My Gas Milage
01-30-2010, 12:54 PM
#1
New Member
Thread Starter
Join Date: 10-04-2009
Location: Kentucky
Posts: 12
My Gas Milage
I drove my HHR from Kissimmee Florida to Kentucky one day and back the next. The best I saw on the gas milage readout was 28.5 MPG. I would have thought a 3100 pound econo car would do better than that.
I have a 1999 corvette and it will do that good.
I have a 1999 corvette and it will do that good.
01-30-2010, 05:10 PM
#2
Senior Member
Join Date: 06-09-2009
Location: Clinton, Mass
Posts: 2,950
How many miles do you have on it?
I averaged about 28.5 for the first few thousand miles.
It eventually crept up to about 32 in the summer.
The best I averaged on an extended trip (about 525 miles) was 33.5 from Virginia to Wilkes-Barre, Pa.
I averaged about 28.5 for the first few thousand miles.
It eventually crept up to about 32 in the summer.
The best I averaged on an extended trip (about 525 miles) was 33.5 from Virginia to Wilkes-Barre, Pa.
02-01-2010, 03:46 AM
#5
Senior Member
Join Date: 09-11-2007
Location: Palm Bay, Florida
Posts: 1,378
Do the calculations for mpg. The DIC guage in my HHR runs low. Usually on the highway, using cruise control and driving the speed limit, I'll get 32 mpg or better. Any around town driving kills mpg if you have a heavy foot.
02-05-2010, 06:01 PM
#6
Senior Member
Join Date: 07-10-2008
Location: Not necessarily Humbolt County
Posts: 421
I know there are various thoughts on the DIC accuracy when it comes to instantaneous and average MPG but it's actually pretty accurate and I would expect it to be closer than a hand calculation (although we can fool it pretty easy).
They know the injector size, pulse width, RPM, time and speed. From that they can come up with a dang accurate MPG calculation that isn't related to when the gas pump shuts off when you fill up.
I hacked some of the earlier DICs for some engine swaps a few years ago and I couldn't see any reason their calculations would be wrong. There certainly wasn't a finagle factor in there to make it lie. The fuel remaining was pretty bad though since they had curves of the float assembly based on the fuel tank shape.
No doubt this was long before the HHR but there is no reason to change the method. So far, I haven't seen any difference that would make me think I can't trust the DIC numbers. It's my right foot that I don't trust!
They know the injector size, pulse width, RPM, time and speed. From that they can come up with a dang accurate MPG calculation that isn't related to when the gas pump shuts off when you fill up.
I hacked some of the earlier DICs for some engine swaps a few years ago and I couldn't see any reason their calculations would be wrong. There certainly wasn't a finagle factor in there to make it lie. The fuel remaining was pretty bad though since they had curves of the float assembly based on the fuel tank shape.
No doubt this was long before the HHR but there is no reason to change the method. So far, I haven't seen any difference that would make me think I can't trust the DIC numbers. It's my right foot that I don't trust!
02-09-2010, 01:20 PM
#7
Senior Member
Join Date: 12-24-2008
Location: N/A
Posts: 717
My most recent 10,000 miles(10-20) calculations and DIC are as follows:
DIC said 22.6 MPG
Actual was 23.84 MPG
I log all fill ups so this is easy to calculate.
First 10,000 miles were:
DIC said 21.3 MPG
Actual was 22.69 MPG
On long flat trips at freeway speeds I see on the DIC upwards of 33 MPG and less for everything else.
DIC said 22.6 MPG
Actual was 23.84 MPG
I log all fill ups so this is easy to calculate.
First 10,000 miles were:
DIC said 21.3 MPG
Actual was 22.69 MPG
On long flat trips at freeway speeds I see on the DIC upwards of 33 MPG and less for everything else.
03-01-2010, 12:44 PM
#8
Senior Member
Join Date: 07-10-2008
Location: Not necessarily Humbolt County
Posts: 421
My most recent 10,000 miles(10-20) calculations and DIC are as follows:
DIC said 22.6 MPG
Actual was 23.84 MPG
I log all fill ups so this is easy to calculate.
First 10,000 miles were:
DIC said 21.3 MPG
Actual was 22.69 MPG
On long flat trips at freeway speeds I see on the DIC upwards of 33 MPG and less for everything else.
DIC said 22.6 MPG
Actual was 23.84 MPG
I log all fill ups so this is easy to calculate.
First 10,000 miles were:
DIC said 21.3 MPG
Actual was 22.69 MPG
On long flat trips at freeway speeds I see on the DIC upwards of 33 MPG and less for everything else.
Going from Foresthill to the valley (Roseville/Sac) and back doing the speed limit I average right at 27. I took the SS to the Bay area and got 31 average round trip doing 70 where it was legal.
I have no complaints!
