Vendetta

Okay, I'm starting to get skeptical. Since the tune I've been getting increasingly better gas mileage... last time I filled up, I could have gottena round 300 miles to the tank. Assuming I've read correctly and the tank is 15.5 gallons, that about 19 miles per gallon. Wtf?? Damn good gas mileage!!

This week, I've got just over 200 miles to the tank, and the needle is at the halfway mark. Wtf?? Is my gauge off or something? There's no way I can be getting this good of gas mileage... right? 400 miles to the tank would be like 22mpg, and this is one a supercharged setup!

OneMeanZ

iTrader: (2)

Yea that's good gas mileage! On a full tank I only go 190 to 200 miles before I have to fill back up...and that's on a stock car.

dhdenney

iTrader: (53)

I used to get 20-22 in my M6 before the tear down. Then I had shorty headers with a Flowmaster muffler (no cat) and a MSD Digital 6. I did a lot of highway miles. The fuel gauges on the Fbodies are off. I would hit 200 miles at the 3/4 full mark and then after that it seemed like water going out of a bathtub. After the half mark, look to fill up soon.

TSAEB

iTrader: (5)

yeah my guages are for sure off....are faulty guages a common prob with lt1 camaros

Vendetta

Well my speedo gauge is definitely off, I have no idea what caused it, but after I finished the injector swap and PCM tune it happened...

Transamula

My speedo is off by 12 mph too slow, which is very fun arond town... and my gas gauge buries it, but once it hits the actual guage at about 140 miles, it plummets pretty quick. On my LOOOONG *** road trip to Long Island recently I got 27 to the gallon all highway. No bullshit! I was pretty impressed! More impressive was after the 4 1/2 hours of driving she was still up to smoking a stang on the home stretch

dhdenney

iTrader: (53)

That 27 mpg wouldn't be accurate if your speedo was off. If you aren't logging correct miles, then you can't accurately calculate your fuel mileage. If you're going 72 mph and the speedo says 60, then in one hour your odo will have logged 60 miles whereas you went 72. In reality you would have gotten better than 27 mpg. No being a dick, just some food for thought.

OneMeanZ

iTrader: (2)

Is there anyway to fix the fuel gauge? Because once I hit a quarter tank, I better go fill up because it goes everywhere after that, up, down, up again, then down again.

Transamula

I thought that the odo went by something other than the speedo? I stand corrected. Very Interesting, but my math was correct...Maybe my car is actually a 3.4.....

Gangly

the gas gauge isnt broken or malfunctioning. every gas gauge of every lt1 does the same thing...
you get crazy *** good gas milage for the first quarter tank then the needle starts to plummet after that. Its just the way it is. if you got 200 miles at the halfway mark...look to get about 75-100 for the second half.

dhdenney

iTrader: (53)

Yeah, I've never known an Fbody to have a really accurate fuel gauge. I had a 94 Camaro with the 3.4 V6 before my T/A and it was pretty much the same way. I don't think there is an accurate one out there! But the odometer is driven by the speedo. It makes sense though, if your speedo doesn't work, then it will be sitting on zero so your odometer isn't working because as far as the speedo goes, it isn't going anywhere. I have a buddy that hasn't logged a single mile on his since his speedo has been out.

Vendetta

Wait, does this mean if you found a car with a broken speedo it's whole liftime that had 50k on the clock, it would in reality have a lot more miles than the odometer indicates? That's pretty useful if you wanna rip somebody off.

TSAEB

iTrader: (5)

pretty sure that has been done...

87GMC

The Z M6 get damm good mpg. My bone stock 98M6 got a little over 30mpg on the highway. I love the M6

dhdenney

iTrader: (53)

Yeah I know guys that have probably driven over 20,000 undocumented miles because of a broken speedo.