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thzero · 12.09.2010, 02:38 PM

Next phase is implementing a center diff. Doing this for a couple of reasons; a) to mount the 1520 motor, b) better turning, c) remove the tranny, d) because I want to! Granted I can grind out the chassis to allow the 1520 motor to fit, but really with the TVPs its a PITA to work on.

Replacing the Savage tranny with a center diff means you lose the gear reduction of the tranny. So now you need to run large spurs (50, 52, 54) with small pinions (8, 9, 10, 11).

I have all the spurs, as I was planning to use a RC8T center diff [because I have an RC8T], but smallest mod 1 pinions I've found is a 9. But really these are getting small and bit worried about them holding up frankly.

So my next option was to explore using different front/rear diffs. Someone once mentioned to me that the Lightning Stadium Pro diffs should fit. So I went and look up part numbers, but also ended up checking out some other HP and Hot Body vehicles. And dang the HP Vorza and HB Lightning Pro diff internals looked much the same, both being spiral cut too, and you could use center dogbones to boot. So I ordered some, and low and behold the 43 tooth ring gear fits on a Savage diff using the Flux/XL diff cups. And it fits into the bulkhead needing only minor shimming. The 10t spiral cut bevel gear fit, but has a bit of play (About an 1/8th of an inch or so) that needs to get taken care of. But nothing insurmountable at all. The 43t ring is much thicker than even the bulletproof diff, so with a good shim I don't see any issues using these in the Savage under 6S. Especially considering they are used in the Vorza and I run spiral cut diffs in my RC8T and haven't had issues.

So now with using the 4.3:1 ratio front/rear diffs I can run one of the smaller center diff spurs (50) and play with 12-15 tooth pinions.

I'll post some pics tonight with everything mocked up.

	(#210)
thzero RC-Monster Aluminum Offline Posts: 800 Join Date: Oct 2009	12.09.2010, 02:38 PM Next phase is implementing a center diff. Doing this for a couple of reasons; a) to mount the 1520 motor, b) better turning, c) remove the tranny, d) because I want to! Granted I can grind out the chassis to allow the 1520 motor to fit, but really with the TVPs its a PITA to work on. Replacing the Savage tranny with a center diff means you lose the gear reduction of the tranny. So now you need to run large spurs (50, 52, 54) with small pinions (8, 9, 10, 11). I have all the spurs, as I was planning to use a RC8T center diff [because I have an RC8T], but smallest mod 1 pinions I've found is a 9. But really these are getting small and bit worried about them holding up frankly. So my next option was to explore using different front/rear diffs. Someone once mentioned to me that the Lightning Stadium Pro diffs should fit. So I went and look up part numbers, but also ended up checking out some other HP and Hot Body vehicles. And dang the HP Vorza and HB Lightning Pro diff internals looked much the same, both being spiral cut too, and you could use center dogbones to boot. So I ordered some, and low and behold the 43 tooth ring gear fits on a Savage diff using the Flux/XL diff cups. And it fits into the bulkhead needing only minor shimming. The 10t spiral cut bevel gear fit, but has a bit of play (About an 1/8th of an inch or so) that needs to get taken care of. But nothing insurmountable at all. The 43t ring is much thicker than even the bulletproof diff, so with a good shim I don't see any issues using these in the Savage under 6S. Especially considering they are used in the Vorza and I run spiral cut diffs in my RC8T and haven't had issues. So now with using the 4.3:1 ratio front/rear diffs I can run one of the smaller center diff spurs (50) and play with 12-15 tooth pinions. I'll post some pics tonight with everything mocked up.