Octane for '15 5.0

[RevvdMedia]

Amongst reading Ford's literature for the new 5.0, I got thinking about what octane I will plan to run when I get my 5.0. For summertime, of course I want ALL the power, which Ford rated the 5.0 on 93 octane. Ideally, in the summer, I would run what is available to me, only two brands (Husky and Petro Canada), which are 94 octane with up to 10% ethanol...somewhat not ideal. Inversely, I can get 91 octane with no ethanol from Shell (V-power), but I lose a nominal amount of power...theoretically. My location is 2000ft above sea level, and I wonder at that altitude if I really would need 91 octane, or if our slightly thinner air would allow for use of 91 octane with no knock retard.

Then comes winter, when I know there is absolutely no reason to ever press the throttle to the floor in a 400lb/ft RWD sports car, it will NEVER hook up. That being said, I wonder about running 87 octane for the subzero months. I don't like the idea of using crap gas in a great engine like the 5.0, but if it really doesn't NEED it, then should I even bother with premium? My past experience with knocky engines is my old Grand Prix GTP, which would see 4 degrees of knock retard at higher throttle even using 91 octane. I wonder under 1/2 to 3/4 throttle if the 5.0 would have any using 87?

I don't want to sound cheap, but the fact 91 octane costs about 75 cents a gallon more than 87...it will add up, especially remote starting the car in winter, idling, cold engine, etc.

Thoughts?

Sponsored

 

[Todd15Fastback]

I will be running 91/93 octane all year round...same as I have done with all my other Mustangs since 1992.

 

[5.0GT]

Run 91/93 for the best performance. This car was meant to run on it.

 

[Chameleon]

93 only.

 

[Clink]

93 only.

+ 1

 

[EXP Jawa]

I would think that 94 octane, mixed with 10% ethanol, is probably compromised in terms of specific output by the ethanol (since the car won't be able to make use of ethanol's higher octane effect), is probably on par with what you'd get from 91 octane with no ethanol blended in. What you loose due to a couple of octane points is probably equal to what you loose from the ethanol blend.

Honestly, in all practical terms, it isn't going to be a noticeable difference in 99% of situations. For me, just driving to work and the store, etc, I can't see the 1% loss in power by running 87 to be worth the extra $6 per fill up. Sure, if I went to an auto-X or an open track event, different story. But around town, a loss of 4HP isn't going to be a big deal. The car will run just fine (no harm done) on 87, so why pay more when it isn't needed?

 

[xlover]

ill run 93 spring summer fall, and probably winter as well as i will forget to think about putting 89 or 87 in... my current car is 93 year round so im used to it

 

[jeebuspwnz]

I would never put 87 octane in a performance engine with high compression that makes more power on higher octane, because all I'd be doing is robbing power and decreasing fuel economy.

Unfortunately though, I'll be running 91 because that's all I can get.

 

[stilesg57]

Run the best octane you can in a performance motor. Not doing so is a total false economy.

How many miles a year do you drive? Divide that by 20 to get your gallons burned. Multiply that by 0.75 to get your add'l dollars spent to consistently run premium fuel. What's the number? If it's under ~$500 it's worth it. Remember that changing octane requires the ECU to learn the change...by running into knock and then backing out timing. If you're going to keep the car very long, it's worth it to run the best octane you can get consistently. Much easier on your very-expensive-to-replace motor.

 

[fionic]

93 only.

+1

it's REALLY not that much more...

 

[Arabian Mustang]

In here we can get 89oct, 93oct and 95oct,and of course 98oct so the option for me is 98oct LOL

 

[HalfMoon]

In here we can get 89oct, 93oct and 95oct,and of course 98oct so the option for me is 98oct LOL

I think you use the RON method to calculate the octane over there. In that case your 98 is the same as our 93. See below:

USA (AKI/PON) - Europe/Others (RON)

87 = 91
89 = 93
91 = 95
93 = 98

Those numbers are rounded down, but here's a page with the formulas: http://www.pencilgeek.org/2009/05/octane-rating-conversions.html

 

[w3rkn]

Amongst reading Ford's literature for the new 5.0, I got thinking about what octane I will plan to run when I get my 5.0. For summertime, of course I want ALL the power, which Ford rated the 5.0 on 93 octane. Ideally, in the summer, I would run what is available to me, only two brands (Husky and Petro Canada), which are 94 octane with up to 10% ethanol...somewhat not ideal. Inversely, I can get 91 octane with no ethanol from Shell (V-power), but I lose a nominal amount of power...theoretically. My location is 2000ft above sea level, and I wonder at that altitude if I really would need 91 octane, or if our slightly thinner air would allow for use of 91 octane with no knock retard.

Then comes winter, when I know there is absolutely no reason to ever press the throttle to the floor in a 400lb/ft RWD sports car, it will NEVER hook up. That being said, I wonder about running 87 octane for the subzero months. I don't like the idea of using crap gas in a great engine like the 5.0, but if it really doesn't NEED it, then should I even bother with premium? My past experience with knocky engines is my old Grand Prix GTP, which would see 4 degrees of knock retard at higher throttle even using 91 octane. I wonder under 1/2 to 3/4 throttle if the 5.0 would have any using 87?

I don't want to sound cheap, but the fact 91 octane costs about 75 cents a gallon more than 87...it will add up, especially remote starting the car in winter, idling, cold engine, etc.

Thoughts?

Why starve your baby.. relish in the fact you have a monster & feed it..!

 

[Arabian Mustang]

I think you use the RON method to calculate the octane over there. In that case your 98 is the same as our 93. See below:

USA (AKI/PON) - Europe/Others (RON)

87 = 91
89 = 93
91 = 95
93 = 98

Those numbers are rounded down, but here's a page with the formulas: http://www.pencilgeek.org/2009/05/octane-rating-conversions.html

That's true , even when I order custom tunes and different things from the states , It's always noted as 93oct , the only small difference is here they actually refine the fuel more than once before selling it

 

[Brent302]

That's true , even when I order custom tunes and different things from the states , It's always noted as 93oct , the only small difference is here they actually refine the fuel more than once before selling it

How's the gas prices there in Dubai? I've heard it's crazy cheap.

Sponsored