Promodeler DS630 v. Futaba A700 v. Futaba CB500 for a speed runner

[dk10438]

Working on my parts list for a new speed running build. I already have the promodeler which is essentially brand new. However, I have a Futaba 10Px, Futaba GPS, and plan on running telemetry (Castle and Futaba temp and maybe GPS) so I'm thinking about switching out the promodeler and changing to a futaba so I can program the servo AND run it via SBUS. I can get a decent deal on either the A700 or the CB500.

Is the A700 going to be too slow?
Is the CB500 too weak?
Or should I just save some money and go with the Promodeler. Please don't suggest any other servos. I either keep the promodeler or go Futaba for the programing capabilities and SBUS connectivity.

DS630
555 on/in
0.109 sec/60

A700
1027 oz/in (74 kg/ cm)
0.12 sec/60

CB500
354 oz/in (25 kg/cm )
0.06 sec/60

 

[Dan B.]

I’d stay with the ProModeler all day long, and the 630 is a great choice. You don’t want a super fast servo on a speed run car. When I “speed run” in my street Typhon I limit the response of my 630 via expo settings to slow it down a bit, and that’s only while running in the 70mph range. Futabas are also great (and ) but after a LOT of experience with the ProModelers I’ll probably never buy another brand.

 

[Diem Turner]

Speed isn't really of concern in a speed runner. I think there's even an argument to be made that slower is better. At speed you're making gradual steering adjustments. To me, speed is something you're looking for in a servo you plan on using for drifting or track racing where fast changes of direction are desirable.

As @Dan B. was saying, on speed passes you should be turning your steering response way down as it is. I have my D/R turned down to around 30%.

That all being said, I'd either go with the Promod or the A700.

 

[parcou]

DS630 but I've never used the other two so my vote may not matter much

 

[LibertyMKiii]

JX Servo CLS-HV7346MG 46kg​

Operating Speed (7.4V)	0.12sec/60°
Stall Torque (6V)	37.5 kg.cm

Stall Torque (7.4V)

46.9kg.cm

That's the specs on the one I have been running in 2 of my rigs. Zero issues and the prices is very reasonable

https://www.amazon.com/CLS-HV7346MG...mzn1.fos.18ed3cb5-28d5-4975-8bc7-93deae8f9840

 

[dk10438]

Maybe I was overthinking it but I’m running a gyro and thought that faster servo might mean faster corrections?

Ds 630 is a pretty nice servo and the only motivation for changing would be for Sbus compatibility which can clean up the wires a bit….

Thanks for the responses!

 

[Diem Turner]

Maybe I was overthinking it but I’m running a gyro and thought that faster servo might mean faster corrections?

Ds 630 is a pretty nice servo and the only motivation for changing would be for Sbus compatibility which can clean up the wires a bit….

Thanks for the responses!

You really don't want fast corrections. For speed running, you want that gyro turned waaaay down so you don't get death wobbles. Go with the DS630. You already have it, it's a great servo. I'd say the money you'd be spending on that A700 would be better spent elsewhere.

 

[Dan B.]

Maybe I was overthinking it but I’m running a gyro and thought that faster servo might mean faster corrections?

Ds 630 is a pretty nice servo and the only motivation for changing would be for Sbus compatibility which can clean up the wires a bit….

Thanks for the responses!

I get that, but tidy wiring is part of the fun in the build!

You really don't want fast corrections. For speed running, you want that gyro turned waaaay down so you don't get death wobbles. Go with the DS630. You already have it, it's a great servo. I'd say the money you'd be spending on that A700 would be better spent elsewhere.

I totally agree. The faster I go, the less gyro and servo speed I want and I haven’t even cracked 100 yet. My gyros are disabled now on anything that goes fast, and the servos are dialed way back.

 

[dk10438]

I guess in my mind I was envisioning a build where I would have an sbus hub that would connect
1. servo
2. gyro
3. futaba temp
4. castle tele
5. futaba gps
I think that would be pretty cool...

I get that, but tidy wiring is part of the fun in the build!

I totally agree. The faster I go, the less gyro and servo speed I want and I haven’t even cracked 100 yet. My gyros are disabled now on anything that goes fast, and the servos are dialed way back.

but the futaba servos will try to keep the car straight, not just correct turns...
I thought all the speed runners are using servos to keep the car tracking straight???

 

[Dan B.]

I guess in my mind I was envisioning a build where I would have an sbus hub that would connect
1. servo
2. gyro
3. futaba temp
4. castle tele
5. futaba gps
I think that would be pretty cool...

but the futaba servos will try to keep the car straight, not just correct turns...
I thought all the speed runners are using servos to keep the car tracking straight???

Raz said that he does use gyros, but he must have it turned down pretty freaking low. He also uses the Futabas and I’ve never used their gyros. I have a Futaba system on my Mojave but have never used the gyro. I don’t know about the esteemed Mr. McCoy. At the end of the day it’s your build, man! Follow your vision and learn as you progress. You’ll develop opinions pretty quickly the faster you go as you build up to higher speeds.

 

[Diem Turner]

Raz said that he does use gyros, but he must have it turned down pretty freaking low. He also uses the Futabas and I’ve never used their gyros. I have a Futaba system on my Mojave but have never used the gyro. I don’t know about the esteemed Mr. McCoy. At the end of the day it’s your build, man! Follow your vision and learn as you progress. You’ll develop opinions pretty quickly the faster you go as you build up to higher speeds.

I'm using the same gyro that Raz does. The Futaba GYC-441. It's super smooth. And yes, it's turned way down. You really shouldn't see the wheels move much at all as you move the car back and forth.

 

[dk10438]

have the gyc441 in my limitless and I have it set at 17-20