My advice on the nova revo cups.
 

My advice is to stay away from them as far as possible.

Three points of flaws in their design;

-they are too large in diameter and don't fit the stock housings.
-green line; too small, the rubber gasket doesn't fit, it doesn't want to stay in place
-red line; the flat spot is too small, it's tapered, so it's even smaller, rubber gasket will be pressed out on that point due to it

What you need to make them work; blue silicone loctite on both the cup and the screws to make them silicone-oil tight. and you also need aluminum diff-housings. I got 3-racing housings, which are large enough to mask their too large diameter error.

I am glad Mike is currently developing the 1/8th diffs.

I contacted nova about it, but they are too arrogant to talk with.

Thanks Serum i was thinking about them

Get the maximizers instead, they are from hardened steel.

they don't have got the three listed flaws, like the nova's.

Sorry Rene, I didn't know they were gonna be that bad off. I thought simply finding a housing big enough so they don't rub would've been it.

No worries Brian, it's nova's fault, not yours..

The key to success is silicone loctite. Apparently a must have in your pit-box..

I really hate "half baked" hop-ups. They are responsible for creating the phrase "no such thing as a bolt-on".

I've run into that with a few parts. VERY FRUSTRATING. I'm going thru it now with my Trans and chassis. The parts don't fit corrrectly. AAARG!

BTW, I'm not surprised that the "redline" area is how it is. They would have to broach the slot which would significantly increase the cost....even if it is the RIGHT way to do it.

They could have used a smaller bit as well, that would have made it bigger too. but with a smaller bit, the costs would go up as well.

In my opinion it's not about the problems, but it's the way they deal with it..
They refuse to admit their cup outer diameter is too large.. and all the other problems are waved goodbye.. 'hundreds of statisfied customers, you are the first, now get lost..' they offered my money back on the cups, but that doesn't solve their problem. And besides, mine are closed and shimmed now..

I am the one that is wrong. they reply my emails very poorly, only when i tickle them a bit i get a reply from them. That's the frustrating part.

I hear you Procharged. I know what frustrations to go thru if a 'bolt on' isn't a bolt on.. In my opinion they are not hobby enthusiasts, but they want to make money on us hobby enthusiasts.

That's a shame. I've run into a few companies like that. RC4WD comes to mind on the E-Maxx tranny gears. But we've discussed that.