b max4 factory vrs b max 4 III
 

Hi guys. I just bought a bmax 4 factory. I know its old by modern standards. I was hoping that some of the upgrades from the b max4 III would translate directly to the older car. Im mainly interested in the hard chassis, and the gear diffs. Can anybody comment as to just how much the older b max 4 can share with the newer 4 III?

Thanks!

Pretty much nothing. Front wishbones and that's it I think.

Dave

Thats rough. Im hoping its not the case!

the bmax 4-2 rear wishbones carry over to the III if you modify the roll bar mounting.

the chassis and drivetrain are all different. you can put the ball diffs from the 2 into the III, so maybe you can put the gear diffs into the 2?

If you want I can try if a III gear diff fits in a II. I didn't knew that the II balldiffs were compatible with the III. That's some good news. :D

Are you sure they fit Neal? I thiught the ball diffs for the III are all different part numbers??

I could be wrong. I usually am :)

no I'm not sure, i thought they were the same, you just need the plastic pinion, as the metal will wear out the plastic ball diff crown gear. i may be wrong of course! ive not actually tried them.

Afraid II ball diffs wont fit in III, ballraces are different

II uses 12x18 and III uses 10x15, otherwise they would of be a straight fit:cry:

ball races
 

If the diff assemblies just require different ball bearing size, then that should be no problem? I havent received the car yet, so dont know the arrangement. But, a 12x15 may make them compatible?

I also found that the gear boxes are different part numbers. However, again, if the 4III gear boxes will bolt onto the 4II or "factory" chassis, then perhaps the diffs will be correct?

Just grasping at straws here. Its rare to get a newer ish yok in the states,, and I would like to make the most of it!

III gear cases won't bolt on the II. Different chassis layout.

The diff outdrives of the III are also smaller diameter, which means the ball and pin on the end of the driveshaft of the II wont fit the outdrive. So you would have to use driveshafts from a III, but unsure if they are the same length as those in a II.

Personally it starts to become very expensive if you need diffs, bearings and driveshafts.

All righty then. I will have to wait till the car arrives and go from there. Once I have the manual in hand, then Accessing a pdf of the 4III manual and comparing side by side will reveal much.

run it as it is and enjoy it. besides a hex wheels conversion, there is little else that you can put on it from the III.

Got it! Plastic fantastic! Hex wheel conversion for sure. Such a nice high quality design. Im very impressed.