Straight Piped part II

[Maverick]

The software won't let me post on my thread so I'll start a new one.

Someone asked a question about having a mileage improvement with the straight pipe.

I had to run to Fairbanks, Alaska from Anchorage on Friday morning. I had a previous best of 18.4 mpg with my 2500HD. This trip yielded a best so far of 19.6 mpg. Mostly 70 mph. Filled up in Fairbanks and came home to Wasilla (310 miles). I still have 1/2 tank left. This tank may be better than my 19.6 tank. Looks like to me I have a mileage gain. Good deal.

[Camstyn]

I straight piped mine a little over a week ago. I only have ~1000 miles on the truck, but have made two trips from Agassiz to Ashcroft and return, one with stock exhaust and one again with the straight pipe. It's about a 300 mile trip.

On the first trip the DIC said I got 23.7mpg, on the second trip it said 23.0mpg. I don't see why I would lose mileage with the straight pipe, maybe it was because of the heavier traffic or the strong headwind on the way home..

Cam

[56Nomad]

Camstyn,

I think you're the first person to report over 23 MPG onTDP

Must be downhill route for you :D :D :D :D :D :D :D

Inbelievable

[Camstyn]

I crap you not, I can hardly believe it myself. There is a lot of up/down, and it's a return trip that starts and finishes at the same elevation so it's not more downhill than uphill. I just set cruise control at the speed limit. Approx. half of the trip the speed limit is 90kph (55mph) and the rest of 100kph (~62mph) so the truck seldom sees 2000rpm's on this particular drive.

If anyone would like proof, I'll do the trip again this coming Friday and video-capture my DIC display upon completion, and post a link of it in .MOV format..

I've only got 1200 miles on the odometer so far, maybe once it's more broken in I'll hit 25mpg since I hit just shy of 24 on the first tank. :eek:

My complete average so far is 20.8MPG, which has been alot of running around town and idling.

FWIW, my 2002 van with the 6.5 diesel consistently gets 19.5mpg on this same trip, same driving habits. I'm getting these numbers calculating in US gallons, not imperial, so there's no confusion. :D

[56Nomad]

Camstyn,

Ahhh, I see you live in Canada and have
the big gallon of gas. Thats why your numbers
are so good :rolleyes: http://members.cruzio.com/~quailman/volume_conv.gif

[ 08-04-2003, 08:31 AM: Message edited by: 56Nomad ]

[TooMuchMuscle]

Those dang Canadian's... Just Kidding... I'll stand with him on this one... I went from AZ to CA and averaged 22.7 mpg on the trip. I never went over 65 and the truck had 15,000 miles on her. these trucks do great if you can stay off the floor.

[Camstyn]

I'm in Canada but the DIC on my truck, when set in English mode, reads the US gallons (3.79 liters). My claimed 23.7MPG is using US gallons, locally I can brag 28.4mpg for my duramax and 23.5 for the 6.5 diesel while using imperial gallon measurements.
FWIW I've checked at the pump and it's accurate, I always use the same nozzle of the same pump, parked on the same side. When I'm not able to do that I know that my calculation won't be precise, so I don't bother.

I'll let you know how I do tomorrow night when I get back. :D

[MAV (formerly Maverick)]

This last tank turned out to be 20.5 . I'm happy with that.

Look at the first post. The forum lost my identity in its little vacation. New name (almost).

[NickLeinonen]

i never ever use imperial gallons [cause i haven't the slightest clue what it is.] when i figure out my fuel economy numbers, i figure them out in liters per 100km and from there i can comvert them to gallons per 62.1 miles and from that it can be comverted to miles per gallon. and when i think or speak of gallons, they are always the us type. the imperial gallon is something that i have never ever seen yet around here, and hopefully something i will never see... useless... liters are better i think [22 year old so i never learned anything other than liters and metric in school]