Bad mpg with 2.73's???
 

I have a 98 Z28 and was wondering why I'm only getting 12mpg or maybe 13mpg, city driving? Is this normal when I got a tr224, vig3200, headers, ls6 intake, and 2.73's? I really need to know how to improve my mpg?

wow, that is horrible! did you ever have your car tuned after you got the stall put in?

My guess is the stall, mine only gets like 15 and it is mostly stock.

I did get it tuned, even though I still need a little bit of tuning, but would a stall lower my mpg that bad?

i have a 3400 stall untuned in my 99 w 3.23, cars never had spark plugs changed and im gettin about the same as you.

alot has to do w/ that right foot and of course the stall. lower gears and tuning will help in the city, of course the gears will hurt a lil on highway

I have had came to two theories 1. theory is that when I got my stall install that, I also put a big tranny cooler just under my air lid and obstructing air flow.
2. theory is that my car still had a bad alignment.
So would any of these cause bad gas milage and if they do how much?

I have a 3600 non lockup stall and I get like 17city, 26 highway... stock everything besides that, and I have 2.73's. But I drive like an old lady 99% of the time, so that really helps

I was wondering also If having your cut out open,will hurt gas milage

The big cam and the stall is probably what's causing it. I'm actually surprised it's not worse.

My girl is getting around 10 city mpg with just a cam, but its untuned. Before that she easily got 15-17. I'm guessing its not tuned or you have a clog somewhere. (air filter, fuel filter, etc)

I get around 16-17 in my car with a 3600 stall, 3.73's, stock internal.

mileage depends on a lot of things though. if you are taking short trips that will hurt the mileage. if you have a heavy foot that will hurt the mileage. 2.73's will hurt the mileage with a stall because the car will carry more rpm when accelerating in traffic as compared to a car with 3.73's in traffic. Cutout won't hurt mileage though.. alignment if the toe wayyyy off might hurt it. Trans cooler won't hurt mileage.

Other things that can hurt mileage.. dirty air filter, old/clogged fuel filter, low tire pressure...

A 224 cam is not a big cam at all :confused:

I have the same cam and a bigger stall (3600) with 3.23s. I get around 18 mpg in the city.

I really think he needs to have the car tuned by someone else.