Hey Yoshi, welcome to EM.
First suggestion:
-Get yourself an
MPGuino (mpg display, search the site, dcb sells em pre-built, all you have to do is wire it into the car. It's $55 and pays for itself quickly in improved driving habits.
-Second, change your driving style (easy while watching the
MPGuino). Avoiding stopping at red lights is an easy starter.... anticipate the red and brake early, coast to the red in gear, and roll up to the light as the green appears or traffic is moving. Takes far less gas to keep the car rolling than to get it rolling.
-The top 100 tips and 65 mods listed at the top of the page should get you going.
-If the Z is EFI, coasting in gear may cut out the fuel injectors=infinite mpg during decel. An MPGuino will tell you for sure whats happening.
Again, welcome.
PS: Real nice looking Z28 there, I've got a plain '84 fixer-upper