Update: I went to replace the zx center clutch and found that none of my main shaft assemblies would fit and work. HMMM so Apart comes the entire la33 assembly. It turns out I had 2 of the pully shoulders stuffed into the rear drive section, causing a mis alignment, melted plastic, and in consistent center diff action. So, back together it goes, correctly this time. Other changes. Smaller diameter wheels (2.0) and smaller tires imex road dogs, 17t pinion, slightly loosen rear diff, fine tune camber and sag for street running, add a schotky to the motor for better brakes,,, and WALA! Works much better now. Im still not sold on the merits of the center diff, but at least I have a solid platform to tune with now.
The center diff adjustment has held, and the slippy slidey tires seem to keep the front and rear a bit better balanced. Im hoping to switch to turn buckles and zx5 ball cups and studs on the camber links. That, and a body,, and I think we have another long term runner!
Going to try and scrounge up an 18t pinion in .04 module (metric 40 pitch?) also. Ive also got another la33 assembly completed with the hyper clutch, and it will likely go into more of a zxr based buggy tired set up.