kind of relieved to read that!
"Chasing MPG in my 80 series Lx450" How I increased my gas mileage.
- Thread starter GW Nugget
- Start date
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I just returned from a trip last week towing a empty cargo trailer. 12x6 single axle.
I have Toyo M55’s 255/85/16 @45psi and 50 psi on trailer tires.
I got 482km or 300 miles out of 82 litres of regular unleaded(87 octane).
$1.80 avg/litre
I get to 60/65 mph asap as I find that seems to be its best speed/mpg
Results were 13.61 mpg @60 mph. I’m happy with that!!
I have seen upwards of 18mpg @65 mph without trailer running P265/75/16 LTX Michelin tires prior to the LT255’s
All stock and baseline complete, with the exception of timing advanced a few degrees.
I have Toyo M55’s 255/85/16 @45psi and 50 psi on trailer tires.
I got 482km or 300 miles out of 82 litres of regular unleaded(87 octane).
$1.80 avg/litre
I get to 60/65 mph asap as I find that seems to be its best speed/mpg
Results were 13.61 mpg @60 mph. I’m happy with that!!
I have seen upwards of 18mpg @65 mph without trailer running P265/75/16 LTX Michelin tires prior to the LT255’s
All stock and baseline complete, with the exception of timing advanced a few degrees.
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Came across this guy a couple months back. Pretty amazing. IIRC he was averaging over 40 MPG with his 302 V8. Of course power was way down, but he said he had no problem maintaining 65 plus mph. I’m convinced science/engineering has purposefully made internal combustion engines inefficient. Also, lots of folks are saying they are getting worse fuel economy lately. I’m guessing they’re slipping in more ethanol into the fuel. When I first got my stk LX450, I was averaging 14-16L/100 kms in the summer and 16-18L/100 kms in the winter. I found it took a while for the diff oil to warm up in the winter which I’m sure killed fuel economy as did probably all other gear/driveshaft/driveline fluids/greases. I switched to synthetic diff fluid a while back which definitely helped in the winter. I’m surprised no one has mentioned air cleaner, points, spark plugs. It goes without saying all the above must be in tip top condition for max fuel economy.
davidp14
SILVER Star
interesting read. Thanks for posting @GW Nugget
I've done some very unscientific/lazy MPG estimates myself. Basically I just set the trip meter when I fill up and note # of gal filled.
I'm on 35"'s, 2.5" lift, with ARB, winch, sliders, and FULL wood drawers in the back. My motor has been pretty well baselined and all the prime suspects have been addressed.
I consistently get between 10 and 12.5 MPGs. 10 to 11 is more often 12.5 was on a long, hwy trip with not much hills and just me.
I would be shocked if I got close to 15mpg. good for you sir.
I've done some very unscientific/lazy MPG estimates myself. Basically I just set the trip meter when I fill up and note # of gal filled.
I'm on 35"'s, 2.5" lift, with ARB, winch, sliders, and FULL wood drawers in the back. My motor has been pretty well baselined and all the prime suspects have been addressed.
I consistently get between 10 and 12.5 MPGs. 10 to 11 is more often 12.5 was on a long, hwy trip with not much hills and just me.
I would be shocked if I got close to 15mpg. good for you sir.
I’ll throw my observations in here. I’m a religious MPG tracker, it turns driving slow into a fun game and filling up with fuel into a dopamine hit.
I’ve gotten 14-15mpg mixed, and 15-17mpg strictly highway with the 80 pictured below. 3FE, 5 speed swapped, header and 2.5” exhaust, de-smogged and in good tune. I drive easy and usually do 60-65 on the highway which is ~2500rpm with my gearing. 15-16mpg highway is achievable even loaded up to 6500lbs for a trip.
I had another 3FE 80 with similar mods but a little lighter, less lift and stock exhaust which did the same.
In-town only, or “carefree” (keep up with traffic) mixed driving averages in the 12’s.
Just goes to show that a gas-powered, kitted out 80 can still deliver respectable economy in touring-type use. My good friend’s similarly set-up auto HDJ81 only did 17-19mpg in the same kind of driving.
With the auto both 3FE’s were in the 11-13 mixed and 13-15 highway range.
The right gearing and a bit of patience seem to go a long way.
Curious what a bit of head work might do.
I’ve gotten 14-15mpg mixed, and 15-17mpg strictly highway with the 80 pictured below. 3FE, 5 speed swapped, header and 2.5” exhaust, de-smogged and in good tune. I drive easy and usually do 60-65 on the highway which is ~2500rpm with my gearing. 15-16mpg highway is achievable even loaded up to 6500lbs for a trip.
I had another 3FE 80 with similar mods but a little lighter, less lift and stock exhaust which did the same.
In-town only, or “carefree” (keep up with traffic) mixed driving averages in the 12’s.
Just goes to show that a gas-powered, kitted out 80 can still deliver respectable economy in touring-type use. My good friend’s similarly set-up auto HDJ81 only did 17-19mpg in the same kind of driving.
With the auto both 3FE’s were in the 11-13 mixed and 13-15 highway range.
The right gearing and a bit of patience seem to go a long way.
Curious what a bit of head work might do.
I track my MPG, stopped dailying my 80 two years ago and that made the best difference. Saved me an average of $450 a month. Thing still continues to average 12.6mpg. All around town tanks are usually in the mid 11s and all highway tanks are about 14. It's done that while running poorly and just after a tuneup haha, it's very consistent.
Where I live in the fall the gas stations switch to winter blend, which isn't as efficient. Add in colder [denser] air that your pushing your vehicle through increases drag on the vehicle. My work truck gets 13.5L/100km or 17.5 mpg in the summer and 18L/100km or 13mpg in the winter....
