Ive got a 5.0 with 3.55 and M6 Trans. MPG through first 3 Tanks.
682 Miles City / 180 miles Highway = 862 Miles Total
20.0 MPG (260 / 13)
22.9 MPG (319 / 13.9)
21.9 MPG (283 / 12.9)

21.7 MPG Average - 79% City / 21% Highway.

I'm particularly impressed when you consider how much ragging on it Ive done to verify my high rpm clutch issue.

PS I only have two settings: Old Man (Low RPM Short-Shifter) and Race.

 

Gas sucking pig...

 

Nice numbers to start with. Flip that to 80% highway and 20% city and tell us what you are getting.

 

That's awesome! This I like to see. I will be almost the opposite.

Gene, how do you like the 3.55? I drove a Brembo/3.73 on wednesday and I just wanted someone's take on the 3.55 with the 6 speed. I haven't noticed any shortness of gear down low for the 3.31 or 3.73 really. Liked them both so I planned on the 3.55, that's why I ask!




I know, I talk too much.

 

That's exactly what I'm averaging ! Outstanding !

 

I havnt found anything not to like about them. I generally take off in 2nd. With the 2.43 2nd gear its more than low enough. Im sure they cost a mpg or two on the interstate but as you can see I dont do a lot of highway miles. I like being able to jump in 6th by 40 mph around town. Dont know if they will be any quicker than that 3.31 Car of Powerhouse's. 12.58 @ 112 Showroom Stock is pretty strong and I wouldnt be suprised if that car still has another 0.10 @ 1 mph left in it.

As to being low enough.... the 3.55 spins from a 20-30 mph roll in 1st. The only 2nd thought Ive had is if I should have taken the base 3.31 as Im not sure you gain a lot for the $395. I really think these cars will do a good job with any of the gears. The 3.73 might be nice if you Open Track as it will make 5th gear more usable (144 mph @ 6850 rpm with 255/40R19 Summer Rubber). However when i run at the drags in cool winter air I wont be bumping the limiter and it will pull a little stronger in the last 600' than the 3.31. I really think if I was street only I would have went 3.31.

PS I live at low altitude with my tracks at 160-570' ASL. If I was at higher altitude I would consider the 3.73.

 

I have just shy of 2500 Miles now, and I am getting on average about 21 MPG (5.0 Manual). The computer definitely is on the low side (about 1.5 MPG) which is unusal. They usually run high. My driving is 110 miles per day minimum and typically stop and go. Sometimes I am light on the throttle, sometimes I am heavy. You guys will definitely enjoy downshifting to 4th at 80 and stomping it. One thing I have noticed over the last few days, is how the exhaust is getting louder at low RPM's. I like it!!! Very baritone.

 

My Info Center has been showing about 1.4-1.6 mpg low as well. Mine definately has a big-block like tone but you cant really hear it below 2000 rpm. I hope mine gets louder at low rpm as well.

 

Y'all let us know when you do a mostly highway trip, I'll be interested in how the MPG runs then. Highway MPG is more important to me, too many variables in city MPG.

I just made a round trip to Dallas this past weekend in my SC '04 V6 and got 26 mpg, I know some better tuning on it will get me another 1-2 mpg, still not what I would expect from a V6 2011 but about what I would look for out of a 2011 5.0 car.

 

I"ve only got 250 miles on my GT w/ auto but it's been around 14.5 MPG.

I've only been doing little errands around town in stop and go traffic, so I don't really know how it will do on the highway. Took it out on the highway for less than 20 mins, so I'll find out how it does when I get to that point

I only drive 5 miles to and from work, so I don't really put too many miles on it during the week. The weekend is my time to drive.

I'm also hoping that the sound gets louder in the low RPMs over time. Just not loud enough.

 

ive been averaging 24 mpg in city/highway. i put it in 6th asap. 40mph in 6th. if i have to pull a hill i use 5th. get 23mpg city cruising. drops like a rock if i get into it.

 

On a side note, keep us posted on that clutch issue.

 

I'm reading way too much "old man" setting here. Those babies are gonna be loaded up with carbon before they get loosened up. Sounds like way too much time at 1500-2500rpm. Blow that biach out!
A well "broken in/loosened up/carbon free/drive it like you stole it" engine will give you a lifetime of good mileage later.

 

THIS.

 

Ohhhh... Its been "excercised". I just dont see a point in running 3000 rpm at 5% throttle.
My rpm and throttle usually match so to speak. The higher the throttle the higher the rpm.

 

78 mph on cruise control on highway, hit reset and getting 21mpg. Car has 250 miles on it. Manual.

 

You guys really have to get past the dash MPG readout, it's okay for using it to try and maximize your fuel economy but it is not an accurate gauge of the actual fuel economy for a tankfull of gas.

You really have to do it the old fashioned way, fill it up completely, drive it to near empty and re-fill it and check it against the miles driven.

 

Dude! This is the EXACT thing NOT to do! You need to fluctuate your RPMs, not set your cruise.

 

I think that was a quick test to see what it would show. Not a continous run.

 

If its like the others here thats actually more like 22.5 mpg (they seem to read about 1.5 mpg low) but my post was strictly the old fashioned way (miles divided by gallons) and a 3 tank average which eliminiates some of the variation.