Well, I owned a t-maxx 3 years ago or so and I always had clutch slipping issues. Especially once I went big block. Constantly frying shoes, breaking springs, overheating the bell and ruining bearings... It just got old. Then I bought a savage, installed a 3-shoe and ran it for over 10 gallons without doing anything to the clutch other than replacing a set of bearings. I also would sand the gloss off the shoes every gallon or so.
Then I got a revo... back to the crappy traxxas clutch again. I've only run about 1.5 gallons through it total. 1/2 gallon with the 2.5R, about a gallon with my os 18. Busted the spring last weekend, which in turn marred the bell and messed up the shoes. Yay...
I noticed someone had posted on another forum about using a 1/8 clutch. So, since I had an extra 3 shoe savage clutch and a 15T bell laying around, I figured I'd give it a shot.
I only had to move the trans about 3mm-4mm forward. I drilled a set of holes in front of each trans bolt, dremelled into a smooth slot to the old hole, dremelled about a quarter inch off the chassis by the brakes so it could slide forward, drilled/tapped a couple new holes in the trans case flange to keep the trans from sliding backward (extra insurance) and re-did my brake linkage. On the engine, I just had to make a shoulder bolt out of a 3mm bolt and nut to gain the extra 1/8 inch needed for the CB to ride on.
Now I have a 1/8 scale clutch on it. I also now know how much power the TM really has!
However, the TM apparently idles a bit higher than a BB, so the clutch engages way too early. I drilled a hole in each shoe tonight to lighten the shoes a bit so it will engage later. I'm just hoping I didn't get too aggressive.
Sorry for prattling on... Here are some pics:
This is without moving the trans just to see how far I had to move it:
I also had to grind a bit off the throttle servo box:
You can see my extra bolts near the center of the trans:
A photo from the top so you can see how much I had to move it from a different angle:
And, the holes I drilled in the shoes:
I do know from today that it's faster on the top end, which means the old clutch slipped when in second gear. I geared down a little bit from 36/15 to 38/15 to try and keep the top speed a bit closer to my liking.
BTW, I need to remove more material from the shoes, it still engages too early for my taste. It's better than it was, but still really low in the RPM's.
This is on a 2.5 chassis revo with a OS 18TM.
These are the extra parts I used:
OFNA Bell,
Savage flywheel/Shoes
The t-maxx and other 1/10 nitro's have different gear pitch than buggies and 1/8 scale. The revo has the same pitch as buggies and 1/8 scale.