interesting video reg vs premium

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Interesting video of a vw gti 2.0t turbo running regular vs premium. Running regular they dyno'd and had 236hp running premium 241 hp. Dont really thinlk you would notice 5hp. For those of you on the fence this is a strong argument for regular, I would just buy it from a good source. I have run it in my 2018 A4 for 20k and 2018 Q5 for 18 k miles. Before had a 2007 A6 3.2 with 12.5 :1 compression which ran on regular for 150k miles without issue. And that is extremely high compression ratio in that engine. Just wanted to pass some factual info.... https://www.youtube.com/watch?v=d8L-X89duEs
 
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Isn't Britain's low octane gas equivalent to a 90 octane in the USA? So this across the pond might not be valid here.
 

pbm

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Last week I filled up in NJ and regular was $1.89 a gallon while premium was $2.79 a gallon....I'd take the 5hp hit at that price differential....
 
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The numbers are not equivalent between the UK and the USA. Britain uses the RON test to rate octane and in the USA the octane rating on the pump is calculated as (RON+MON)/2. 92 octane in the UK is more or less equivalent to 88.5 octane in the US. 95 octane is equivalent to 91 octane in the US.
 
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I'm a little surprised that the power loss is not a little more, I would of expected a 10 or 15 hp loss with regular. But with a modern fuel injected computer control car they're very good a adjusting the timing a touch to compensate for the higher volatility of regular gasoline. I know a few people that drive a cars designed for premium and generally only use regular and don't really notice the difference, I think even if you lost 10hp off a 240hp engine you'd be hard pressed to feel it in the old butt dyno.
 
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Originally Posted by ripcord
The numbers are not equivalent between the UK and the USA. Britain uses the RON test to rate octane and in the USA the octane rating on the pump is calculated as (RON+MON)/2. ...
The advertised octane numbers were RON in the US too, until the government mandated posting (RON+MON)/2, on the grounds that that average better correlates with real-world tendency to knock.
 
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Originally Posted by Skippy722
Just run what is recommended in your owners manual.
Agreed, and I would add that if you drive a vehicle where premium is "recommended" just use it...the price difference here is about $0.30 per gallon and you typically get better detergents and less (or no) ethanol.
 
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check out goapr.com for real results torque 223 stock tuned with 93 oct 341!!! hp 221 stock 278 tuned!! todays DI engines leave a LOT on the table!!
 
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Originally Posted by tbm5690
Originally Posted by Skippy722
Just run what is recommended in your owners manual.
Agreed, and I would add that if you drive a vehicle where premium is "recommended" just use it...the price difference here is about $0.30 per gallon and you typically get better detergents and less (or no) ethanol.
The difference here can be close to $0.90 Per gallon and as Ethanol BOOSTS octane ...I bet on average you get more of it in premium gasoline. And how can anyone know that there is "better" detergents in premium gasoline.
 
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Originally Posted by ammolab
Originally Posted by tbm5690
Originally Posted by Skippy722
Just run what is recommended in your owners manual.
Agreed, and I would add that if you drive a vehicle where premium is "recommended" just use it...the price difference here is about $0.30 per gallon and you typically get better detergents and less (or no) ethanol.
The difference here can be close to $0.90 Per gallon and as Ethanol BOOSTS octane ...I bet on average you get more of it in premium gasoline. And how can anyone know that there is "better" detergents in premium gasoline.
It's a 50 to 60 cent spread here between 87 and 93. At current prices, it's ~$30 to fill up with 87 assuming 15 gallons, and ~$37 to fill up with 93. That being said, I use 89 (recommended) in my ram even though it would run just fine on 87 per the manual.
 
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Originally Posted by ammolab
Originally Posted by tbm5690
Originally Posted by Skippy722
Just run what is recommended in your owners manual.
Agreed, and I would add that if you drive a vehicle where premium is "recommended" just use it...the price difference here is about $0.30 per gallon and you typically get better detergents and less (or no) ethanol.
The difference here can be close to $0.90 Per gallon and as Ethanol BOOSTS octane ...I bet on average you get more of it in premium gasoline. And how can anyone know that there is "better" detergents in premium gasoline.
The premium here (91) is ethanol-free as opposed to most of the 87 being E-10.
 

JHZR2

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Originally Posted by pbm
Last week I filled up in NJ and regular was $1.89 a gallon while premium was $2.79 a gallon....I'd take the 5hp hit at that price differential....
The last number of years premium price premiums have gone out of whack from their traditional norms. The one thing to determine is if it's just HP, or economy too. My Saab was rated for premium, but could use both, and the fuel economy was favorable with premium.
 
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In the 3 years I've had my GTI (2.0T) I've never run 87 in it. During the winter I'll run 89 and summer 93. How much extra power it delivers who knows, but it does feel slightly smoother. That and I do see a little bit better fuel economy. On my backroads commute I average 35-37mpg depending on how frisky I feel like driving. The cost difference is minimal as the fuel tank is pretty small. We also do not have many top-tier fuel stations in my area and the ones that are around are too far out of the way for me.
 
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Originally Posted by raaizin
Interesting video of a vw gti 2.0t turbo running regular vs premium. Running regular they dyno'd and had 236hp running premium 241 hp. Dont really thinlk you would notice 5hp.
2% is probably within margin or error of the dynamometer, don't you think?
 
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I don't like the uneven acceleration of running on the knock sensor with regular fuel, as it keeps pulling timing as it constantly senses knock.
 
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Originally Posted by Skippy722
Just run what is recommended in your owners manual.
Wrong; it's always better to second-guess the engineers- what do they know? All they did was design the engine.
 
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At the risk of being "octane shamed" I'll reveal I just filled up my regular specificied 2013 Silverado 5.3 with premium. It was only 11 cents more a gallon, and for less than 3 bucks, I want to see if there is a performance or mileage difference on a long trip that I regularly make.
 
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I don't use premium to achieve maximum hp. 252hp vs 241hp in the Focus isn't perceptible using a butt dyno. I use it so the knock sensor never / rarely has to intervene. Knock is akin to striking the top of your pistons with a hammer...something I like to avoid. Something my Canyon has taught me from day one is that just because a car only requires 87 doesn't mean it won't knock with it. I listened to it knock for a week before switching to 89, then got the TSB done to stop the transmission from allowing 1100 rpm driving in 6th gear. Took a slight MPG hit, but purrs like a kitten. Mustang and Focus get 93 and SN Plus oils, and never lug the engines. Not even giving them a chance to knock, or experience LSPI.
 
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Originally Posted by MCompact
Originally Posted by Skippy722
Just run what is recommended in your owners manual.
Wrong; it's always better to second-guess the engineers- what do they know? All they did was design the engine.
And yet there seems to be evidence that bean counters run the company (and write the manuals). I have yet to run premium in anything I own. But I do believe in repeatable data. If a few tanks of fuel offer smoother running, measurably faster acceleration, or better mpg, then premium may be required. However, only if cost per mile also becomes better is it a slam-dunk on running premium: all of the prior measurements may be true, but if the additional cost of running premium outweighs higher mpg, then it may not be worth it. And of course, if nothing improves on premium then it's of no use. YMMV.
 
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