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TeamTerminator
05-10-2011, 09:43 PM
I understand that moving weight high in truck helps transfer weight. What is the effect of the weight left low on leftside frame rail compared to higher in the trunk area on left side? Right now i have a 56# chunk of lead on each of the frame rails . When track dries ive just moved rr chunk up about 15'' higher. Anyone have any knowledge of the effects of the weight mounted like this? thanks

Chaps
05-12-2011, 01:04 PM
If I get what your asking..........Think of it as a lever. The higher you mount the weight in the chassis the longer the lever= more leverage. So as the car rolls over with the weight mounted high you dynamically add more weight to the right side of the car. With the weight mounted lower the dynamic load will be less therefore closer to your static scaled weight. So what you are doing by adjusting the weight height is just adding more or less side bite to the car. There are many ways to do it but moving the weight is probably the cheapest and easiest mechanical method.

Graff Spee
05-13-2011, 12:11 AM
The higher the weight the more down force it will put on the right side. Due to the rolling over of the weight. The lower the weight the more it wants to slide or shear the contact parch. It all comes down to roll center height. Above = more down force Below = more shearing of cortact patch.

TeamTerminator
05-13-2011, 05:41 AM
Thanks for the replies guys!! Is that rule same for weight mounted on left side of car? Is there an effect if i keep the lead mounted on the frame rail or would mounting it high cause another reaction? Thanks

Chaps46
05-13-2011, 09:43 AM
Left side weight height is, in my opinion, less critical because it works against the roll of the chassis and is being lifted. You add static weight to the left tire (bite) and as the chassis rolls it evens the load to both rear tires evenly. At least that's idea.

FYI my car has a 100lb chunk mounted in the center of the chassis right in front of the fuel cell on top of the rear crossmember and two 45lb chucks mounted just below the decking over each frame rail about 10 inches above the crossmember. The car is a bit tight on a tacky track and usually turns pretty good once the track takes some rubber.