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Old 02-24-2009, 07:57 AM   #7111
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Originally Posted by Jeremy Otis View Post
By the look of those front tires it looks like you have about 4 degrees of postive camber going on there.

By the way is this still the BMI websight? I just stated what Jason has been thinking.

Lets talk about batteries forward as apposed to being back and what this does to the handeling of the car and track conditions. Jason?
I've experienced a terrible push with the weight foreward ... which didnt make sence to me. Sort of figuted more traction, more steering . I guess the weight didnt want to rotate.
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Old 02-24-2009, 07:57 AM   #7112
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Originally Posted by Jeremy Otis View Post

Lets talk about batteries forward as apposed to being back and what this does to the handeling of the car and track conditions. Jason?
I don't know about BMI's but it should be the same as every other car. What I have found is that batteries forward makes the car more stable by taking away a bit of steering. It's great if the front end is hooking so hard that the car is trying to traction roll.

Batteries back gives a bit more steering and more responsive.
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Old 02-24-2009, 08:01 AM   #7113
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I've experienced a terrible push with the weight foreward ... which didnt make sence to me. Sort of figuted more traction, more steering . I guess the weight didnt want to rotate.
Yeah, it's counter intuitive but it's the same for nearly all racecars big or small. Basically when you move weight forward it will put more vertical load on the fronts (meaning more traction) but the traction doesn't go up quite as much as the weight will cause in increased side loading when cornering.

This is why wings are so great. You get the increased vertical load but add very little weight.
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Old 02-24-2009, 08:06 AM   #7114
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The majority of the time I run my batteries forward. I believe it helps with high bite situations and helps to mellow the car out a bit. This happens becuase you have less weight transfer from back to front. Running your batteries back will give you lots of weight transfer and almost makes your car snap through the corner. It gives you a ton of corner speed but does take away a bit of exit steering. You can compensate for this though with the right setup/tires. It can be little bit harder to drive smooth. Never try batteries back in modified. It is a disasterous...
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Old 02-24-2009, 08:33 AM   #7115
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Having the batteries forward will mellow the car out on corner entry and make it drive a little easier. However, you will have increased on power steering with the forward weight. With the batteries back, you will get more corner entry steering and a overall more aggressive car But you will lose some of your on power steering under accelleration. The key is to start back and creep the forward until the car feels comfortable to you. Some guys like a super aggressive car and some dont. It comes down to personal prefference and driving ability.
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Old 02-24-2009, 12:02 PM   #7116
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Jason you have PM. Thanks.
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Old 02-24-2009, 03:16 PM   #7117
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Doing my monthly rebuild on my DB12RR and learned something new. (isn't that the best part of this hobby? )
When using the #6 aluminum front end ride height spacers (3mm) on the front end, the front 8-32 screws supplied with the kit will come thru and press against the bottom side of the upper arm. Just use the trusty Dremel tool to shave 1 to 2mm off the screws then re install them.
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Old 02-24-2009, 03:19 PM   #7118
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Doing my monthly rebuild on my DB12RR and learned something new. (isn't that the best part of this hobby? )
When using the #6 aluminum front end ride height spacers (3mm) on the front end, the front 8-32 screws supplied with the kit will come thru and press against the bottom side of the upper arm. Just use the trusty Dremel tool to shave 1 to 2mm off the screws then re install them.
You are correct, you could leave it as is and adjust droop in the front. Totally kidding.

BTW, for reference, what is everyones cars weigh?? Mine that I posted on the previous page is 847g ready to race. Just wondering.
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Old 02-24-2009, 03:38 PM   #7119
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I had to add 21 grams to my car to make weight at the snow birds...can't recall what the actual weight was though.
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Old 02-24-2009, 11:45 PM   #7120
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Wow that's light, what batteries and motor are you using? I am at about 900g with mod brushless motor and 4600 mAh batteries.



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You are correct, you could leave it as is and adjust droop in the front. Totally kidding.

BTW, for reference, what is everyones cars weigh?? Mine that I posted on the previous page is 847g ready to race. Just wondering.
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Old 02-25-2009, 02:11 AM   #7121
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That was with 4600 EP cells and 17.5 and 10.5 motors. I also have pretty small electronics in the car.
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Old 02-25-2009, 03:25 AM   #7122
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Probably the ESC. I am running the Novak 4-cell GTB, 4.5L motor, spektrum micro receiver, and personal transponder.

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That was with 4600 EP cells and 17.5 and 10.5 motors. I also have pretty small electronics in the car.
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Old 02-25-2009, 06:48 AM   #7123
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can you use the springs from the IRS shock on the new Silva shock?
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Old 02-25-2009, 07:54 AM   #7124
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can you use the springs from the IRS shock on the new Silva shock?
Yes
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Old 02-25-2009, 08:23 AM   #7125
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Quote:
Originally Posted by Johnny Carey View Post
BTW, for reference, what is everyones cars weigh?? Mine that I posted on the previous page is 847g ready to race. Just wondering.
The last time I weighed mine it came in at 888g with novak 4-cell, 17.5, s9650, mini spectrum and cap, 4600's and pt. That was before I aded the brushless pod so I'm guessing its a bit heavier now.
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