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Old 04-24-2008, 09:37 PM
Fajita Dave Fajita Dave is offline
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Join Date: Aug 2006
Location: Virginia
Posts: 69
Hey Nerve,

This is a lot longer than I expected it to be :-p. Our cars are very basic but the details are what make them drive the way they do.

We are running stock 180 size motors and four AA Energizer 2500mah batteries. Our top speed is 12mph at the end of our 25ft straight away and it takes about 4.5 seconds to go from 0 to 10mph.

The chassis on the M18 and RS4 that we are racing are basically stock but on the M18 there was a whole lot of modifing to fit the open wheel body on it.

The M18s needed to be modified a lot of make the open-wheel body to fit. It moved the weight bias towards the rear a lot which helped it drive smoother. Even now my steering exp is at 70% to make the steering less sensitive. Even with that much exp it takes very tiny steering adjustments down the straight away otherwise you oversteer. There are a whole lot of changes done to the chassis but its about a page worth of explaining. Still its a stock chassis with a stock motor, AA batteries, and hard front foam tires.

The RS4 bottom chassis is completly stock but the upper chassis needed to be lowered a bit to fit the open-wheel body. The RS4 tracks straighter and the steering is less sensitive. We haven't figured out the entire reason for this yet but we have some ideas. The M18 has some slop in all 4 tires because of the indipendant suspension where are the RS4 has the straight axle bolted to the chassis. Less slop in the rear end means the car tracks straight better. The overall alignment makes a huge difference too (camber, and toe mostly). On the M18 we try to get the toe at 0 degrees front and rear.

The only things that really makes our cars drive smooth is tires that we are using along with the slick surface that we run on. We are running the XRay foam tires with the hard compound on the front and soft compound on the rear. The track surface is only wall paint applied with a paint roller so there is a whole lot less grip than the normal RC track surface. This forces the cars to push a lot which smooths out the steering and gives us a larger margin for error. Usually with the normal RC racing that has high grip surface and high grip tires along with crazy speeds for a small car makes things so fast its impossible to react or be accurate enough for the car to feel like its smooth to drive.

We have tried faster motors and bigger batteries in practice before and it just ruined the close racing. Pretty much anything faster on our track makes things to fast to react to. We are already doing 1 turn every second so there are only tenths of a second or less to react especially when you have 5 other cars you're racing wheel to wheel with on 22 inch lanes.

We have ran on concrete with about a 50ft straight away before which really made the steering faster because of the added grip. Still we kept the low HP setup because the cars were more drivable. Dispite the long straight away and pretty much double the space the racing was still more fun because the cars were slower than the average RC. Of course all of us have been racing with each other for a very long time so we are always racing close. These cars are only fun if your racing close on a track with tight turns. Otherwise they really are to slow and to easy to drive the have fun with.

Last edited by Fajita Dave; 04-24-2008 at 09:40 PM.
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