studysession

Was hoping that people would post pics on how they have their steering setup on their drag cars. I see some use straight wire connected to servo and others use tie-rods. Trying to figure what is better and why?

Please post pics showing how your servo is mounted and how it is connected to steer your front end. Thanks

studysession

I have a GMS14 Electric Funny Car.
http://www.grandmotorsports.com/funnycar.asp

Here are pics of my steering. The chassis did not have enough area to put servo tape so I put a tiny piece of aluminum there and then used servo tape and electric tape to hold my servo in place. Then used tie-rods from my Mini-T to connect to.

Would appreciate it if others would post pics showing their steering. THANKS

PICS:

ahr43

Hi studysession,

New Era electric rail here-with highly modified front steering. HiTec HS-81MG micro servo lays on its side w/output shaft to right side. Servo attachment to chassis is with Radio Shack #64-2360 Superlock hook-and-loop Fasteners to custom cut aluminum pan which also holds the radio rcvr and mounts the antenna. Side rails on chassis also trap servo in place and prevent it's movement. There is a short drag link from servo arm to the left stg knuckle. Tie rod above chassis rails from left to right stg knuckle is Lunsford Ti turnbuckle with RPM ballcup ends attached to Ti ballstuds on each stg knuckle. We have found this method provides for both adequate toe-in adjustment and durability.

We can't speak to the wire method. Never used it. Sorry, no images we can post. Please don't use the image of the R2E in "My Models" as an example. That was during test phase and did not work well at all. The tie rod is still in place above the chassis. What we changed was the way the drag link came off the servo arm.

No sure by looking, but you may encounter some steering bind the way the ball ends attach to the servo arm. Best way to find out is to free roll the chassis with electrics switched "on" and with everthing is in place on the chassis like you will race it. Chassis should roll free and straight. Recommend doing a steering check at that time too. We have been able to identify and correct steering glitches that would have had a serious affect on high speed handling using the above method.

Hope this helps. Good luck.

//AC//

studysession

Thanks for the input. Do you by chance have a link to a pic somewhere showing an example?

NitroRage

Guys just remember when setting up RC Drag car steering,, Its a Drag car Not a Road Racer,,, Too many people put WAY too much steering in their cars then wonder why they Crash all the time... You only need enough steering to keep the car in the Lane your in on the Drag strip......Food for Thought..... John

studysession

Here's a pic of what I ended up doing. Haven't tried it out yet.

ahr43

Oh Yeah. Looking like an improvement over the first iteration. Track testing will tell for sure. Don't forget to roll-test it-full up weight and electrics on. Simple as it seems, that's important. Possibly, just maybe, the servo may be a little far back. But then, you shouldn't need any more than 'course correction' as steering input. Glad to see you're still taping it down. Don't need any errant steering input from a 'wandering' servo. Good job studysession. Lets us know how it works out for you.

BTW - what turn motor are you using? Are you using BEC off the ESC and racing battery, or do you have a seperate battery pack powering the rcvr/servo?

//AC//
Team AHR43

studysession

Thanks -
As for electronics, not sure yet.

ahr43

Wondering if this might have an RC drag racing steering application:

[link]http://www.hitecrcd.com/servos/show?name=HG-5000+Gyro+w%2F5083+digital+servo[/link]

E.T.s in Top Fuel Electric are tending toward the 1.4s and [possibly] 1.3s for 2008. I can't react quick enough to correct a car once it launches off the starting line. Watching the Extreme Class run, I don't think I'm the only one facing that challenge. [>:]

I know very little about RC aircraft systems, but I did get some gyro experience with analog missile guidance systems way back when with the US Air Force. Seems to me that controlling a car in "yaw" is what the gyro would sense and send input to the steering servo to correct the direction. This is digital, so there shouldn't be any of the gyro "hunting" that our analog guidance system experienced.

A primary concern of mine is that the driver maintain override control of the car. That is, steering input from the transmitter would overide the constant correction aspect of the gyro.

So, just wondering. Maybe some of you RC air/heli types could weigh in on this and see if its of value in pursuing. I thought I remember seeing a gyro related post on this part of the forum, but searched and couldn't find it.

AC