Speed run on grass

[Tron1000]

I hit 62 mph on a large relatively flat park field. I would love to hit 100 mph on grass, 🤣 My Typhon is really well planted on grass, even at 60. But I have a gut feeling that if I go any further, it will not end well. Any views?

[GMballistic]

Hitting 62 is a lot different to hitting a ton. You can do it though I'm sure and the Typhon is a good platform to use for speed runs, ...have you modified it at all? 

You'll have to change at least the ESC imho to break the ton as well as gears obviously. Tyre ballooning will also become an issue at those speeds. 
 

[Tron1000]

I put a hobbywing 4s ESC and a 22t pinion. I got 80 mph on the road with road tyres. If I use two 2s batteries rather than one 4s the car seems more quick.

[Stormbringer]

It maybe down to the C rating of the batteries giving you more punch 

[GMballistic]

11 hours ago, Tron1000 said:

I put a hobbywing 4s ESC and a 22t pinion. I got 80 mph on the road with road tyres. If I use two 2s batteries rather than one 4s the car seems more quick.

What are you using to test these speed readings please or is it more of a guesstimate?
Not that I don't believe you but I've been speed running a 6S Typhon since 2018 so have a lot of experience running mine. 

With the standard 6S BLX ESC, motor, spur gear and centre diff using a 23T pinion on road using a 6S battery I recorded first time out 65mph odd (withGRP tyres). Could of pushed it further like that but changed out my centre diff to a spool using a 38T spur gear and a 34T pinion gear which got me straight away a new PB at the time of 76mph. 

Kept that gearing/set up for a long time and just practiced my trigger pulls as well as trying different roads/distances to see how far I could get like that. Got me just shy of 100mph at 99mph as the ESC kept cutting. In the end I changed the ESC to a Castle Mamba Monster 2 which was what it needed to push passed 100mph. 

 

Have a read here of my build thread on the Arrma forum in case it helps you with your own Typhon: https://www.arrmaforum.com/threads/speed-runner-typhon-6s-uk-built-fast-not-bought-fast.10482/

 

It's a lot quicker than that nowadays though. 😉

 

Edited September 8, 2022 by GMballistic

[m4inbrain]

Could be a 3s running 4s. 

 

It 100% isn't a 6s, or it's 100% not hitting 60+ miles an hour. My Infraction 3s runs 73mph on 3s, bit of gearing and 4s (and lots of cooling and replacement electronics) would get it to 100mph easily. 

[Tron1000]

I am using a Skyrc speed meter.  I use two Voltz 2s  3200 mah batteries. The jump in speed from 3s to 4s is incredible. When I hit 80 mph on the road I guess I was using 90% throttle. I lowered the car practically to the ground. Got to say the car is pretty much planted. Tomorrow, weather permitting, I will video a speed run. Just got some new dboots road tyres.😎 In process of tidying up wiring.

Edited September 9, 2022 by Tron1000
Added photo.

[GMballistic]

@Tron1000good stuff, ...it's addictive chasing speed.  
Have a look at ROSSA on Facebook if you're enjoying the speed running game. Link: https://www.facebook.com/groups/1641915416068313

Any ideas what tyres you're going to try to use on grass? 
You can use fishing wire to help stop ballooning and if the tyres aren't belted then you could turn them inside out & use thick gaffa tape to try to make a basic belt inside the tyre yourself. 

[Tron1000]

I glue webbing material inside the tyres to stop them disintegrating.