Diff fluid calculation/mixing

[332_RC]

After buying a Infraction 6s, I've gone through all the diffs already & put what I believe is 50/200/20 in the diffs. The center was easy. Drained it, cleaned it, filled with 200k fluid I had on hand. Good thing I checked BTW, as the forum members here have stated, check your RTR diffs, they might be low or dry, & the center diff was nearly empty out of the box. The front & rear, I guessed at doing the calcs. 50k front & 20k rear, with 60k & 30k I already had. I removed some, not all of the 10k already in them & filled with what I thought would make those numbers. How do yall do it? 20k is available but not 50k. I found this here on the forum;
https://scriptasylum.com/rc_speed/oil_mixer.html
I used it. But I can't figure out any way to measure, just eye test. Anybody got any tricks? When I built my Notorious center, I did 50%/50% of 500k/200k thinking it would make 350k, it does not. 315k.

 

[Shadows]

I probably shouldn't post, as I'm not of any help you seem to be asking about. I mix, but don't bother reaching exact CST (weight) numbers. Out of curiosity, how do you plan to run this one? Parking lot hooning? Donuts and drifting? Or pure slalom, mechanical grip? I prefer my rigs to grip. I don't like the back of my rigs to break loose and slide.

 

[332_RC]

Parking lot hooning Donuts and drifting pure slalom, mechanical grip. I prefer my rigs to grip. I don't like the back of my rigs to break loose and slide.

I have a wide street in front of my house, rural. Street hooning-bashing. Donuts. Basic speed run here & there. I like the idea of grip, not breaking loose, but that takes away donuts & slides. Just a basic all around street basher.

 

[RCbuzz]

I don't do anything so precise that I measure out the mixes, just eyeball the level in the cup and mix and match.

I suppose if you run at the track it would probably make a bigger difference.

Nice little tool you found there.

 

[Shadows]

I have a wide street in front of my house, rural. Street hooning-bashing. Donuts. Basic speed run here & there. I like the idea of grip, not breaking loose, but that takes away donuts & slides. Just a basic all around street basher.

Different style from me, but I can dig that. I guess I would stick to the same overall balance it came with then, but I would go up on the viscosity (CST) on all the diffs for how you wanna run it. Maybe 100k - 50/50 mix between 500k & million - 60k

 

[332_RC]

The fluid is thick, really no way I see to measure it precisely & it doesn't need to be too technical for street bashing. Just thinking about it. I gotta do my Notorious center soon, it's been a while & I wanna get 375k in it. I also think it could go 50k in the rear, 60k front, with my terrain, the street & my backyard. If I have to start mixing diff fluid for these rigs, just looking for tips.

Different style from me, but I can dig that. I guess I would stick to the same overall balance it came with then, but I would go up on the viscosity (CST) on all the diffs for how you wanna run it. Maybe 100k - 50/50 mix between 500k & million - 60k

Sounds good. I don't have a idea where to start with it. The road isn't very grippy out there. My 3s Infraction spins out easy. What do you run with & what style? I've got 6s off road stuff, getting into on-road.

 

[332_RC]

I don't do anything so precise that I measure out the mixes, just eyeball the level in the cup and mix and match.

I suppose if you run at the track it would probably make a bigger difference.

Nice little tool you found there.

I found it on here. Yeah nice to mess around with it.

Calculator shows a 50/50 mix of 1mil & 500k is 700k not 750k. Cool little tool.

 

[sumguy75]

I usually have what I want on hand but when I don't I mix up what gets me close to what I have in mind. Nothing precise, I just eyeball it, thats close enough for me.

 

[Shadows]

The fluid is thick, really no way I see to measure it precisely & it doesn't need to be too technical for street bashing. Just thinking about it. I gotta do my Notorious center soon, it's been a while & I wanna get 375k in it. I also think it could go 50k in the rear, 60k front, with my terrain, the street & my backyard. If I have to start mixing diff fluid for these rigs, just looking for tips.


Sounds good. I don't have a idea where to start with it. The road isn't very grippy out there. My 3s Infraction spins out easy. What do you run with & what style? I've got 6s off road stuff, getting into on-road.

Crap, dude...I don't wanna steer you wrong. The infraction is a far cry from a 3s model. It's weight should help some over the 3s with traction, but if you're running area isn't very grippy like you say, I would (me personally) go even heavier at the front, like half 100k and 500k and thinner in the center...like no more than the 200k, with...50k rear. That would go a long way in preventing the rear end spinning out uncontrollably on slick pavement. That's more how I tune the diffs in all my rigs. Only, I go more extreme with 80 to 100k tops in the center. It works on my Kraton 6s with EXB LSD diffs crazy good. It's diffs are set to maximum limited slip 50/50 1 million and 500k in front, maximum LSD 100k center, and minimum LSD at 100k at the rear though. But it's HEAVY with all the M2C upgrades and runs 8s. It will NOT spin out at all. Handles like it's on rails with some expense on turning radius. I set my current Senton 6 build to 500k front, then center at 80k, and rear at 80k...but I have yet to run it. It's sitting in my hobby room with silver rear Felony Hoons on all four. I'm complicated I guess . But that's MY style.

That's why I suggested different for you.

 

[332_RC]

That's good info man! Senton sounds wild! Arrma has the white 53/100 on sale. I might grab a set.

 

[Shadows]

I run my Kraton in parking lots as well as gravel and grass. But all my rigs are primarily off-roaders. This is for an absolute street beast here. The speed runners all seem to go either a million F/R with locked centers, or just locked all the way around. But you're not going for that. That's why I first suggested the stock ratios but with higher viscosity. You need the major players with the street rigs here, because compared to them, I know jack . I'm just saying what I would go for in your spot. Makes me want an Infraction and tons of space to run one.

I can say this - ya' can't mess up too badly because you can always change it. It can be a P.I.T.A, but you can't do any damage with a bad diff tune. I have fun with it. Feels creative .

 

[slick2500]

You have to figure out how much fluid in weight fits in the diff. Then use the weight as a basis to divide by. X amount of fluid should weigh so much. Get one of those cheap scales they sell on Amazon. I have this one but haven't used it to mix fluids yet. https://www.amazon.com/Digital-Port...=1&sprefix=small+digital+scale,aps,128&sr=8-7

 

[332_RC]

I can say this - ya' can't mess up too badly because you can always change it. It can be a P.I.T.A, but you can't do any damage with a bad diff tune. I have fun with it. Feels creative .

For real. I've gotten better at changing the diffs out pretty good. It's not too bad. The Infraction you have to take off the extra wing/diffuser mount & the splitter hanger. Ima run it with the 50/200/20 & ruin a set of tires go from there. I like the sound of 100/200/50 tho.

You have to figure out how much fluid in weight fits in the diff. Then use the weight as a basis to divide by. X amount of fluid should weigh so much. Get one of those cheap scales they sell on Amazon. I have this one but haven't used it to mix fluids yet.

Ah. That makes sense. Could weigh it full of fluid & empty of fluid. Then add to calcs. If it's a 50/50 mix, it'd be half & half of the difference in weight.

 

[Shadows]

For real. I've gotten better at changing the diffs out pretty good. It's not too bad. The Infraction you have to take off the extra wing/diffuser mount & the splitter hanger. Ima run it with the 50/200/20 & ruin a set of tires go from there. I like the sound of 100/200/50 tho.


Ah. That makes sense. Could weigh it full of fluid & empty of fluid. Then add to calcs. If it's a 50/50 mix, it'd be half & half of the difference in weight.

Either of those sound sane and safe lol. It's a street animal, so it's gonna be fun out there no matter what. No worries. The main thing is that it's an infraction. Purpose built for that. One thing I found out with MYself, is that fussing negated (took away) some of the fun.

 

[Garcbomber]

Go heavier than that next time, you’ll have a more predictable experience. 100k/500k/100k or more since there is much higher grip coefficient, especially if the tires are sticky from heat.

I used to run a machine shop so jump on a manual bridgeport for government jobs btw