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giants17068
07-07-2010, 10:57 AM
Right now I have 56% left and need to get down to 54%. I can move the battery and fuel cell to the right or try and move the motor. What would be the best to try? Thanks Dan

leadorfollow
07-07-2010, 11:02 AM
I would start with battery. Do you have any ballast on the car that can be moved? if not then you're in the right direction with the fuel cell. where do you have the motor mounted at now? How much fuel is in the cell? Is the driver in the seat when scaling or not?

diplomunity
07-07-2010, 05:44 PM
wherever you settle on setting the fuel cell think about this do you want it to move towards or away from you desired percentages as the race goes on.

32 gallons weighs around 230 gallons. if your burning a lbs a lap at 50 laps your down to 180 lbs. where did your percentages go between the two?

just a though i always saw goes running their take over to the left to get that left % around 57/58 and i ran mine to the right. car didnt feel as good at first but as the night and adrenaline and the time to move came the right side cell always seemed to come in just right.

MasterSbilt_Racer
07-07-2010, 05:54 PM
wherever you settle on setting the fuel cell think about this do you want it to move towards or away from you desired percentages as the race goes on.

32 gallons weighs around 230 gallons. if your burning a lbs a lap at 50 laps your down to 180 lbs. where did your percentages go between the two?

just a though i always saw goes running their take over to the left to get that left % around 57/58 and i ran mine to the right. car didnt feel as good at first but as the night and adrenaline and the time to move came the right side cell always seemed to come in just right.

I agree with the spirit of your post. I like to have mine where the bite stays consistent.

JTSjet
07-07-2010, 09:15 PM
if you're scaling with 20 gallons of fuel you would likely have to move your cell to the right 3-5 inches depending on if you're running gas or alky and what your total weight is. cell dimension would affect that number too. just saying, i wouldn't be able to move mine that far. i'd go for the battery, it'll be close to 2%. also moving the fuel cell can dramatically affect handling. moving the battery can be compensated for with proper placement so to not affect handling.

Dirt2727
07-07-2010, 10:18 PM
Years ago , when messing with a bomber car, I welded the cross bars from frame rail to frame rail to mount the fuel cell on. Before I welded the front to rear bars in, I put the cell in with 10 gallons of fuel and moved the cell from side to side, I found very little differance in weight on each rear tire when i moved it.....best i came up with was , when i moved the cell all the way to the right or left, the length of the bars created leverage on the opposite side...now all that being said I know that where you put the cell makes a diff in handling but maybe its more because of relation to the roll center than actual placement side to side.....then again I could be just full of sh!t.

giants17068
07-08-2010, 06:15 AM
Those % are with 20 gallons of fuel and driver in the car. Driver weighs about 280 so I don't think moving the battery will be enough. Will moving the fuel cell to the right to much cause a pendulum at the rear through the turns?

Matt49
07-08-2010, 08:21 AM
Those % are with 20 gallons of fuel and driver in the car. Driver weighs about 280 so I don't think moving the battery will be enough. Will moving the fuel cell to the right to much cause a pendulum at the rear through the turns?

The "pendulum" effect is more of a factor of how far the object of mass is from it's pivot point or fulcrum which most assume to be the center of gravity of the car. Long story short moving the tank too far back would have more of an effect than moving it to the right when it comes to the "pendulum" effect that people talk about with cars.

Moving the cell to the right will tighten the car up but not entirely because your percentages are changing. You are moving an object that is ABOVE the rear roll center further to the right which will help the car roll and load the right rear.

JTSjet
07-08-2010, 09:32 AM
i was down this road before. i spent a lot of time moving the engine and the fuel cell around to hit static numbers only to find out it didn't make that much of a difference. my thinking was if i take this great big weight (cell/engine) and move it a little bit, it should show a big difference on the scale. it's actually the opposite because of the large area those items displace (think in terms of psi). if you still go this route, keep what Matt49 and others hit on in mind because you will be drastically changing handling of the car by moving that big of a mass even just a little.

Scott11JS
07-09-2010, 04:19 PM
put two 1inch wheel spacers on the left side and move the batt to the right and as far forward as your can i had 56% left side and i did these two things and it brought me right to 54% i also weight 330

Windy
07-11-2010, 02:41 AM
wheel offsets will make a good bit of difference..less work but more expensive....let us know what change you make and if it helps..thanks and best of luck..windy..

jedclampit
07-11-2010, 11:38 AM
If you move cell.....or any mass, if you don't reset/restore all your ride heights, your pissin' in the wind making comparisons.

56 left means your center of gravity is 6% to the left of center(simplified for example)...but... if you put it there what happens to fuel while cornering???

Where should it be to correct for dynamic weight transfer...you decide! ;)

Moving the engine right 1" should move you approx 1% on a typical late model.

You may want to look a your rear end location left to right for more , easily, but there are other factors effected. Move rear end to left to decrease left %.(this should show you why you have to reset ride heights,this is amplified by more angle in ph bar.)


What type of car is this?

Drop me a pm if you need help.(w/more info!)