What would cause a 5mpg gain in city driving?
#1
TECH Fanatic
Thread Starter
iTrader: (9)
Join Date: Dec 2006
Location: Va Beach
Posts: 1,240
Likes: 0
Received 0 Likes
on
0 Posts
What would cause a 5mpg gain in city driving?
Lately have been seeing 13's around town and my rear bumper gets very dirty very quickly. I was still seeing 26ish on the highway.
Tonight I reset the average and took the car out for dinner and a beer. Averaged 18 mpg driving all city and not being super easy on the car.
Last weekend I changed my oil... it had 5000 miles on it, but it had been about 14 months since changing it because of my whole targa project etc. I was considering pulling my oil cooler so was going to change it then, but have decided to keep the Dewitts stuff.
So car got all fresh oil... cracked the oil cooler line to drain that too.
Also, found that my catch can was 100% full of mostly water from condensation. I find that this happens in the winter, but I've never accidentally let it get this full. Could that have anything to do with it... I'd think if I had a PCV block I'd be blowing the dipstick out... which it wasn't.
Could any of that have an effect on my aroudn town efficiency?
Thanks,
Brian
Tonight I reset the average and took the car out for dinner and a beer. Averaged 18 mpg driving all city and not being super easy on the car.
Last weekend I changed my oil... it had 5000 miles on it, but it had been about 14 months since changing it because of my whole targa project etc. I was considering pulling my oil cooler so was going to change it then, but have decided to keep the Dewitts stuff.
So car got all fresh oil... cracked the oil cooler line to drain that too.
Also, found that my catch can was 100% full of mostly water from condensation. I find that this happens in the winter, but I've never accidentally let it get this full. Could that have anything to do with it... I'd think if I had a PCV block I'd be blowing the dipstick out... which it wasn't.
Could any of that have an effect on my aroudn town efficiency?
Thanks,
Brian
#6
TECH Enthusiast
iTrader: (8)
Join Date: Sep 2006
Location: Elk Grove, CA
Posts: 696
Likes: 0
Received 0 Likes
on
0 Posts
Are you only going by the DIC or are you actually calculating it? I have heard the one on the DIC sometimes isn't the best to go by. Take my Denali for instance one day it will tell me I am getting an average of 16mpg then the next day it is showing like 10.8 but the driving, distance, and everything is generally the same go figure. One thing is constant though is the distance between fill ups. So I basically stopped going by it.
#7
TECH Fanatic
Thread Starter
iTrader: (9)
Join Date: Dec 2006
Location: Va Beach
Posts: 1,240
Likes: 0
Received 0 Likes
on
0 Posts
Just using the DIC... car used to always show around 19 city when it was mostly stock. After the cam it was 15-17 all the time. Then for awhile it was 13s which was wierd to me.
I'll have to check it manually when I finish this tank off.
I'll have to check it manually when I finish this tank off.
Trending Topics
#8
TECH Enthusiast
iTrader: (8)
Join Date: Sep 2006
Location: Elk Grove, CA
Posts: 696
Likes: 0
Received 0 Likes
on
0 Posts
Ya mine tells me I am making 28mpg with a 408 stroker most of the time but we all know that can't be right I haven't tried checking mine manually yet though. Be interesting to see how close it really is though.
#13
On The Tree
Join Date: May 2003
Location: Kennesaw, Ga
Posts: 129
Likes: 0
Received 0 Likes
on
0 Posts
As others have said... the dic's reading does vary.
I notice a measurable drop in mileage with the alcohol blended high test.
C5 Z06's... I averaged ~18/20 in town, ~ 24-28 highway.
Once I got as high as 30 mpg. going all the way to Sebring... but we were running 70/75 mph. for the guys pulling trailers.
C6 Z06 gets ~ 17/19 in town, 23-26 highway.
My right foot has been known to influence these results.
I notice a measurable drop in mileage with the alcohol blended high test.
C5 Z06's... I averaged ~18/20 in town, ~ 24-28 highway.
Once I got as high as 30 mpg. going all the way to Sebring... but we were running 70/75 mph. for the guys pulling trailers.
C6 Z06 gets ~ 17/19 in town, 23-26 highway.
My right foot has been known to influence these results.
Last edited by trumperZ06; 12-18-2008 at 03:49 PM.
#17
Hey guys. So im not sure where everyone is. Im located in Phx AZ and i have a 2000 m6 with a cat back sys and an intake and im getting 21 in town and 33 on the highway. And i leave every light like im being chased. I thought this was normal for this car, but it seems like everyone is getting a lot less
#18
TECH Fanatic
Thread Starter
iTrader: (9)
Join Date: Dec 2006
Location: Va Beach
Posts: 1,240
Likes: 0
Received 0 Likes
on
0 Posts
Your car is stock... put a big cam in there and get back with us
Oh... my car is down to 14.7 average for this same tank of gas now. The other night when I was driving it I wasn't sitting in traffic at all and never really got stopped at any lights. Now w/ more stop/go etc. I've watched it fall from 18 to just below 15. Oh well... not really a big deal.
Oh... my car is down to 14.7 average for this same tank of gas now. The other night when I was driving it I wasn't sitting in traffic at all and never really got stopped at any lights. Now w/ more stop/go etc. I've watched it fall from 18 to just below 15. Oh well... not really a big deal.
#20
TECH Fanatic
Thread Starter
iTrader: (9)
Join Date: Dec 2006
Location: Va Beach
Posts: 1,240
Likes: 0
Received 0 Likes
on
0 Posts
Yeah... tell me about it... averaging 14 this tank so far after filling up at lunch. No biggie.... seems pretty much normal for around town driving w/ this size cam. Its no t-rex, but its not small. The G5-X2 specs out at 232/240 .595/.608 and mine is on a 114 lobe.
The next step for this car will be some AFR 205 milled to 59cc. That should get some of the overall gas mileage back.
The next step for this car will be some AFR 205 milled to 59cc. That should get some of the overall gas mileage back.