I am getting shoddy mileage on a 97 z28 with 113k miles. I tuned up just about everything i could think of except o2s. I got 2.73 gears and am only gettin 10-11mpg while not driving crazy. I got my maf screen still and have a 180 stat. New plugs and wires.

I pulled a few of my plugs and they all look like this: http://www.clanbbw.com/publicimg/data/images/large3.JPG
They have a whiteish gray at the tip. Is this a sign of anything? I changed them about 2k miles ago. I was thinking running a little lean. Do i need new o2s or are my injectors clogged or something?

Also, here is a pic of my old plugs next to a brand new ngk. The old one appears to be running a little rich.
http://www.clanbbw.com/publicimg/data/images/large2.JPG

Can anyone analyze the spark plug condition for me?

 

you're getting the same mileage as I do. i got a 97 z28 as well but before my torque converter i was getting around 16mpg city driving. i would also like to know ways to improve gas mileage.

 

Keep your FOOT out of it!!!!!

(joke)

 

Change your o2s and plugs use ac delcos, the ngk tr55 only last 15 18000 miles...

 

A cold air intake increases mpg. I've got a stock 97 Z28 ATM and im seeing 23mpg with me getting on the gas hard until i hit 60. I'm also seeing about 100-115 miles per quarter tank.

Dave

 

thats crazy....i have tons of bolt-ons, ported, polished, and decked heads, hotcam, and a tune and still get 26 mpg on the highway. Not nearly as good in the city but that's my fault.

 

I drive a 50/50 mix of aggressive acceleration and normal. I don't abuse my Z28 yet I do put my foot in in a lot. I get around 16 miles to the gallon too.

Interstate I get around 27

I drive a 1995 A4 with 3.23's and I keep my tires at 35 psi all around. (I average 240-250 miles per tank around town)

something doesn't sound right for your car to have that gas mileage, you can do a search on a lot of poles that have been conducted on this forum, yet that isn't exactly scientific.

just doesn't sound right, unless you are REALLY hard driving it.

 

I have a program that keeps track of my mileage on my pda, and i am getting 18.5 average. i do mostly city driving, and i treat it like its a Z28, without trying to race everyone out there..

By the way, this weekend is Header and Sparkplug weekend for me.. any suggestions on sparkplugs/headers? I was thinking about the Edelbrock 6894 set. any opinions are welcomed..