Ok,

i have an 02 350z. and the handbrake in it sucks.

i have adjusted the standard nissan shoe's, replaced them with project mu shoes, readjusted the shoes again. scuffed up the project mu shoes and the inside of the rotor. Adjusted the shoes again and adjusted the nut at the handbrake.
and its still crap.

on a gravel road it will lock up. but not on the normal road.

could it be the 275 kumho escta tyres?

Cheers

 

Its not the tires.

I've had 275 ecsta SPTs and MX's without ebrake issues. Its your ebrake tension adjustment.