Limitless Diff fluids for speedrun!!!!

[LibertyMKiii]

Most of us over time found that fully locked is not good.
Notice how Raz stopped using the scortched lockers in his builds?

Most prefer thicker front than rear. I suggest trying 500k front 100k rear and see how that goes.

1/7 scale is generally less sensitive on this but a 1/8 like a Typhon does better with a setup like 500/100

 

[Mr.Duke]

As long as you run a spool in the center, keep the front and rear to stock 10k.
There’s no advantage to running thicker or locked front or rear diffs.

 

[LibertyMKiii]

As you can see with they varied answers to this question it comes down to a personal preference.
on a small 1/10 scale car it absolutely benefitted from thicker front diff fluid. 1/7 scale I always leave stock fluids alone and works fine.

 

[ARRMA-GET’M]

Hey guys, I’ll add my 2¢….. yes locked diff vs not locked does make a huge difference! On top end speeds?, no… handling yes. The BEST way to determine AND test what diff weight is best for (you) and the road (you) drive on is like this., #1 diffs only work during hard acceleration and turning/drifting., but bcs this is an rc car, hard stopping also effects diff action. Because we are focusing on speed runs ONLY well look at hard acceleration and stopping, yes stopping so you stop in a straight line bcs we don’t have disc brakes to control each wheel individually so it can diff out on a stop. #2 let’s pretend that we have a locked diff in the front and rear to eliminate the guess of “how thick” of oil.. now think to yourself hmmm, why and when do I need diff action and how much diff action do I need it any? Here’s another question, “when do I need/want NO diff action”? A 100% locked diff is great for a hard take off and continued hard acceleration, but it’s ONLY good for just that. Once the rc vehicle is in motion, having a fully locked diff can get you into trouble. If the rc car just happens to catch cross winds and gets nudged off course, the rc vehicle will take that alternate rout like it’s on rails. A vehicle with diff action responds to changes in direction gracefully when at high speeds. A vehicle with NO diff action will take all and any course like it’s on rails even if it’s not a desirable path. So yea you do want diff action. More diff action is always better than NO diff action, it’s just that we want both benefits of that “buffer” at high speeds and to take off like a roller coaster. My BEST advise to everyone is.., the better condition and cleaner the road is, the heavier diff oil you can go because it’s “safe” to do so. You’ll always want your front more heavy than rear. I’d say front should be twice as thick as rear. This will allow you to have diff action at the rear but the front will pull in a straighter line while acceleration. You could also lock the rear with silicone plugs to start with and add ONE drop of bearing oil at a time in the diff case through that grub screw hole. Just one drop will loosen the diff and you can control how much diff action you want to allow without having to rebuild the entire diff again. Just remove the diff case, and access the grub screw from right there. Hope this was good info

 

[LicketySplit]

As long as you run a spool in the center, keep the front and rear to stock 10k.
There’s no advantage to running thicker or locked front or rear diffs.

Late to this thread but it’s relevant. I’m gonna have to agree with this. I started off on stock. All my runs were straight and easy. Went to 80k. Not bad but I noticed it became a little more squirrelly. Last night I went 500k/200k. Ran it today and yea, nah. Even the slightest correction made the rear want to kick out. Horrible. I put 10k back in when I got home so hopefully tomorrow I’ll get out for another test.

 

[ARRMA-GET’M]

Late to this thread but it’s relevant. I’m gonna have to agree with this. I started off on stock. All my runs were straight and easy. Went to 80k. Not bad but I noticed it became a little more squirrelly. Last night I went 500k/200k. Ran it today and yea, nah. Even the slightest correction made the rear want to kick out. Horrible. I put 10k back in when I got home so hopefully tomorrow I’ll get out for another test.

Agreed…, I went locked at the rear and it was awful. I replaced the silicone with 20k diff fluid and it’s a lot better, I even suggested to myself 15k would be prime. 10k is stock but maybe it didn’t have enough or was just degraded or low quality.

 

[fish]

Most of us over time found that fully locked is not good.
Notice how Raz stopped using the scortched lockers in his builds?

Most prefer thicker front than rear. I suggest trying 500k front 100k rear and see how that goes.

1/7 scale is generally less sensitive on this but a 1/8 like a Typhon does better with a setup like 500/100

I took this advise from you guys. For running Stretched Kraton 6S fast across all surfaces, Grass fields mostly.
500f/ 1000c/ 200r and it made a huge difference keeping the car straight and planted.

I was at 80f/ 100c/ 60r and there was always 1 or 2 tires ballooning more than the others (more so the front) and there was always allot of lift in the front. I I would also see the car shifting direction, you can notice the AVC doing its thing.
I notice this mostly with the larger MT tires and assume the forces are the same with a Hoons or buggy tire.

Afterwards/now the nose is more easily planted and the tire ballooning is much more even, and seemingly lesser so.
Speed went Up by 6-10 mph too, which I wasnt expecting but im not surprised.
I can now run AVC lower too.

I also noticed that the backend will come around more easily on turns. Which I like, makes turn-arounds quick and fun ;-)
Learning allot!



added/edit:
I have a Stretched Typhon 6S for pavement and dirt mostly and I left the Diffs at 100f OD /200c LSD/ 60r OD and its good as is, not looking to change it. Also from many recommendations from you Lunatics. Only had it up to mid 70's so far. Pinions and tires for 100 coming soon.

If it ever stops Raining!