Well my 13B's were not so bullet proof, I bought my Z when my 3rd engine went boom (ok I was used, and I was probably a mechanics fault). Although they are light I felt the Z could run circles around it stock (well 17 inch rims) and my RX-7 had swaybars, shock/spring combo. The Rx-7 did suffer from stock size tires however. The rotary engine does sing but N/A's not too fast. I liked it for the time but No way No how does it compare to the ZTT.