Filling up - 87 vs. 89

[S1njin]

The 86/93 thread started to drift somewhat (because of me), so I thought I'd target my specific question in its own post.

I'm not likely to ever tow 5000 pounds of anything, ever. I bought this truck for its targeted purpose; commuter, family hauler, HD/Lowes/ACE/Landscaping picker uper.

I read a lot about CISMOs open loop/closed loop (apologize if I spelled his name wrong). I keep reading about how Gary said somewhere that 90 was the sweet spot for this engine.

So ... am I/are we wasting $$ by putting 89 in the truck if not towing 5000 pounds? I have my first fill up today .... wanna get it right !

[Ian Brantford]

The Search tool is your friend. There is already a thread on this very subject this month:

http://www.ridgelineownersclub.com/f...ad.php?t=46393

I recommend following up there instead of here.

[bamf3000]

I'm sure the higher octane gas could help with horsepower if the car is adjusting timing based on the octane rating, which would create a hotter burn, but I doubt it would do anything for gas mileage.

Reading through all the treads. Everything that has been posted about 90 octane rating from Gary flint has been He said, she said. I do not believe we have seen anything from him stating it provided better gas mileage.

[speedlever]

Originally Posted by Ian Brantford

The Search tool is your friend. There is already a thread on this very subject this month:

http://www.ridgelineownersclub.com/f...ad.php?t=46393

I recommend following up there instead of here.

That thread will be months in the making as I fuel and observe the results. I decided to run the test as numerous anecdotal reports were made about the mpg benefit of using higher octane fuel so I wanted to see if it would make a difference in my world.

After two fuelings with each vehicle, the results are neither impressive nor conclusive.

But it seemed to take a while before my non-ethanol test began to show results too. I ran that test for 7 months. The RL seemed to benefit but the Pilot did not. Go figure.

S1njin, you won't go wrong as long as you use 87 minimum octane. Don't sweat it. Fill it with 87 and be happy. Your driving environment will be unique to you. Thus, you may or may not benefit from higher octane. I am simply running a test (until I decide to quit) to see if my vehicles benefit any from running 89 octane over a period of time.

Your RL won't know the difference from a quality perspective as long as you use a station that maintains its supply properly and turns the fuel over pretty rapidly.

If you decide at some point to test 89 octane to see if you get better mpgs, then you will have a history to with which to compare. Do as many of us and document your fueling on Fuelly. You can click my siggy for a link to the Fuelly site and set up your own. Hover your cursor over the notes and you can see what I post for each fueling.

[S1njin]

Originally Posted by speedlever

That thread will be months in the making as I fuel and observe the results. I decided to run the test as numerous anecdotal reports were made about the mpg benefit of using higher octane fuel so I wanted to see if it would make a difference in my world.

After two fuelings with each vehicle, the results are neither impressive nor conclusive.

But it seemed to take a while before my non-ethanol test began to show results too. I ran that test for 7 months. The RL seemed to benefit but the Pilot did not. Go figure.

S1njin, you won't go wrong as long as you use 87 minimum octane. Don't sweat it. Fill it with 87 and be happy. Your driving environment will be unique to you. Thus, you may or may not benefit from higher octane. I am simply running a test (until I decide to quit) to see if my vehicles benefit any from running 89 octane over a period of time.

Your RL won't know the difference from a quality perspective as long as you use a station that maintains its supply properly and turns the fuel over pretty rapidly.

If you decide at some point to test 89 octane to see if you get better mpgs, then you will have a history to with which to compare. Do as many of us and document your fueling on Fuelly. You can click my siggy for a link to the Fuelly site and set up your own. Hover your cursor over the notes and you can see what I post for each fueling.

I only use Shell or Exxon S they are the only Top Tier gas stations around. Thanks for the advice - I put 89 in the truck today but it was a 45 cent premium !

[speedlever]

IMHO, 89 is not worth that price diff. I've been paying a 17 cent premium for Shell 89 and I almost choke on that.

[rollinhonda]

We pay a lot for gas in CA, but the differences of 10c between octane levels are fairly standard, as an average anyway. Some will blow up the top premium another 12-15c over 89, but even that seems rare in my experience. We have a few 92 octane stations, but most are consistently 87-89-91.

[speedlever]

Regarding using "premium" fuel, here are a couple of posts by Kodiak:

http://www.ridgelineownersclub.com/f...47&postcount=3
10hp is instant when you buy premium That should be your first upgrade. Avoid ethanol if you care about FE. It will increase the octane -
but reduces the BTU content in the fuel.

http://www.ridgelineownersclub.com/f...39&postcount=9
The engine ECU constantly monitors the fuel and thousands of other environmental parameters to optimize the power possible given the operating conditions and fuel. The ECU does in fact have the logic to optimize the power based on the fuel. The 10hp is real. Why do you think it is strongly recommended when towing? That is what it takes to achieve the necessary operation in extreme heat and load conditions. It is not a myth it is fact.

Sounds to me like HP is addressed, but mpg is not.

[Ourfarm09]

It's pretty much a fact, more horse power = less miles per gallon.

[MikeT]

Originally Posted by Ourfarm09

It's pretty much a fact, more horse power = less miles per gallon.

Not necessarily.