V8 MPG curves

[aeathb]

I have a v8, and because we don't have an instantaneous MPG monitor, I can't tell which rpm in 5th creates the greatest amount of MPG. I have searched everywhere for specifics on the 4runner tq/hp curves, and nothing comes up. I'm not looking to rival a Prius, but when I drive 8K+ miles around the country this summer, it all adds up. There are many web articles about how if you drive over 55 you kill your gas mileage, and when you see which car they based it on, its always the heavy 4 speed mini van with the std 4 cyl and they loaded bricks in the back; yea, of course they get 55mph as max. I know a couple of the guys on the forum put in vacuum gauges so maybe they know? Thanks

 

[eskimochaos]

I have a v8, and because we don't have an instantaneous MPG monitor, I can't tell which rpm in 5th creates the greatest amount of MPG. I have searched everywhere for specifics on the 4runner tq/hp curves, and nothing comes up. I'm not looking to rival a Prius, but when I drive 8K+ miles around the country this summer, it all adds up. There are many web articles about how if you drive over 55 you kill your gas mileage, and when you see which car they based it on, its always the heavy 4 speed mini van with the std 4 cyl and they loaded bricks in the back; yea, of course they get 55mph as max. I know a couple of the guys on the forum put in vacuum gauges so maybe they know? Thanks

I get best mileage 75-85.

Anything between 2.25k and 2.5k is the sweet spot for me. Then again I really dont care about gas mileage - I average 15 a tank.

 

[M1911]

Get a scangauge

 

[CJ3Flyr]

It's not instant but simply resetting the avg mpg display will give you a pretty good idea. Just do it in 5mph increments or...

 

[riverider]

The V8s get their best MPG when their V8 engines are turned off.olice: Want good MPG? dump the V8s and get a nice V6. :bigok: Oh that advice is FREE don't send me any money.:lmao:

 

[Sporin]

2006 V8 SR5 4WD, stock.

On the highway, 70mph, I see around 18 on the computer, a bit less if it's very hilly, a bit more if it's flat.

However, if I keep it in the 45-55 range the computer averages 20+. There's a long drive I take from my home to my relatives in Maine, it's mostly on NH 202, a nice secondary road that varies from 35mph in town to 55 between towns, very little traffic. I reset the MPG display when I start and 2 hours later my average is as high as 23mpg.

My weekly commute is a mix of around town, 50 mph secondary roads and rural highway, very little traffic. My computer generally averages between 18 and 19 over the course of a tank.

 

[aeathb]

It's not instant but simply resetting the avg mpg display will give you a pretty good idea. Just do it in 5mph increments or...

I was thinking about this too, but I wasn't sure how accurate it was, but I will try it anyways. Does anyone find its off by a lot? I need just a ballpark really.

The V8s get their best MPG when their V8 engines are turned off. Want good MPG? dump the V8s and get a nice V6. Oh that advice is FREE don't send me any money.

I will be towing a 3.5K lb pop up camper, so I'm pretty sure I would average higher in the v8 than the v6. At altitude and mountain passes, the v6 would strain pretty hard. I will keep my v8 thanks very much.

On the highway, 70mph, I see around 18 on the computer, a bit less if it's very hilly, a bit more if it's flat.

Mines a 2wd, but I will play with it a bit without the trailer and see what happens.
I think someone should invest in a professional grade dyno to get the curves. :dancin:

 

[eskimochaos]

The V8s get their best MPG when their V8 engines are turned off.olice: Want good MPG? dump the V8s and get a nice V6. :bigok: Oh that advice is FREE don't send me any money.:lmao:

Wny do you hate the V8s so much? V8>V6 in MANY ways.

 

[progress4m]

In my case the sweet spot is around 65 -70 MPH. I get around 18-19 (calculated) average in 50% city and 50 % hwy with every day driving. This is with lift and AT tires.
When we went on our family vacation last year (From Texas to Colorado to Yellowstone back to Colorado and back to Texas) I got 21.6 mpg (calculated) . Total trip was around 3600 miles. I was not towing anything, but I was going 85-90 mph (uphill) on some hwys in Wyoming.

 

[charlier180]

I will be towing a 3.5K lb pop up camper, so I'm pretty sure I would average higher in the v8 than the v6. At altitude and mountain passes, the v6 would strain pretty hard. I will keep my v8 thanks very much.

I think you are probably right.

This past weekend I attended an Antique Car Meet in the Finger Lakes Region of upstate New York. My route involved climbing a few hills between 2-3K feet high.
I have to wonder how a V6 would have done pulling my loaded, enclosed car trailer on that trip. Oh wait, I would not have done that since the V6 is not rated for over 5K lbs.

At one rest stop I noticed two Porsches on open car trailers.
When I left the rest stop I was able to see the tow vehicles being used and their drivers. One tow vehicle was a Porsche Cayenne and the other was a 4Runner.
I found it interesting that both drivers gave me a somewhat odd look when I passed them pulling my trailer. Were they wishing they had an enclosed trailer or were they wondering how a 4Runner could pull one? When I glanced in my mirrors I did not see a "V8" badge on the 4Runner so I do have to wonder.

BTW, on my way home from that meet on Sunday I can back through those same hills. This time it was a little more interesting with the Heavy Rain and High, Gusty, Winds. Made me ever so glad I have the dual cam sway control. Driving in those conditions without it would have been dangerous to say the least.

When I got home I came to find out that there were multiple tornado watches along my whole route home and in places those "gusty" winds were a lot higher than I have towed through in the past.

FYI, my calculated mileage for the trip was 9.14 mpg based on three fuel fill ups. Pretty good MPGs considering the hills, wind and load I was towing.

Back on topic....

I have found that my MPG sweet spot with my V8 is around 45-55 mph.
In that range I have seen 20-21 MPG (calculated).

 

[progress4m]

Wny do you hate the V8s so much? V8>V6 in MANY ways.

I agree, replay like that is uncalled for… But I believe it is related to the fact that some people who bought V6 are second guessing themselves by choosing V6 over V8 so they need this type of a self reassurance… Please note I emphasizing on word “some” V6 owners.

 

[Barefoot]

I've done the reset thing on flat ground at various speeds.

The slower I go in 5th, the better mileage it gets. I see 28 on flat land at about 45 MPH.(99 coasting down a steep hill) '07 2WD V-8.

I think that aerodynamics are more of a factor than hitting the sweet spot of engine RPM.

The 4R is an aerodynamic brick, and drag goes up with the square of velocity.

 

[eskimochaos]

I agree, replay like that is uncalled for… But I believe it is related to the fact that some people who bought V6 are second guessing themselves by choosing V6 over V8 so they need this type of a self reassurance… Please note I emphasizing on word “some” V6 owners.

The V8 came straight from a 75k Lexus, the V6 was designed for a 25k Toyota.

Nuff Said.

Back on topic, this guy is talking about highway speeds - not 50mph. It depends too much on terrain. Ive gotten 22 calculated going flat at 74-80.

 

[Thai]

I have searched everywhere for specifics on the 4runner tq/hp curves, and nothing comes up.

Here ya go: http://www.toyota-4runner.org/4th-gen-t4rs/55223-torque-curve-b-w-v6-vs-v8.html

 

[progress4m]

Here ya go: http://www.toyota-4runner.org/4th-gen-t4rs/55223-torque-curve-b-w-v6-vs-v8.html

Very good info and I have seen it before, but this is for pre VVT-i V8…. I wish I can find power torque info for VVT-I V8.

 

[jeober]

I've done the reset thing on flat ground at various speeds.

The slower I go in 5th, the better mileage it gets. I see 28 on flat land at about 45 MPH.(99 coasting down a steep hill) '07 2WD V-8.

I think that aerodynamics are more of a factor than hitting the sweet spot of engine RPM.

The 4R is an aerodynamic brick, and drag goes up with the square of velocity.

Yes, 45mph in 5th should maximize economy, v-6 or v-8. 28mpg is quite do-able (2wd).

Faster mph will exponentially tank your mpg.

 

[Goatdog]

I agree with the "get a Scanguage" post. What a difference it makes when you calibrate it. (and reset per the instructions when you fillup)

 

[72bundy]

I have an 06 v8 AWD limited. Well maintained, 40k miles, I bought it a couple of months ago and have been driving it like an old man the past few fillups, keeping the RPM's below 2000 RPM and the computer says 14.1 MPG. I can barely get 260 miles on a full tank of gas. which is 13MPG. Is this normal?

 

[jayjaytuner]

you should be gettin better than 13mpg, idk pull out your maf sensor and clean it, see if that does any good.

 

[FFRC]

I have a 08 V8 Limited (with 118k miles) and when I fill up the computer says that I have about a 410 mile range. I never get that, my fuel light comes on right around 360 miles. All my driving is on the highway up and down gradual hills so it is hard for me to gauge mpg but if I stick around 75 mph I estimate I am getting 20 mpg. The V8 sounds happiest right around 83 mph.

Recently I have seen a decline in mpg but I am due for a sparkplug change (it will be the first change) and expect that is the culprit.