Hi,
I must warn you, customizing Mini-Zs is addictive and becomes quickly rather expensive
Anywayz...
Must-have :
- Carbon H-bar : tunable and much stronger
- Damper plate system : avoids vibrations, improves handling
- Front springs : tuning part
- Some small washers to lower the front end
- Tyres : I like GRP foams at the rear and PN racing slicks at the front (on a Kyosho-style track)
Good-to-have :
- Ball differential
- Steering knuckes with built-in camber
- Alloy motor mount
Not necessary :
- Center shock
- All the expensive and heavy aluminium bits
If you're looking for more HP, the Atomic Stock-R is quite amazing and works well with the stock ESC.
The ASF system (2.4GHz) has better electronics, specially at the steering : better centering, no glitches... Expensive though if you don't already own a Ko radio.
HTH