Regular vs premium fuel?

[maverick1]

I'm still driving on the first tank of fuel the dealer put in my car.
I asked the salesman if he could fill it up with premium but the dealer policy is to put regular in all cars.
My question is, will I feel a difference in performance going from regular to premium fuel?

 

[jdubs]

Yes. The car adjusts based on octane. Regular won't hurt anything, but max performance is achieved with premium.

 

[maverick1]

Great. Something to look forward to on my next fill up.

 

[DoucheBagGold]

I thought the owners manual said to use 87 octane?

I just got the car yesterday and need to look through it better though.

 

[dyn085]

I thought the owners manual said to use 87 octane?

I just got the car yesterday and need to look through it better though.

The new ECU's can compensate for octane through the use of their Octane Adjustment Ratio.

 

[Capri to ST]

I thought the owners manual said to use 87 octane?

I just got the car yesterday and need to look through it better though.

it's a bit confusing, because it does say that (87 recommended) in one place in the ST Supplement, but when it shows the maximum HP and torque numbers in another place in that same manual, it notes that those figures are achieved with 93 octane, so it is as jdubs says above.

 

[me32]

For best performance use 91+. If you choose to save money on gas the car runs fine on 87.

 

[TyphoonFiST]

Just use premium 91 Oct to 93 oct. ...if you bought this car to be an economy car.....go trade it in and get a regular fiesta. Don't deny this car it's true potential to save yourself a couple of dollars at the pump. Let the car shine....it gives you a smile on your face when you drive it right? Why not give it the best so it can perform at its top notch capability?

 

[John9851]

I agree use the 93 octane the car responds to it also my mpg went up to 31

 

[DoucheBagGold]

Ok no problem. I'm coming out of an Audi so I'm used to paying for premium fuel already so no big deal to me.

I just wanted to make sure I wasn't going to be wasting money on premium fuel if regular is all that is needed but I did buy this because I wanted something more sporty and fun so I'll be filling with premium as soon as this first tank runs out.

 

[DoucheBagGold]

Does anyone have the hp ratings based on the different octanes or just how much difference is there between 87 and 93?

 

[Brickell FIST]

I couldn't get a meaningful difference in timed runs from 40-80 mph on a race logic. We are talking .1 or .2...That was a third gear pull no shifting. I'm sure there is some measurable difference someplace. Not in that pull. Most people fall victim to the placebo effects of the butt dyno.

 

[Joker328]

Probably not much of a meaningful difference on a stock tune. However, if you plan on tuning, even the off-the-shelf tunes require 91 or 93 and they do noticeably improve performance.

 

[Brickell FIST]

Joker, thanks for pointing that out. That is a big difference.

 

[OffTheWall503]

My dealer also put in a tank of regular 87 I suspect, so I tried to run it out as quickly as possible and put in 92 octane immediately after and from there on. Stick with the highest octane available at your local stations or when going on a trip.