Premium Gas or Mid Grade??

Well, I can't leave this thread without asking all you peeps that don't want to use premium in your "premium recommended" cars.......... How much do you spend a month on bottled water??????? :D
 
webby said:
I don't see the 10hp/10tq happening without tuning the car specifically for premium, but thanks for the link.
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Let me say this about that. I also own an "old school" Miata - no variable valve timing - nothing fancy, just a straight forward car. Add four degrees timing advance and premium fuel and it transforms the car-pulls harder and gets to the redline faster...just sayin' is all...
 
That's with adding timing...so I have no problem believing that.
 
Thought you were referring to an equivalent to flashpro and adjusting things by 4 degrees in the miata.
 
By oldschool , I guess he is referring to turning the distributor to advance the timing. In regards to the people who post about cost , in my situation it has nothing to do with cost. I am a fse and I get my gas paid by my company. They also give me a car allowance for using my personal vehicle to get to the different sites that I have to service , cheaper for the company. They supply a gas card in which regular gas can be bought. I will try to talk to them and explain that my vehicle requires premium but I am unsure of what the outcome will be. The thing is I really want an SI as I like to enjoy my drive to work. To be honest I feel like the stig sometimes and drive the **** out of my cars. Hey if you have to drive alot , why not enjoy it?.
 
Did you read through the thread?. There are so many different factors at play here. First he is modded , second he did this test one year apart with 20,000+ miles added onto his engine which brought him over the 110k mark , third is the calibration of the dyno and if it was maintained properly or not. Any car thats modded and probably abused will probably lose whp with those factors. I'm not saying hell yeah premium gives hp , but it did advance his engine timing , which goes to show it does make somewhat of a difference maybe not in hp but in the fact that the ecu advanced the timing due to the premium. Like Webby mentioned with added timing...
this was taken from one of the op's posts after everyone chimed in , "You know I agree that theoretically the J30A4 should get more power with 93, that's why I used it for 8 months. All the calculations prove it, the theory proves it, the Honda guy proves it, and the 1/4 mile times prove it. Maybe something really screwy happened here". Just saying...
 
njhustler said:
Did you read through the thread?. There are so many different factors at play here. First he is modded , second he did this test one year apart with 20,000+ miles added onto his engine which brought him over the 110k mark , third is the calibration of the dyno and if it was maintained properly or not. Any car thats modded and probably abused will probably lose whp with those factors. I'm not saying hell yeah premium gives hp , but it did advance his engine timing , which goes to show it does make somewhat of a difference maybe not in hp but in the fact that the ecu advanced the timing due to the premium. Like Webby mentioned with added timing...
this was taken from one of the op's posts after everyone chimed in , "You know I agree that theoretically the J30A4 should get more power with 93, that's why I used it for 8 months. All the calculations prove it, the theory proves it, the Honda guy proves it, and the 1/4 mile times prove it. Maybe something really screwy happened here". Just saying...
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So you don't find it compelling that even after all those factors the dyno chart still looks virtually exactly the same (not just peak tq and HP, but the entire graph!)? If other changes happened in his engine that caused alterations to performance either positive or negative, I find it extremely unlikely that the dyno chart would look virtually identical. If it were making less power after those 20k+ miles, then I would say you have a point, but 110k miles is nothing to a Honda engine. The fact that he gave it a year makes the argument stronger since the ECU had plenty of time to fully adjust to the higher octane and driving style, etc. and after all that time there was no change. He would have to absolutely abuse his engine a TON for him to have power-losing engine damage. Just because he is modded does not mean he even abuses it so you are making an assumption. It is extremely unlikely if not impossible that engine damage or wear would cancel out exactly 100% of the gains (not more or less) from using 93 octane and that the dyno chart would look exactly the same.

1/4 mile times are subjective unless someone literally drove exactly the same in exactly the same conditions except for switching 93 octane.... there are too many factors in track conditions and driving ability among different people and even with the same person over time. Someone could get a crappy time on the first trip to the strip, and then come back with 93 octane and simply drive better. This would create the illusion that the 93 octane helped when in actuality the driver probably shifted quicker, or got a better launch. At least with the dyno the conditions are more stable.
 
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At the end of the day, the ECU may be able to advance the timing, but you cannot change the compression ratio without engine work. You can dial it back, but you can't turn it up. There's nothing in higher octane gas that increases the hydrocarbon content or oxygen content in your cylinders. It's a myth. Physics busts it all day long. The Honda engine engineer should know this, which means he probably meant something else, or something was lost in translation.

All those dyno runs and lap times can change from many different factors. Correlation /= Causation.

If the car says to run 87, you're simply throwing away $$$ running 93. If the car says 93 and you run 87, your ECU can compensate for the detonation by dialing back the engine performance.
 
Dumb thread is dumb!

*Motion to lock this thread :giggle: *

**** up your engine! Go ahead. Don't bring it into Honda if you have issues! :mad:

Quit being cheap asses and put what they require in there for ***** sake! Ugh
 
Just to add gas on the fire (regardless of grade) I added 89 instead of 87 into my 2.0 Mazda 3 and the difference is notable. I would not add 91 or 94 in it since it would be a waste but 89 runs smoother and acceleration is smoother as well. Car requires 87 by manual.
 
Dragos said:
Just to add gas on the fire (regardless of grade) I added 89 instead of 87 into my 2.0 Mazda 3 and the difference is notable. I would not add 91 or 94 in it since it would be a waste but 89 runs smoother and acceleration is smoother as well. Car requires 87 by manual.
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I need proof. lol :rotfl:
 
hotshot said:
At the end of the day, the ECU may be able to advance the timing, but you cannot change the compression ratio without engine work. You can dial it back, but you can't turn it up. There's nothing in higher octane gas that increases the hydrocarbon content or oxygen content in your cylinders. It's a myth. Physics busts it all day long. The Honda engine engineer should know this, which means he probably meant something else, or something was lost in translation.

All those dyno runs and lap times can change from many different factors. Correlation /= Causation.

If the car says to run 87, you're simply throwing away $$$ running 93. If the car says 93 and you run 87, your ECU can compensate for the detonation by dialing back the engine performance.
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The car can tune it to run better when you run a higher octane fuel though a good example of this is in the manual of the Honda Pilot which normally runs 87 octane fuel but recommends you to increase the octane to 91 when towing a trailer over 3500 lbs.

Fuel recommendation: Unleaded gasoline with a pump octane number 87 or
higher required
Fuel tank capacity: 21 US gal (79.5 L)

• When towing more than 3,500lbs (1,590 kg), use of gasoline with a pump octane
number of 91 or higher is recommended.

Cant see any reason they would recommend increasing octane number other than for additional power in this case.
 
Legendarydust said:
The car can tune it to run better when you run a higher octane fuel though a good example of this is in the manual of the Honda Pilot which normally runs 87 octane fuel but recommends you to increase the octane to 91 when towing a trailer over 3500 lbs.

Fuel recommendation: Unleaded gasoline with a pump octane number 87 or
higher required
Fuel tank capacity: 21 US gal (79.5 L)

• When towing more than 3,500lbs (1,590 kg), use of gasoline with a pump octane
number of 91 or higher is recommended.

Cant see any reason they would recommend increasing octane number other than for additional power in this case.
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How 'bout to stop incessant pinging that even the ECU can't handle under certain situations - such as heavy loads.
 
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