Premium fuel?

i looked on here and google for some results but there isn't much information regarding premium fuel In the 3.5l Atkinson... does this motor benefit or enjoy premium fuel or no?

 

No

 

Welcome. This is a very common topic here and has been discussed many times. Some believe it makes a difference but most with empirical evidence say there is no difference. I am in the "no difference" group. Put in it what makes you happy. Do not believe you will see or feel any discernable difference despite the fuel variety. I have tried several times just out of curiosity to run 4 or 5 tanks through mine. No difference.

 

Not a bit, cold or hot weather, uphill or down, night or day, didn't make a single difference.

 

Octane? Higher octane doesn't impact much except your wallet.

But good gas does make a difference. Buy top tier gas but stick with 87 octane.

 

Nope....but if you can find ethanol free fuel DEFINITELY use it.

 

The octane rating could be better described as "Resistance to Detonation or Pinging"

If an engine is not designed to run on premium fuel (advanced timing) it will not see any performance improvement from premium fuel aside from possibly better additives in premium over regular.

Marketing would have you believe that putting premium fuel (and a fartpipe) in your Civic will make it a Ferrari slayer.

 

It makes about $100 average (depends how far you drive) in your wallet each year. So drive it like it is stolen and he happy with it

 

It burns slower.... all things being equal, if an engine is optimized for 87, it should see a reduction in power for higher octane. Engines have dynamic control systems and try to adjust to whatever is being run in it........ The only thing it can't help is compression ratio since it is fixed. So if your engine is designed for 87, it's best to run 87.

 

I have 3600 miles on my truck, have filled up at costco every single time lol

 

Doesn't the ECU compensate with increased timing (negligible to our butt dynos) with higher octane than originally mapped for?

 

You'll be fine, nearly everymajor brand provides Top Tier fuel.

http://www.toptiergas.com/licensedbrands/

 

Yeah thats why I go to costco, plus it's cheap

 

I've been putting 91 since that's what my T4R takes. Guess I can drop to 87.

 

THIS.

 

87 ethanol free has got me the best mpgs I have ever seen. Getting 21 at 6000ft elevation. I wish it was around more though. I only know one place.

 

Through watching my driving habits and switching to ethanol free, I was able to regain most of my lost MPGs after lifting, oversizing tires and bolting on a bunch of stuff.

 

That's why I qualified with "All things being equal"

Yes, most do compensate. What happens is it burns slower and timing is increased until it sees spark knock. It then backs off. The engine won't feel as peppy at first, but as the timing increases it will improve. Some engines may see improvement, some may not. It's a very complex system that and to be truly optimized you have to take into account, fuel (amount, type, octane, temp, pressure, spray), air (density, temp, pressure, swirl), engine (speed, temp, load, demand), ignition (plugs, temp at ground strap, position, voltage)..... lots of factors to consider.

I'd just follow the manufacturers recommendations.

 

this^


I stick with 87 now, but have experimented for 6 months of two tanks 93, two tanks 87, on and on...
and scrutinized my mpg's...will run some 93 once in a while though for no reason other than just more experiments

I found that
depending on how I am driving that day, and humidity, air temp...etc

some days I benefit from 93 octane as my timing is not retarded from knock sensor, so the better engine management offsets
the lower mpg from using 93 octane...and about one in five tanks of 93 octane I see an overall mpg improvement...though
most times...I get equal or poorer mpg. [usually I am driving like a raped ape to see this improvement vs raped-ape
on 87 octane]

most times (4 of 5 tanks) using 'ole panther piss 87 octane' I get the best mpgs, when air temp, driving style means
even if the knock sensors are at work....the built-in better MPG's (more net energy) of lower octane gas shows
...driving style being 'normal
citizen trying to fit into society'


I know damn well this motor wants to knock on 87 octane, I got the knock TSB done and it quieted it down 100% by changing
how the ecu reacts to the sensors and what and when it retards timing......but the sweet spot for this motor is 91 octane gas really...
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I always run 89 because I noticed with my last tacoma that I was getting slightly better mileage. I average about 18mpg city and 22/23 hwy running 89. Havent put 87 in since I owned it so I'm not sure of the difference - either way its like a dollar extra per tank so whatever doesnt bother me to pay a lil extra