Solid mounts for the differential... how many are there?
 

so, by searching I can't quite figure out what Diff mounts to buy.

when I search for delrin differential mounts, I find only stuff like this:

http://www.mmr-direct.com/

and this:

http://cgi.ebay.com/ebaymotors/Rx7-R...item1c1e767a71

my question is... is that all I need?
isn't there another mounting point on the diff?
do I need to get solid subframe mounts as well?

I have delrin engine and tranny mounts already, but I have to replace the diff mounts too now because the diff shakes violently sometimes because it's mounts are so much softer than the rest of the mounts.

Yes, those are what u need.
The diff has 3 connection points 1 front difff mount (which is poorly designed and highly stressed) and 2 rear difff mounts which you are looking to replace.

You should install a pinion snubber and those mounts. If the snubber properly preloaded, the mazda comp front difff mount isn't a requirement, although it never hurts.

ah I see now. They just don't offer the front mount in delrin.

I just ordered the rear mounts and the pinion snubber from this thread:

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/how-pinion-snubber-install-867300/

no more clunking rear end! (hopefully)

You don't want a solid front mount! The mount needs to have some give, or it will rip off the mounting tabs on the sub frame.

Great, it well be like driving a while different car. Make sure u put enough preload on the snubber so that it is touching the diff while at rest.

No it does not need to give. If you run a solid front diff mount you MUST run solid subframe mounts. With both mounts solid, you won't rip the tab off the subframe.

^^ correct.
Sorry I've just seen too many broken tabs from solid mounts, that my knee jerk reaction is "no" lol