"Chasing MPG in my 80 series Lx450" How I increased my gas mileage. (1 Viewer)

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Purely for data point sake...definitely a flyer
30" 265/70 16s and maybe 120# in the back,
45mi, 2-way (90mi total, N/S), flat-ground run
@65mph on interstate
@5500ft
on 88 non-eth
in 95deg ambient
gets repeatable 18.5mpg.
Calculations were made using the stock odo, phone gps, and refuel amount at the same pump before and after. edit: oh and compensation for tire size to 285/75 ~2.6% to adjust odo mileage.
Can't repeat it now w/o unloading 600#.
Plus it's irrelevant with a load-out of anything significant, so most of us are happy with 11-13mpg.

On the trail it's gph.
And with some luck I can get 24hrs run time on a single tank - which is usually about 125mi. :facepalm:
 
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Purely for data point sake...definitely a flyer
30" 265/70 16s and maybe 120# in the back,
45mi, 2-way (N/S), flat-ground run
@65mph on interstate
@5500ft
in 95deg ambient
gets repeatable 18.5mpg.
Calculations were made using the stock odo, phone gps, and refuel amount at the same pump before and after.
Can't repeat it now w/o unloading 600#.
Plus it's irrelevant with a load-out of anything significant, so most of us are happy with 11-13mpg.

On the trail it's gph.
And with some luck I can get 24hrs of run time on a single tank - which is usually about 125mi. :facepalm:


I've yet to do a full day in the trail but I'm hoping for 250ish. We'll find out when I finally get to run wabdr. Maybe next year
 
😂 On my last hard core trail ride Fordyce Creek it took a day and a half and over a half tank of gas to go 12 miles.
Or about 1 mile to the gallon.
Smiles per gallon were off the chart!!
Fuel is the cheapest part of this hobby 🤷‍♂️
 
Has any one tried the electrolysis / hydrogen injection into the air intake?
I have a friend who made the system in his house (I know !)
Its basically a cell with distilled water through electrolysis it introduces hydrogen (there are extreme examples from small amount to enhance fuel to large amount almost like a fuel additive) and is pushed in with air intake.

I am not entirely sure on the system but figured to post and ask if its just myth or did any one try it successfully.
 
Electrolysis wouldn't seem to be practical as the process would require a rather significant electrical current to generate only small amounts of hydrogen and oxygen at low pressure. In addition to distilled water an electrolyte has to be added to make the solution conductive. Safe storage of the gases would be an issue.

More practical would be methanol and/or water injection which is typically used for cooling intake charges on forced induction motors.
 
More practical would be methanol and/or water injection which is typically used for cooling intake charges on forced induction motors.

Not even familiar with water injection .... i will google it :D thanks !
I thought it sounded too good to be true.
 
The ability to modify ignition timing can give pretty good increases in fuel mileage. Especially during highway cruising rpm ranges. You would need a way to either reflash the ecm, or use a piggyback ecu to do so. Factory ignition timing maps are usually rather conservative and leave a fair bit of performance and efficiency that is missed out on. Also porting a cylinder head should give greater engine efficiency. With so many head gaskets being done I'm surprised most don't consider porting the head. Also a free flowing exhaust from cylinder head to tail pipe can also improve efficiency and should improve gas mileage.
 
Electrolysis wouldn't seem to be practical as the process would require a rather significant electrical current to generate only small amounts of hydrogen and oxygen at low pressure. In addition to distilled water an electrolyte has to be added to make the solution conductive. Safe storage of the gases would be an issue.

More practical would be methanol and/or water injection which is typically used for cooling intake charges on forced induction motors.


Superb test showing exactly how HHO doesn't really effect anything for the car, I guess the only thing missing from that test is engine output which i dont think will change any way.
 
Full HHO if done correctly & lots of constant tweaking does work, but haven't seen great results with the HHO assist kits.
All my experience is from watching videos.
There are major car manufactures making great strides with the Hydrogen engine, but they still will want you to fill it up at the fulling station rater then letting you make you own hydrogen in the vehicle. I'm sure it will be said to be to dangerous. :meh: :steer:
Enough said.
 

We've been over this before. Please take careful note of the teflon application and landtank's intake tube height mods.
 
Pulled front shaft to confirm some stuff for a DC shaft, so took the opportunity to cruise and see what max “road trip“ mpg could be if I had a part-time kit (not installing one, just curious) and light load. ‘97 on Js w/ 315 Toyo AT3 @ 33psi, stock gearing, no armor/etc. Yellr box correction, odo confirmed with GPS. All fluids/grease/baseline/tune up stuff is up to date, truck runs great. Topped off at same pump, etc. I go by fill-ups, not scangauge average. Sea level, no AC, mostly flat with a few short & mild grades. 17.25mpg doing 55-60mph - dang! Did the same cruise when buying the truck, was still in good shape but is slightly more up to date now & had front shaft in. Got 15.5 then, so that’s more realistic. To reiterate, clearly this is an unrealistic setup for most 80 folks, and I was in ideal cruising conditions, just wanted to test. Still, wasn’t expecting more than 16. My mixed average usually ranges from 12.5-13, but can hit 13.5 in winter when my drives are longer.

Planning a road trip up to Denali next year, and I calculate rough cost of gas based on normal mixed MAX, so anything more than that 13.5 is what I’d consider good. Could take the girlfriend’s stock ‘04 4Runner for mpg & buttery ride, but naturally it has to happen in the cruiser for a variety of reasons. I’ll do this again with new shaft installed to see what we get & maybe simulate our trip load. IDGAF about the small $$ differences in mpg of an 80 - you can’t put a price on experiences - I’m just curious.
 
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A part time kit would also include (un)locking hubs which would further reduce drag on the front. Just pulling the shaft sees the axles and diff still being 'driven' by the front wheels.
 
True, and I understand that. I’m not at all considering the conversion either way, just wanted to see what I could squeeze out of the 1fz if I made it as easy on the truck as possible, without doing actual modifications.
 
I believe that removing the front drive flanges and the front drive shaft -- along with locking the transfer case, of course -- would yield the exact same results as a part-time conversion with free-wheeling hubs. One could do this for, say, a long drive to an off-road excursion, reinstalling the flanges and shaft at the trailhead. It's really not a difficult task, just a bit grubby.

The only problem is contamination. Maybe take some used flanges and "mill" (i.e. butcher with a die grinder) the teeth out of the flanges. Or 3D print some covers.

Just a thought for people who want to eek out a little more efficiency on their way to Cruise Moab, or whatever, while maintaining the advantages of the factory setup.
 
I was thinking about that after the cruise. If I really needed to squeeze out as much mileage as possible, and knew I was going to be on pavement the whole time, I wouldn’t have a problem pulling the shaft temporarily.

That said, although not a massive difference, I did miss the drive from the front wheels re: handling
 
I drove mine for around 3 months sans front shaft due to a noisy diff. As you say, loss of drive to the front was certainly noticeable when driving briskly in corners.

Upside was a lot less driveline backlash (manual transmission) and a slight gain in fuel economy on the freeway.
 
I drove mine for around 3 months sans front shaft due to a noisy diff. As you say, loss of drive to the front was certainly noticeable when driving briskly in corners.

Upside was a lot less driveline backlash (manual transmission) and a slight gain in fuel economy on the freeway.
I am amazed at those mpg. Was interested what the 80 could do. In my 2h 1988 troopy I can get 11km/l or 25mpg if I travel at 90kmh or 56mph. Slow but less fuel. Diesel that is.

In Oz diesel is usually $2 aud per liter, and of late petrol $1.8 per liter, or $5.2 usd per gallon of diesel, which is a little more than what folks in the US pay I believe.
 
You had me at 25mpg OG troopy diesel
yeah, I keep doing the mpg to km/l conversion on google. At worst on hwy if I travel 110kmh or 68mph I get 8km/l which is 18mpg.

Just miles apart from what you guys are getting.
Must admit everyone overtakes me and blows me off at lights, but quite a different consumption for sure.

I really monitor and calculate with odo and how many litres when I fill up. Always aiming at 11km/l, rarely over take, 90kmh.
10km/l at 95kmh.
No bull.

If I tow my tandem with 1.5 t ish, I get about 6km/l or 14mpg at worse. Traveling slow in 4th gear.
Now I am not disappointed with that anymore on.
Love old diesels with fresh injectors.

I guess you guys are constant 4wd in 80 series? Jeez, learn lots here, rarely go to 80's section but a fella wanted to convert to constant 4wd in a 70 series, they all said to use 80 series gearbox. Then I noticed chasing mpg in the latest postings...
 
I am amazed at those mpg. Was interested what the 80 could do. In my 2h 1988 troopy I can get 11km/l or 25mpg if I travel at 90kmh or 56mph. Slow but less fuel. Diesel that is.

In Oz diesel is usually $2 aud per liter, and of late petrol $1.8 per liter, or $5.2 usd per gallon of diesel, which is a little more than what folks in the US pay I believe.

It's about what I'm paying now. I think it was $5.05 when I drove by the station after work.

I see a consistent 17.5-18 commuting my diesel 80 and have seen 20.5 driving 65 on the freeway for a full tank of diesel.

This is with 315s and stock gears.
 

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