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Bugoff75
12-05-2006, 04:41 PM
Yes I've searched and no my question has not been answered already and I'm not a newb.

The stock diffs sucked from the start so I purchased a 3racing center diff and ST front and rears. great except the 3racing ball diff lasted only 2 minutes. removed it went to tighten it a bit and snapped the screw in half which sent all the little diff balls all over the place. lovely! so i went another route and JB welded the stock (stripped) center diff together.
now I was running a mamba 8K w/ 14t pinion and 8 cells, using a rubber washer as a slipper pad, front cvd's and one rear cvd (don't ask) alumn drive cups in the rear. that set-up was a slipper gear eater - went thru quite a few even the delrin gears. ran that set-up at the ECC and put the mamba25 into thermal shutdown during the A-main.
have since changed to a AON w/ 12t pinion and 8 cells. much better but was getting a clicking sound from the rear. fixed it by shimming. but the last test run i lost all power to the rear wheels. turns out the rear drive cup on the JB welded center diff was rounded off and spinning (from the 8k ECC A-main run) too messed up to fix so i replaced it with a stock center diff.
now for my question. the stock center diff unloads all the power to the front wheels. it did this before i even started modding this damn car and now that I'm back to using it its doing it again. A front 2wd car is what i drive to the track not what i drive at the track. how in gods name do i fix this? there is no binding every things smooth (upgraded the bearings) I'm out of ideas and getting pissed off.

Thanks for any and all suggestions.

morati
12-05-2006, 04:49 PM
Get an MIP center ball-diff and 3R blue delrin locked slipper.
Or you can do what a few of us here have already done and get a KM-RC chassis.
http://www.km-rc.com/oscommerce/catalog/index.php?cPath=34_22_27&osCsid=9739ee3c5971449e8d287b41053236b6

Bugoff75
12-05-2006, 10:45 PM
blue delrin solid one piece slipper gear is great for onroad where a slipper is not needed but i'm running in the dirt.
the KM-RC chassis looks great but the only time i've seen it run the center diff didn't hold up either. guy didn't even make it to the qualifiers in the ECC. broke it during practice.
I love MIP products but is it really any better then the 3racing ball diff? or the atomic? and why is my stock gear diff unloading to the front wheels?

morati
12-05-2006, 11:16 PM
blue delrin solid one piece slipper gear is great for onroad where a slipper is not needed but i'm running in the dirt.
the KM-RC chassis looks great but the only time i've seen it run the center diff didn't hold up either. guy didn't even make it to the qualifiers in the ECC. broke it during practice.
I love MIP products but is it really any better then the 3racing ball diff? or the atomic? and why is my stock gear diff unloading to the front wheels?Actually, the KM-RC chassis does not have a center diff, but a high quality slipper. Don't know how it could break but I guess anything is possible. I have found it to be quite durable. You can adjust the amount of slip you want to suit track conditions.
MIP is MUCH better than the 3R diffs.....My old 3R diff didn't last either. It wouldn't hold a setting and when I tried to tighten it, I stripped it as well. You won't have that problem with the MIP unit. You can also run the slipper just like you have it set up with the rubber washer or you can abrade the stock metal washer with a dremel and use it. Don't know why your stock gear diff is unloading to the front wheels but isn't that what they do? As you accelerate the rear tires bite while the fronts unload causing them to get most of the power. If you don't get MIP diffs all around, try going with ST diffs filled with Kyosho diff grease (5000wt front and 1000wt rear). Hope this helps......

Bugoff75
12-06-2006, 12:52 AM
already running the ST diffs. gonna have to pick up a MIP diff.

Bugoff75
12-06-2006, 10:20 PM
what about the new sealed metal MLST diffs? think they would fit?

Bugoff75
12-13-2006, 08:12 PM
Another kmrc chassis bites the dust. funny thing was two other guys seeing it went home and ordered one. went with a plain silver carbon fiber chassis myself and during switching chassis i solved my center diff problems. 1 little shim solved eveything. beautiful! runs great now with no chance of me stripping anything. well sunday will be the test - when it hits the track.