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Gas regular or premium???

That 8 horsepower increase between premium and 87 octane in the 5.0 is less than 2%. The difference in price between the two fuels is around 5%. If the 5.0 and 4.6 are designed for either octane, using premium is costing a few bucks each tankful that might not accomplish anything. I tried premium in my 4.6 for a few thousand miles, no difference in performance or mpg that I could tell so I went back to 87. Your car, your money, your choice.
 
That 8 horsepower increase between premium and 87 octane in the 5.0 is less than 2%. The difference in price between the two fuels is around 5%. If the 5.0 and 4.6 are designed for either octane, using premium is costing a few bucks each tankful that might not accomplish anything. I tried premium in my 4.6 for a few thousand miles, no difference in performance or mpg that I could tell so I went back to 87. Your car, your money, your choice.
I think that if people know that there is a difference of 8 HP (along with some small difference in MPG) between regular and premium fuel on the Tau V8, people can figure out themselves which fuel they want to use. There is no need for additional hyperbole on the subject.
 
Using subjective evaluation terms such as "undetectable" is not helpful. The facts are that the certified HP for the 2013 Genesis 5.0 Tau V8 is that it delivers 421 HP @ 6400 RPM with regular fuel, and 429 HP @ 6400 RPM with premium fuel. Very similar differences exist for other Tau versions and model years. Those are the facts Jack. As I clearly stated, it is up to each person as to whether the extra HP is worth the extra cost of premium, but the extra HP is real.

Never once said otherwise and yes all 8 hp such as in Sear Craftsman lawnmower power are in fact real, no argument there.

The rest of you post is a mix of ancient mythology based on old engine designs and out-of-date consumer information, especially if the manufacturer specifically says it run on either fuel and gets more horsepower with premium.

Lets see, written by Scientific American in 2007 which means all the 2009 Genisis buyers will have ancient outdated cars in less than 2 years according to you.

If you want to argue that the increased HP is not worth the cost of premium fuel, that is fine, but please stick to the published HP numbers for each fuel. Personally, I do not think the extra horsepower is worth the extra cost, which is why I purchased a V6, but some people may think otherwise.

Which is what my post was entirely about until you made it out to something completely different. You would do extremely well and prosper as a lawyer you know. :D

:welcome:
 
OP asked for suggestions on premium vs regular. 5 pages of experiences and opinions and when I post some actual cost/benefit numbers you call it hyperbole. Please explain what you think is exaggerated about my 5% fuel cost vs 2% hp gain.
 
OP asked for suggestions on premium vs regular. 5 pages of experiences and opinions and when I post some actual cost/benefit numbers you call it hyperbole. Please explain what you think is exaggerated about my 5% fuel cost vs 2% hp gain.
You don't need to repeat numbers that I already posted (8 HP difference for 2012). I also don't think you need to post information about the difference in price between regular and premium, as most people are smart enough to figure that out also (which varies by location anyway). And finally, you may be surprised, but most on this forum can do the math.

But to answer your question, there is no direct relationship between percent increase in fuel cost and percent increase in HP, or any of the other things that people spend their money on to enhance their Genesis.

Lastly, the question of increased fuel mileage (MPG) is missing from the equation. If an engine gets 421 HP @ 6400 RPM with regular fuel, and 429 HP @ 6400 RPM with premium fuel, that means that with premium fuel the engine needs less fuel to get to the same HP. I am not trying to say whether the extra MPG when using premium is worth the extra cost of premium gas, but it should be part of the equation if one wants to get technical.

Just to clarify, an older engine that is designed to run only at a particular octane level only will not see a benefit in MPG when using higher octane fuel, but the Tau V8 is designed to take advantage of premium and will see at least some MPG improvement compared to regular gas, which is why premium fuel was used for EPA certification of MPG.
 
But to answer your question, there is no direct relationship between percent increase in fuel cost and percent increase in HP, or any of the other things that people spend their money on to enhance their Genesis.

Lastly, the question of increased fuel mileage (MPG) is missing from the equation. If an engine gets 421 HP @ 6400 RPM with regular fuel, and 429 HP @ 6400 RPM with premium fuel, that means that with premium fuel the engine needs less fuel to get to the same HP. I am not trying to say whether the extra MPG when using premium is worth the extra cost of premium gas, but it should be part of the equation if one wants to get technical.

Just to clarify, an older engine that is designed to run only at a particular octane level only will not see a benefit in MPG when using higher octane fuel, but the Tau V8 is designed to take advantage of premium and will see at least some MPG improvement compared to regular gas, which is why premium fuel was used for EPA certification of MPG.

If im driving at 6400 rpm mpg is the least of my worries. The problem with variable build quality and variable results on a dyno will have a variance +- 5% or so. That being said id like to see the dyno chart before saying wooohooo. Though still i stand by my thoughts 4000 lb car ... 4500 with wife a few hp for the cost of premium doesnt compute


Ppp
 
No way I'd use anything less than premium on a brand new time-unproven GDI engine.
 
Is this question any different than someone who owns a high quality home with a really upscale, super-efficient HVAC system, but wonders if they should use a cheap $6 filter or a high-quality one that meets better specs and costs a few dollars more?

I don't think so, because they both work, and many people -- not all -- believe that quality and performance intrinsically warrants the use of/investment in fuels, parts, etc. that also have optimum quality and performance.

These cars most likely don't really care. But the owners do. I'll continue to use too-tier only, alternating between 89 and 93, and as often as I can find it and avoid arrest by the corn-Nazis, I'll use non-ethanol.

It's only money and its only a car.
 
<snip>
I'll continue to use too-tier only, alternating between 89 and 93, and as often as I can find it and avoid arrest by the corn-Nazis, I'll use non-ethanol.

It's only money and its only a car.

Just be happy that you can even find non-ethanol petrol. I can't find any places in Austin that are (which is odd, considering Texas is the home of big-oil in the US).
 
Is this question any different than someone who owns a high quality home with a really upscale, super-efficient HVAC system, but wonders if they should use a cheap $6 filter or a high-quality one that meets better specs and costs a few dollars more?

It's only money and its only a car.

Interesting thing with the HVAC system... i had mine replaced a few years ago and had the filter replaced with a 4" paper filter. Basically they make different grades of filters that will filter down to smaller microns. If you have allergies then you would want the highest filteration rate filter possible... though the performance of the blower would be reduced = more money but better health. using a filter that isnt as strict would result in more airflow and less $$$ spent (on filter and energy). I think they call it the merv griffin rating or something ;)

They both work and its based upon user needs.

ppp
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Interesting thing with the HVAC system... i had mine replaced a few years ago and had the filter replaced with a 4" paper filter. Basically they make different grades of filters that will filter down to smaller microns. If you have allergies then you would want the highest filteration rate filter possible... though the performance of the blower would be reduced = more money but better health. using a filter that isnt as strict would result in more airflow and less $$$ spent (on filter and energy). I think they call it the merv griffin rating or something ;)

They both work and its based upon user needs.

ppp
A well-designed HVAC system will provide increased filter surface area to compensate for using low allergen filter types that restrict airflow. This can be done by having multiple air returns, spec'ing a larger filter for a single air return, or both.
 
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Just be happy that you can even find non-ethanol petrol. I can't find any places in Austin that are (which is odd, considering Texas is the home of big-oil in the US).
Ethanol is mandated for air pollution reasons (aside from the political pressure applied by corn growing states). You are not going to find it in a many large metropolitan areas, and is supposedly only to be used by engines that can't handle ethanol (not just for automobile engines).
 
Speaking generally, I get a kick out of some people who will buy a nice new car, keep it clean, possibly modifie the engine for better performance or talk about getting the best mileage they can get - and yet, run the cheapest crap gas because they assume it doesn't matter. I grew up on the rule of thumb that for any car you care about, you run premium. It costs more at the pump, but you get better mileage, performance, longevity, peace of mind, etc, etc. If you think the differences in gas are just "marketing", why then would you ever bother to wash and wax or change the oil in a car?? Low octane cheap gas is for people who truly don't care about their engine.
 
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The 3.8 doesn't require premium nor is it recommended. There are no claims by the manufacturer of better mileage or longer engine life using premium. I don't see any reason to use it.
 
There are many reasons, detailed in this and several other threads, and across many forums like this one. Minimum standards are possibly good enough, depending on the brand you run, to get you down the road unawares, but don't you want the best for your car?? Do you wash it? Wax it? Why would you bother with all that, or your "premium tech" package and lighted door sills, since none of it is specifically recommended in the manual?? In short, why put so much love into your car and then say there's no reason to put decent gas in it?
 
Speaking generally, I get a kick out of some people who will buy a nice new car, keep it clean, possibly modifie the engine for better performance or talk about getting the best mileage they can get - and yet, run the cheapest crap gas because they assume it doesn't matter. I grew up on the rule of thumb that for any car you care about, you run premium. It costs more at the pump, but you get better mileage, performance, longevity, peace of mind, etc, etc. If you think the differences in gas are just "marketing", why then would you ever bother to wash and wax or change the oil in a car?? Low octane cheap gas is for people who truly don't care about their engine.

Your problem is you associate price with quality which is not the case at all. You talk about marketing however the only person who is getting taken is you as you also associate the word "Premium" as being the best. Premium has no benefits at all in cleaning power or increased HP or anything else for that matter. All it does is increase octane which in turn makes the gas less volatile and therefor will not prematurely ignite and cause pinging. Todays cars however with all the knock sensors and electronic stuff on board adjust for this so even premium recommended cars usually all run perfectly normal on regular fuel except some of the turbo variety which can be a little finicky. I drove my Nissan Murano (Premium fuel) on regular for the 5 years I owned and the same with my Acura TL Type S with no ill effects or noticeable difference. Even my Rspec uses regular simply because I cannot for the life of me notice 7 extra hp when premium is used and if anybody can notice this measly amount considering you have more than 400+ already you must be blessed with super powers. Why would I throw 5-6 dollars out the window every time I fill up? Using premium in a car which recommends regular result in less efficiency and a slight decrease in performance. No matter I say I will not convince you because you were brought up that way however this is false information.

I encourage you to continue to use premium in all your vehicles and and yard equipment as this keeps the prices down for us brainless common folk who know nothing about gasoline.
 
Your problem is you associate price with quality which is not the case at all. You talk about marketing however the only person who is getting taken is you as you also associate the word "Premium" as being the best. Premium has no benefits at all in cleaning power or increased HP or anything else for that matter. All it does is increase octane which in turn makes the gas less volatile and therefor will not prematurely ignite and cause pinging. Todays cars however with all the knock sensors and electronic stuff on board adjust for this so even premium recommended cars usually all run perfectly normal on regular fuel except some of the turbo variety which can be a little finicky. I drove my Nissan Murano (Premium fuel) on regular for the 5 years I owned and the same with my Acura TL Type S with no ill effects or noticeable difference. Even my Rspec uses regular simply because I cannot for the life of me notice 7 extra hp when premium is used and if anybody can notice this measly amount considering you have more than 400+ already you must be blessed with super powers. Why would I throw 5-6 dollars out the window every time I fill up? Using premium in a car which recommends regular result in less efficiency and a slight decrease in performance. No matter I say I will not convince you because you were brought up that way however this is false information.

I encourage you to continue to use premium in all your vehicles and and yard equipment as this keeps the prices down for us brainless common folk who know nothing about gasoline.
First you say there is no extra HP, and then you admit that there is 7 more HP with premium gas. Just because you don't notice it, doesn't mean the extra HP is not there.

A lot of people don't notice any difference in normal driving between the 3.8L and 5.0L engines, especially since the 5.0 is about 200 lbs heavier.
 
First you say there is no extra HP, and then you admit that there is 7 more HP with premium gas. Just because you don't notice it, doesn't mean the extra HP is not there.

A lot of people don't notice any difference in normal driving between the 3.8L and 5.0L engines, especially since the 5.0 is about 200 lbs heavier.

The Genesis is rather special as it is designed to operate on both fuels. It is also one of maybe a handful on the market where they recommend both types to be used. If the car is not specifically designed to use premium and you do use it then there are no added benefits.

Are you saying you are willing to pay 5-6 dollars every fill up for something that is not detectable but it says on paper it is there?

Read this, may help enlighten some. http://www.consumerreports.org/cro/2012/01/paying-for-premium-gas-can-be-a-waste-of-money/index.htm
 
The Genesis is rather special as it is designed to operate on both fuels. It is also one of maybe a handful on the market where they recommend both types to be used. If the car is not specifically designed to use premium and you do use it then there are no added benefits.

Are you saying you are willing to pay 5-6 dollars every fill up for something that is not detectable but it says on paper it is there?

Read this, may help enlighten some. http://www.consumerreports.org/cro/2012/01/paying-for-premium-gas-can-be-a-waste-of-money/index.htm
I read it (and many others like it). Most of that info is outdated (to due technology enhancements) or only applies to "some" new engines.

I have the 3.8L V6, and I would not pay more for the 5.0L, either purchase price or lower gas mileage. I am not saying one way or the other whether one can notice the difference in HP (especially if you already have over 400 HP), but I don't believe it is correct to say that there is no difference in HP, and websites who claim that for all new cars are often incorrect.

I have tried mid-grade in my V6 and did measure about 1 MPG improvement compared to regular. That doesn't mean I will still use it, but it was an interesting experiment.
 
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