Diff questions

[lincpimp]

Serum, thanks for the info. Where would I get gpm housings?

Are the flm hybrid bulks any good? Most of their stuff looks well made, and those are 60 each, and cover the diff cases and bulkheads in one shot. They appear to be cheaper than the other options I have seen, such as just the bulks for 40 bucks a pair.

I got mine in Hong Kong. I don't have the link on this PC, but when I get home I'll post it. I think its RCX - found it, these are the ones I used -

http://www.rcxshop.com/product_info.php?products_id=364

I've had decent service from them on several orders over several years. Be sure they have you zip code (that order took 9 weeks, lol!!)!!!

Have looked into upgrading brg size too as Serum mentions, but would need to buy some carbide tooling for my lathe to make that happen (ring gear is hardened) and so far at least for nitro, it hasn't proved to be a problem.


From HK, alum cases and and bulks are about $50 for each end. I don't have any experience with the flm pieces, but those may be just as good.

[Dafni]

Originally Posted by lincpimp

Are the flm hybrid bulks any good? Most of their stuff looks well made, and those are 60 each, and cover the diff cases and bulkheads in one shot. They appear to be cheaper than the other options I have seen, such as just the bulks for 40 bucks a pair.

They are good, but heavy. If you don't mind the extra weight, go for them.

[rhylsadar]

hi

there are different stages of upgrading savage diffs. practically most the savage diff problems were solved years ago.

one thing is to insert those little sliding blocks in the normal housings. by now some years later that hpi has done that on their own with the x ss you may just use their cups. however imo the old mod with the sliding blocks in high quality cups like maximizer is still tougher.

next step is the bigger bearings serum already mentioned. 8*16mm on the cup and on the 43t. if you stay with plastic cups you can use the kyosho IF103 that already has a steel output that uses a 8*16mm bearing. by now one can use the new hardened ringgear and pinion.

next step is adding two more bearings into the bulks that will take part of the load.

this all works well with plastic bulks etc. of course it can all be done with aluminum parts too.

i could show you pics of all those mods but sadly our private server is down since a few days. i guess i have linked those pics before in this forum.

but here is a old link that shows most of what i mentioned. its german but you may see some things in the pics.
http://www.nitro-mods-shop.com/SB/index2.htm

the problem with the gpm housings is that they are cut the wrong way. so you have to assemble the diff inside the housings if you are using the mod wiht the two additional bearings in the bulks. so using the normal plastic housings is easier with this mod.

regardless of what mods you do on the diffs the most important thing probably is a correct shimming. not to hard and not to loose.

and yeah of course the nightmare heavy tires you use do not help preventing diff damages.

bye
rhylsadar

[jhautz]

I am actually using what Serum sugested. I asked a similar question around a year ago and this was his sugestion then. HPI aluminum cups with the hard gears and the GPM dif case. I actually only put the GPM case in the rear. The rear was the only place I had any problems and sees most of the load on hard acceleration (the front wheels are usually off the ground lol) and I havent had any problems since going with the GPM solution. Its not quite the quality of the FLM stuff, but it sure is ceaper solved my problem.