MPG Machine
Joined: Mar 2007
Posts: 1,141
Likes: 48
From: Saskatchewan, Canada - where arguing "DA" is for the slow and weak...
Our LeMans wagon is going to be backed by a 4L60E, 3.08 gears and 28" tall tires... should do well on the highway. Project cost is estimated at $10-12K.
Miatas are about as dorky as it gets IMHO... 
Rx7 swaps are the way to go! Look at norotors.com for ideas. The engine bays are huge in the 86-91 models.
When I had the 2.73's in my 86 RX7 with the 200-4R OD trans and L/U converter I would see over 30mpg highway at 70+ and click off mid 10 second 1/4 mile passes.
Had a mildly built 3.8 (buick grand national motor).
Very comfortable to drive. Sold it for $6500. Was roughly 2750lbs with out driver.
Rx7 swaps are the way to go! Look at norotors.com for ideas. The engine bays are huge in the 86-91 models.
When I had the 2.73's in my 86 RX7 with the 200-4R OD trans and L/U converter I would see over 30mpg highway at 70+ and click off mid 10 second 1/4 mile passes.
Had a mildly built 3.8 (buick grand national motor).
Very comfortable to drive. Sold it for $6500. Was roughly 2750lbs with out driver.
Last edited by Forcefed86; Jan 21, 2014 at 03:18 PM.
Just buy a used VW diesel off craigslist for about $3k and be done with it. 45-50mpg. Do a muffler delete and a cold air intake. Burnouts are easy and the straight pipe turbo sounds cool too. Upsolute performance can burn a chip for the factory ECU for better performance.
That is the most logical and practical answer on here.
You should be kicked off this board immediately.
You should be kicked off this board immediately.
Just buy a used VW diesel off craigslist for about $3k and be done with it. 45-50mpg. Do a muffler delete and a cold air intake. Burnouts are easy and the straight pipe turbo sounds cool too. Upsolute performance can burn a chip for the factory ECU for better performance.
Miata, 240sx or rx7 would be my choice.
Put in an aluminum 4.8, t56 and 2.73 gears.
Wouldn't be surprised if you could pull mid-high 30s with that thing and still scoot pretty well due to the power/weight ratio.
Put in an aluminum 4.8, t56 and 2.73 gears.
Wouldn't be surprised if you could pull mid-high 30s with that thing and still scoot pretty well due to the power/weight ratio.
what are some ways to actually get better mileage with the yukon?
would it be possible to add a tune that would get better mileage? less fuel at cruise and idle?
There are some things within the engine, exhaust, drive train and PCM calibration that can help a good bit but in the end it's still a brick wall from an aerodynamic perspective.
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Verdad Gallardo Perhaps go fast should throw up his mpg and vehicle weight as a sample of what can be done with a custom tune. Plz don't mention who did the tune or how it was done as the tuner is not a sponsor.
Although it's probably a tad outside the 12k budget, an early 2000's 6 speed Corvette, as G Body said, would be my choice! They get around 30 mpg on the highway. If you're dead set on doing a swap though, you could put a 4.8 in it! Probably have the only one of those around.
OR, you could just get one of those hydrogen generator things that I have to hear about from my neighbor every time he comes over. His Jeep Liberty gets like 100 mpg or something. LOL!
OR, you could just get one of those hydrogen generator things that I have to hear about from my neighbor every time he comes over. His Jeep Liberty gets like 100 mpg or something. LOL!
I just bought a 99 vette 6spd last year. (for 12k actually!)
While it does get 30mpg or so crusiing 70 in 6th, I still average 15mpg or so by the time you figure city driving in. If I baby it a week I can average 18mpg. Still not great IMO. Something lighter weight with a taller gear is the way to go.
While it does get 30mpg or so crusiing 70 in 6th, I still average 15mpg or so by the time you figure city driving in. If I baby it a week I can average 18mpg. Still not great IMO. Something lighter weight with a taller gear is the way to go.
Teching In
Joined: Nov 2013
Posts: 40
Likes: 0
my suburban (04 2wd 5.3L) is averaging about 12-13 mpg city/highway lol i really thought it would get a little better then that but its been super cold so i think thats made a bad difference
also i think my clutch fan is on all the time. im really considering a swap to electric fans
also i think my clutch fan is on all the time. im really considering a swap to electric fans
my suburban (04 2wd 5.3L) is averaging about 12-13 mpg city/highway lol i really thought it would get a little better then that but its been super cold so i think thats made a bad difference
also i think my clutch fan is on all the time. im really considering a swap to electric fans
also i think my clutch fan is on all the time. im really considering a swap to electric fans
IMO cheapest and easiest way on your current rig would be to buy cheap tires as narrow and tall as you can fit. Then run alot of tire pressure.
11 Second Club
Joined: Sep 2011
Posts: 390
Likes: 2
From: The Burnie, MD
It's going to be tough to find a car that's lighter and is as easy to swap as the Miata. I'm running a 3.23 rear so it'll cruise at 80mph at 2K rpm. I've never kept my foot out of it long enough to get an accurate mpg, but I'd imagine it would be pretty good.
Teching In
Joined: Nov 2013
Posts: 40
Likes: 0
well my thoughts are if the fan is dragging the motor down that could cause a loss of mpg
i had a 5.0 mustang years ago that had a clutch fan that went out. it was doing the same thing my burb seems to be doing, sounds like an airplane driving down the road. i picked up 3 mph at the track taking it off, thats basically 30hp
im sure your probably right though, probably wont make that much difference but i figured every little bit would help
i had a 5.0 mustang years ago that had a clutch fan that went out. it was doing the same thing my burb seems to be doing, sounds like an airplane driving down the road. i picked up 3 mph at the track taking it off, thats basically 30hp
im sure your probably right though, probably wont make that much difference but i figured every little bit would help
I have thought of building a mpg ls car. I would do it to prove you can do it, not to save money. If it was done to save gas you're so far in the hole to start you will never make it up. I think you could build a turbo 4.8 in a 240 and get 25 mpg on the hwy and run low 11's fairly easily.
1997 Thunderbird lowered 1.5 to 2" with 16" factory size wheels:
Gen III 5.3, electric fan, 4L60E with a junkyard transmission cooler, 3:23 gear with "411 style" custom tuned PCM using a 99 Corvette intake, LS6 valve springs and a Muscle Car oil pan kit. True 2.5" dual exhaust into 2.25" factory Thunderbird mufflers using some butchered and hacked (i.e. poor flowing) C5 corvette manifolds up front. Modified aftermarket custom air intake for a 99 Silverado.
I feel there is room for improvement if I build some good flowing short or mid length headers (nothing factory fits) and adjust the air intake to work as a "cold air" / ram air setup at speed. Right now the intake picks up some bleed through air from inside the engine compartment if stationary, however while moving the air temps stay within 3 - 5 degrees of ambient.
Full details on the car and budget are in my signature.
