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Arrma Limitless 1/7 Drag Build Help Please ?

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  • 1 Post By Nineball

Arrma Limitless 1/7 Drag Build Help Please ?

Old 01-23-2023, 10:24 AM
  #1  
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Default Arrma Limitless 1/7 Drag Build Help Please ?

Hi

I have three Limitless.
I would like to build one of them to Drag.
And have the other for Speedruns and one for allround street bashing.

I have never build a DRAG Car before.
What do i need to do this ?
Important and good to know things ?

I run them all 8s.
In Drag you maybe want less Cells ?
Less weight ?
Foam wheels ? Or soft rubber slicks like GRP Rain ?
What tyre sauce you need if you use Foam at asphalt ? I have seen 4 different colors tyre sauce at my local shop. What is for asphalt outdoor use in drag ?
I dont need indoor carpet sauce

I have MAX 6 ESC, is that ok ? or do i need Castle ?
I know that Castle are great for speedruns. Drag maybe MAX 6 is enough ?

What motor would be good ? I have HW 4985 6s 1650kv and 4985 8S 1250kv Spektrum

Gearing ?

Spool at front diff ? Heavy oil rear ?
I have both Spool and also one Center diff 46t.
Center diff maybe should be 46t ? Spool or 2million oil in center ?

i have V1 Limitless

Im thinking top speed about 50mph is enough.
Need get there fast as possible without do anything insane.
Just random great Drag set up to have fun.

I have many 4s and 6s white china hobby line lipos with 8mm bullet connectors
i can do 4s. 6s. 8s with these
6200-9500mah

Please help me out with this.
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Old 01-23-2023, 05:50 PM
  #2  
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You can run like the RCDRL and RCHRA guys with foams, locked diffs, around 1:1 gearing, as many cells as you can fit, and a LOT of homemade tire prep... really not different from speed running. They still swap shocks for turnbuckles, run similar gearing, etc.

But that's an old formula that tops out around 1.6s for a 132ft pass. We're hitting that with 2wd cars on 2s now.

So if you want to do it right, combining the knowledge we've picked up on the no-prep side... get as high of KV as you can for whatever voltage you want, and make sure you get a sensored motor. When I was dream building a large scale drag car, it came down to something like the TP4070CM 2970KV for 6s, which is a decent power/weight ratio for the limitless. Gear it steep, like 11/36, and throw all the timing your esc will allow at it.

If it were me, I'd throw something like 25million in the front diff, 2mil in the center and rear. I'd also go with belted rubber tires and the same sauce we use for no-prep (because I know it the method. Also, drag racing is a lot harder on foams than speed running.). If you've got a fancy radio like the M17, set your throttle point so you can bury it and go. Otherwise, I hope your throttle control is good.
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Old 01-23-2023, 10:51 PM
  #3  
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Originally Posted by Nineball View Post
You can run like the RCDRL and RCHRA guys with foams, locked diffs, around 1:1 gearing, as many cells as you can fit, and a LOT of homemade tire prep... really not different from speed running. They still swap shocks for turnbuckles, run similar gearing, etc.

But that's an old formula that tops out around 1.6s for a 132ft pass. We're hitting that with 2wd cars on 2s now.

So if you want to do it right, combining the knowledge we've picked up on the no-prep side... get as high of KV as you can for whatever voltage you want, and make sure you get a sensored motor. When I was dream building a large scale drag car, it came down to something like the TP4070CM 2970KV for 6s, which is a decent power/weight ratio for the limitless. Gear it steep, like 11/36, and throw all the timing your esc will allow at it.

If it were me, I'd throw something like 25million in the front diff, 2mil in the center and rear. I'd also go with belted rubber tires and the same sauce we use for no-prep (because I know it the method. Also, drag racing is a lot harder on foams than speed running.). If you've got a fancy radio like the M17, set your throttle point so you can bury it and go. Otherwise, I hope your throttle control is good.
Nice Info dude
THX alot.

I will buy one TP4070CM 2970kv , have it 6s, that must be sick.
And Castle ESC.

The softest 17mm Belted rubber wheels are GRP Ultra Soft Slicks now. Will try them with sauce.

Fix the diffs, and play with gearing.
This will be fun

Drag GPS this is a must have 😂



THX again for help
Great
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