Limitless Diff fluid recommendations?

[dure16]

Limitless V1. Spool.

What weights do you recommend and why?

I searched and couldn’t find any type of consensus on F/R diff fluid weights for speed running.

 

[SrC]

If well Into the Triple digit speeds, 1 mil cst Fr and Rr may suit. Can start with 500k. But we all drive differently, and no 2 rigs are alike, so trial and error prevails.
Keep the Fr and Rr the same cst whatever you choose.
Raz Shifrin prefers very locked diffs. If not with fully locked out gears altogether.
My 3 cents.

 

[Dan B.]

Some of the more experienced speed runners believe that diff oil viscosity matters less here that in any other application, especially if running a spool. You’re not turning. Some do prefer locked diffs, as @SrC said, and some speed run cars double as street bashers as well. That’s where the proper fluid setup would really start to matter.

 

[SrC]

^^^ +1
That is why I always use the term "Dedicated" Speedrunner. We all drive differently. If you want to do both bashing and speed running then you really shouldn't go balls to the wall with Power and Diffs/drivetrain. There is a comfortable medium to do both. Drivetrain needs to be more forgiving if you bash/Drift.
Only My opinion. There are others.

 

[Dan B.]

^^^ +1
That is why I always use the term "Dedicated" Speedrunner. We all drive differently. If you want to do both bashing and speed running then you really shouldn't go balls to the wall with Power and Diffs/drivetrain. There is a comfortable medium to do both. Drivetrain needs to be more forgiving if you bash/Drift.
Only My opinion. There are others.

I agree. I changed direction on my last build midway through. It started as what would have been a dedicated speed runner, but then I got the full length SWB Scorched chassis for my next build, which will be for speed runs only. In the first build, after changing my mind and thinking it would be a street basher primarily with an occasional straight line speed run, I pulled the spool and put an Infraction center diff in it with a 40t spur and 1-mil fluid, and went 60k in the front and 30k in the back. I may end up tweaking that a bit after I drive it.

 

[SrC]

I could see how a thicker CST at the front benefits Drifting and bashing. Because a Long wheel base and narrow track width chassis tends to Push. For drifting that works against you. A thicker front diff will pull your drifts better. How I always observed it at least.
For "dedicated" Drifting, there are many other Variables and tweaks to consider as well. Spring rates, tires, Sway Bars, Rear Roll Center and so forth. And a Ligher rig overall will always drift better with less drive train damage FWIW.

 

[LibertyMKiii]

I leave my 1/7 diffs stock.
Always seems to drive best that way.

Ultimately you will have to test your car and see what you like best as this is always a topic of personal preference.

 

[SrC]

I currently and primarily run my V1 Lim with a 500k Center Diff, ( 46 Spur) 60k both front and rear. Geared for aprox. 87 MPH.
I run this setup mostly on a my 1/4 mile Velodrome oval banked bike track. Recently repaved. Racing my sons Infr.
The best setup for me and my sons V1 Infr. We all RC differently.

 

[Tirefryer426]

I want to say I'm running 500k front, 250k rear. I'm running 500k center, but I think I need to move up to 1m center.
I just recall in some of James' videos he felt that diffs worked better on crowned roads - so I figured I'd start with diffs and move to lockers if things just weren't working out.
So far - the diffs have been working fine. You do have to get the suspension dialed in. I think lockers give you a little wiggle on the suspension setup.

 

[SrC]

^^ +1
for a dedicated speed runner.
I find also that worn out Rear Hub BB's and sloppy Camber link ends and hubs contributes much to that rear wiggle. There is so much slop to dial out.
Lockers will only dramatize that slop for the worse.