Revo: RD Quickturn VS. Center Diff ?'s

[db302]

Howdy. Whats the big diff (pun intended) between the two? I'm sure I'm missing something here as my background is 2wd electric buggy. Could a few of you guys with a little more 4wd off road experience share some insight? Which way is best at LHR? Thanks. (Sorry if this has been asked before somewhere else...)

[db302]

No takers? My thinking is that the RD Quickturn makes the Revo have a one way bearing front end (like 1/8 4wd on road) while the center diff, well, I'm not quite sure what that does for it....

Hopin' to find out tho' - Later DaveB

[JOE]

the quick turn: pros- allows the front wheels to rotateindependantly during turns, IE no push during cornering alowing for fast and snappy turns on tight turns. cons-doesnt really do anything else but that.
center diff: pros- is always distributing more power the the front or back depending on which one has less traction(more) and more traction(less) this helps in many ways, even though you read this and think umm that doesnt make any sense i want traction for racing, well yes and no, there is a difference between forward bite and traction what you want is forward bite which is the relationship between how fast the tires are rotating forward and how fast the vehicle moves forward when the tires are rotated. by distributing the power like they do the center diff kinda balances the pwoer equation and allows for better forward bite with out worry of wheelys, and loss of control in the rough stuff, also during turns is less of a push becuase of what it does kinda ike a quick turn, and you can adjust the center diff by using fluid to get it to match your driving style. cons- on a revo you only have front brakes, but without a center diff it is actually front and rear but with a center diff its only front, so that why you hear about people trying to make rear brakes on the revo to work better with the center diff.

[squirrel]

+1 joey!

[JOE]

[db302]

Wow, I'm floored! Thanks, overyeoj, for taking time out of your busy and dangerous schedule to help clarify this. So let me know if you got me on the correct track...A center diff is more predictable and tuneable, especially on rough tracks. There is also a difference between traction (wheelies) and forward bite (vehicle acceleration) in which the center diff also excels. In braking, the center diff loses the rears (hence the people rigging custom rear brakes), while the RD Quickturn loses the fronts.

Am I up to speed now, or are there still things I'm missing? It sounds like at LHR I need the center diff to be competitive with a lot of horsepower.

Later - DaveB

[JOE]

ya thats all correct, my scedule isnt that dangerous right now lol im a MP desk Sergeant right now, but ive seen lots of people be really fast with the quick turns but i think a center diff is still better but its all in what you like and can afford.

[cowboy]

I'll be at leisure tommorow evening and will have a few diffs with me incase any one wants to check em out first hand.

[Tex]

Hey Cowboy, nice to see ya joined the forum... Are you going to be racing this weekend Saturday or Sunday?

[cowboy]

No I won't be racing. I'm in a chair and the handicap driver stand isn't high enough for me to see the whole track. I can get around the track but I wouldn't be competetive. Bernie says he's going to do what ever it takes so hopefully I can race in the near future.

[DAVEC-NITRO-RS4]

NOW, if you add a center diff to a Revo, do you race in MT or UMT? Truck with center diff= truggy......

[Tex]

I've met you a few times over the last 3 years. You used to race alot at RSJ and I raced with you at DirtDawgs lasts summer.

[Michowski]

center diff puts you in the umt, transmission puts you in standard mt. Thats the only way they seperate the 2 classes. Engine size means nothing.

[DAVEC-NITRO-RS4]

So it's gonna be an "Honors" thing with Revo center diffs, becuase they go inside the tranny case. DaveB how about posting a picture of you and your truck .

[Tex]

Dave it would be UMT....edit: wow too slow :wavey:

[db302]

DaveB how about posting a picture of you and your truck .

Will do, as soon as I get it put back together and get a decent body painted for it. Thanks to all for your input. Later - DaveB :joy:

[DAVEC-NITRO-RS4]

I was kidding you about the pictures...I just wanted to know when I was racing a "sleeper truggy" !!!!

[db302]

Ahhh. . .very wise of you. Actually, I'm probably going to post some pictures anyway, just to get some feedback on my first nitro effort LOL. - DaveB

[db302]

Got back earlier today from LHR (just checkin' out a race day) and wanted to know if my observations were correct... I really watched the monster truck class which is where I'll race. In the turns they seem to push pretty wide, but seem fairly predictable, where as UMT seem to have way more steeering in the turns. Is this because of thier center diffs, or is it driver skill? Remember I'm a N00b to Nitro, so I apologize if my questions seem mundane....

[rocco79]

its the center diffs .

[thenewguy821]

db, A lot of it has to do with the truck and set-up. The Maxx's, Savages, LST's, etc... in stock form, will have a little more push, because of the way they are designed. The Revo, with a little attention to setup can turn tighter. Part of this is due to the Shorter wheelbase. If you are still running stock setup in the diffs, swap out the diff oils. A good oil choice on the diffs, if you aren't running a quickturn, is 30k in the front, and 10k in the rear. The lighter oil in the rear, lets the truck turn tighter. you can also change the rear roll center, by putting the upper hingepins in the lower set of holes. This adds a little more traction up front, allowing better steering. I was surprised at how much extra steering those 2 little changes made.

[rocco79]

Newguy lighter oil in the rear doesnt help turn in bro.... If anything thicker oil will make the truck snap the rear around. Scott Cramer was explaining it to balt and me on saturday. he runs grease in his from diff. That allows the front to "diff out" and let the inside tire pull the truck threw the corner. In the rear he runs 10,000wt oil. I know its an mgt and not a revo but the principals are the same

[thenewguy821]

The way I heard it, was that the thicker oil in the front helps the front pull the truck through the turn, where the lighter oil in the rear allows the rear diff to break loose easier.

I'm not saying you or he is wrong, just saying what I've been told....

I know when I was running Buggy, I would run 3k in front, and 1k in the rear, and got the best steering that way.

[Michowski]

the lighter oil in the rear helps keep the rear end planted and push the truck through the turn were as heavier oil in the front diff helps pull the truck through. The front end will remain planted in the turns no matter what so thicker oil will benefit there but with the lighter oil in the rear when a tire does come off the ground more power is given to the wheel off the ground and that puts it back on the ground and there for pushes your truck through the turn.

[rocco79]

In response to new guy


Thats witha center diff though. I agree it goes against what is normally thought to be correct . thick oil in the front locks the tires together it doesnt allow the inside to spin faster they way it needs to to pull the truck around, Thats the push hes talkin about.

i know its sounds werid but the guy won the r/c pro north division