car weigh 1401# with a dry fuel tank?

The main reason is a gallon of methanol is 6.5 pounds and dirt surprisingly weighs a lot. Ideal goal to be competitive if say your motor game is a little on the low side and next cheapest thing is to have a lighter car. Some people take the risk and you get burned at the scales. 

Less weight equals more speed. For every pound over the limit, that is less speed. That is the reason you are going to have teams gambling on weight.

It looks like Gravel just gambled and lost.

Not Gravel’s fault. Crew chief is the one at fault.

Most teams check their numbers on a scale at the shop with no fuel in the car, a dry radiator and a set of canvassed tires. Methanol is equated at 7 lbs per gallon. Even with small tank 28 gallons at 7 lbs equals 196 pounds burned off during a race. Toss in 3 gallons of water in radiator is another 21 lbs (in case you lose water but keep running in big money shows).  Then you have brand new Hoosiers vs canvassed Hoosiers. The 2 rears alone lose 32 lbs between new and bald.  That's a total of 249 lbs you can potentially lose during a race.  You also have to take into account there was most likely any extra mud on the car for todays race.  Just some things to consider.

I saw an old Knoxville Nationals replay on youtube a while back where Schatz smoked everyone.  They showed him crossing the scales and if memory serves me correct he was like 160 pounds over.  I totally understand lightening up the rotating mass but I'm not sure weight makes as big of a difference when it's just on the car?  For instance on a dry slick track, could more weight be an advantage (not to the rotating mass)?

Tire wear can shave off 20 to 25 pounds of weight on a tire burning surface.

To be safe, I'd weigh the car with no fuel and no tires on the rear, just rims.   Maybe even a dry radiator.

That's an expensive 4 lbs and I doubt that their motor program is subpar.

     I see what your saying, but the crew chief knows about the 249 lbs. He also has a very good idea how much of the 249lbs. will be shed during the race. For the most part, it looks like it gets down to how many yellow flag laps they anticipate. From that aspect, why wouldn't you have the car weigh 1650 lbs.+ before the race starts?

i will agree with everything you said except "you will lose 32 lbs on the rear tires" Son they don't even weigh 32 pounds new. Whatever you are smoking send me some. But in your defense from someone that screws up typing all the time I hope you meant 3.2 lbs that may be a little closer to reality

+1

 
 
 
They don't even know how to spell sprint car 
much less chromoly...http://www.ycmco.com

I was going to mention the same example.  I remember this and someone explaining the advantages of the extra weight on a track that is slick-------kind of like a pulling tractor putting as much weight as possible at the back tires while still maintaining the balance.  

I'd be interested in knowing what all they do to cut weight to get close to the minimum weights.  I thought I had about every titanium and lightweight piece I could find on the last car I built and it was nowhere near the minimum.  Even if there was a fifth grader sized driver like all the lightweight WoO cars, it still would have been way heavy.  What would a new WoO roller cost to build?  Everything but the engine.  

.  

Little light weight driver with all the titanium money can buy and Gravel was right at old weight rule. To pass new weight rule, they bolted on 26 lbs. DQ'd at scales 4 lbs under after burning tires off of it. Wonder how much weight Rico has to bolt on...lol.

 
 
 
They don't even know how to spell sprint car 
much less chromoly...http://www.ycmco.com

They forgot to throw in the lead-filled towel on  the way to the scales.

The weight rule was made to equalize the field.I remember Cappys !st 1200 Nationals but it was car only.Just to use an example Sheldon is probably 100# lighter than Steve Kinser. I was told there were some cars below 1000# with titinium and carbon fiber parts which added to cost. It happens and it costs the teams and is the easiest rule to enforce.

With both rear tires bald you can lose approx 32 lb's of weight. Fairly sure a rr weighs 26lb.