TCCoA Forums banner

181 - 200 of 302 Posts

·
Registered
Joined
·
32 Posts
Engine: 4.6 V8
Combined MPG: 21
City MPG: not in the city enough
Highway MPG: 24 with the cruise on.
Fuel Used: 87
Average highway speed: around 70
Average Climate: moderate mid Atlantic
Mechanical Mods: All stock
Mileage on the engine: around 15,000mi when I last checked
 

·
Voice/Data Guru
Joined
·
7,781 Posts
Nice bird you have Keifer :) But your Hwy mileage I would think should be higher mine was getting 27 to 28 before my Mods , Maybe yours just needs to get broke in more ;)
 

·
Registered
Joined
·
975 Posts
Baseline (before mods)

Engine: '95 4.6
Combined MPG: 19
Highway MPG: 23
Fuel Used: 87
Average highway speed: 65
Average Climate: Midwest (Summer)
Mechanical Mods: none
Mileage on the engine: 75,000
Comments: Stock power train, 3.08 rear gears

After mods:

Engine: '95 4.6
Combined MPG: 21
Highway MPG: 22.5
Fuel Used: 91/93
Average highway speed: 65
Average Climate: Midwest (Summer)
Mechanical Mods: PI Headswap, 3.27 rear gears
Mileage on the engine: 80,000
Comments: Tuned for 91 octane due to that being all that is available in some areas I drive
 

·
Faster than Porkchop
Joined
·
2,037 Posts
I'm getting the worst millage here for reasons unknown, I haven't done the math but
with my 4.10 ,pi heads,intake , true duals I was getting 250 miles per 14-15 gallons.

now with the stock 3.27's i'm getting 225miles if I'm lucky mostly driving 70 mph on the freeway.

I'm pissed about this now. when I run my stock tune I got pinging, with the tune no pinging and I can let them tires burn for a little while flooring it with the 3.27's.

I'm going to go back to the stock tune next fill up and see if i can get my 300 miles per tank like how it used to be but I doubt it.
 

·
Registered
Joined
·
32 Posts
Nice bird you have Keifer :) But your Hwy mileage I would think should be higher mine was getting 27 to 28 before my Mods , Maybe yours just needs to get broke in more ;)
Thanks! :)
Yeah, I only had it on one long trip the whole time I had it. That's when I got 24 out of it. Other than that, it gets around 21 on avg. It's less than 20,000 mi old right now.
These cars do pretty good for V8s MPG wise.
 

·
Registered
Joined
·
975 Posts
I'm getting the worst millage here for reasons unknown, I haven't done the math but
with my 4.10 ,pi heads,intake , true duals I was getting 250 miles per 14-15 gallons.

now with the stock 3.27's i'm getting 225miles if I'm lucky mostly driving 70 mph on the freeway.

I'm pissed about this now. when I run my stock tune I got pinging, with the tune no pinging and I can let them tires burn for a little while flooring it with the 3.27's.

I'm going to go back to the stock tune next fill up and see if i can get my 300 miles per tank like how it used to be but I doubt it.
250 miles per 14 gallons = 17.86 mpg

The 3.27s don't do that well city, but are good on the highway at a consistent 60mph.
 

·
Super Moderator
Joined
·
9,152 Posts
I've been seeing 18-19ish on the Bird in the city after my mods, highway has been 23-25. Before the mods I was used to 20-21 city and 26-28 highway; saw as high as 30 once.
 

·
Registered
Joined
·
975 Posts
I've noticed a modest increase around town, but very little change on the highway. 22.5 was the hwy mileage headed to/from Iowa several times. My drive to and from work is a good mix of city and highway and still a consistent 21 mpg from 19 before (but that was on 3.08s). I should have checked the mileage with the 3.27s before the headswap.
 

·
Premium Member
Joined
·
5,862 Posts
Over 25 mpg...

Well, I had to take Daniela to the city today for a doctor's appointment to get her foot x-rayed and I decided to check the mileage. I used the Garmin since the odometer doesn't work (and I'm sure it's MUCH more accurate anyways). I also filled up on the same pump at the same station to make sure everything was exactly the same and more accurate.

Well, I reconnected the EGR valve and I guess it does increase the MPG quite a bit (3, 4, and 5th tanks were with it disconnected)...

UPDATE: Ok, after CAI added, I checked mileage on multiple tank fulls of fuel:
1st Tank: 26.1 Avg MPG
2nd Tank: 27.9 Avg MPG
3rd Tank: 25.4 Avg MPG (EGR disconnected)
4th Tank: 25.9 Avg MPG (254 miles on 9.8 gallons of fuel)
5th Tank: 25.5 Avg MPG (178.6 miles on 7.0 gallons)
6th Tank: 29.2 Avg MPG (213.2 miles on 7.3 gallons) (EGR RECONNECTED) some spirited driving - went to visit 'cobra R Thunderbird' in Tally.
7th Tank: 28.5 Avg MPG (356 miles on 12.5 gallons) all highway drove north of Clanton, Alabama.

Running Average: 27.3 MPG
 

·
Banned
Joined
·
241 Posts
i just put back on few stock parts and got exactly 22.97 miles to the gallon, 25 city 75 freeway...and id get on it here and there....not bad for a v8
 

·
Registered
Joined
·
2,134 Posts
Last time I went from Murfreesboro, TN to St. Louis, MO which is about 350 miles door to door I can almost make it into the city limits on one tank doing 80mph. The book says 18 gallon tank but to be honest I don't think I've ever put more than a little over 16 gallons in it to fill it up. Which puts my mpgs at just under 22.. damn and you guys are averaging 25, 26?? I gotta have a clogged cat or something..

i put under-drive pulleys on and i felt like i picked up maybe 1 mpg but ill prob have my 373 gear before i can actually test it out which according to most ill loose another 2-3mpgs
 

·
Super Moderator
Joined
·
9,152 Posts
After I put the front end together after replacing the LCAs I had about 4 degrees of toe in (according to the shop). According to my scangauge I was getting 20-21 MPG cruising at 40 MPH. On the way back after the alignment I was seeing 26-28, even with the 3.73s. So obviously a misaligned front end will cause your mileage to tank! Apparently the wider tires caused more grip on the road with the bad alignment creating more toe-in resistance for the vehicle to power through, which I guess explains my mileage drop after switching to the 255 wide tires.
 

·
Premium Member
Joined
·
5,862 Posts
After I put the front end together after replacing the LCAs I had about 4 degrees of toe in (according to the shop). According to my scangauge I was getting 20-21 MPG cruising at 40 MPH. On the way back after the alignment I was seeing 26-28, even with the 3.73s. So obviously a misaligned front end will cause your mileage to tank!
Well, duh! Take a little matchbox toy car, bend the front wheels in slightly (to signify toe-in) and try to roll it. Hmmmmm. Funny how plowing takes so much work lol (also wears your tires on the outside edges).

Speaking of MPG, I gotta take some new readings since I've eliminated my EGR circuits (Daniela kept complaining the car was 'surging' and I knew that was the EGR system screwing up, so I disconnected it).
 

·
Super Moderator
Joined
·
9,152 Posts
Yeah, I didn't have the mind to think of that until they told me I had a nasty case of toe-in. Amazing how much symptoms fit together when you know the problem! And my tires were actually wearing pretty bad on the inside, outside looks good. :zdunno:
 

·
Voice/Data Guru
Joined
·
7,781 Posts
And I got back from RobertP's place today 180 mile round trip & SG said 28 mpg with my 3.73 and high HP :eek:
 

·
Premium Member
Joined
·
5,862 Posts
And I got back from RobertP's place today 180 mile round trip & SG said 28 mpg with my 3.73 and high HP :eek:
Y'all running the Scan Gauges, are these numbers you're giving us the AVERAGE or just INSTANTANEOUS readings?

Yeah, I didn't have the mind to think of that until they told me I had a nasty case of toe-in. Amazing how much symptoms fit together when you know the problem! And my tires were actually wearing pretty bad on the inside, outside looks good. :zdunno:
That's different. Usually when inside wears, it's indicative of tires toed OUT too much (or too much negative camber).
 

·
Super Moderator
Joined
·
9,152 Posts
I have mine set to give me instantaneous (the high figure I gave) as well as a trip average. I have yet to go on any trip of over 5 miles, so the highest average reading I've seen has been 21 (this is city driving).
 

·
Premium Member
Joined
·
5,862 Posts
I have mine set to give me instantaneous (the high figure I gave) as well as a trip average.
Well, that's CHEATING! lol All my figures are averages based on tank fulls (or close to). On my Dodge van, I can let off the gas going down the highway and my INSTANTANEOUS will read 99 mpg!
 
181 - 200 of 302 Posts
Top