Does premium gas make a big difference over regular?

[2BullittS]

Why bother with regular? It’s a performance car and the yearly cost isn’t that much more between the two. I want max performance when I want it.

Sponsored

 

[Nagare]

I have 18" Firestone Firehawk Indy 500 tires speed rated at 168mph.

So, if I get the Ford performance tune (100hp engine bump with upgraded air intake) and use 93 octane gas will I get 148mph, I should...correct?

Terry

M-9603-M4 is the part number and you're not going to see 100hp across the board, that's just where it was anemic on the top end before. Hard to find much on whether it removes the limiter or not, might be a question you want to ask Ford Performance. This post makes it seem like it is removed, but that's only one post.

 

[Nagare]

The drive shaft balancing is also a reason Ford limits speed. There were some problems a few years back with drive shafts exploding at high speeds.

AFAIK that wasn't an issue on the S550s, that's S197 V6 cars.

 

[Bullitt0819]

Actually they test on 91, not 93. Out west in the rockies and in commiefornia they can only get 91 so they test using that octane.

I live in 'commiefornia.' There is a station selling 100-octane racing gas about a mile from my house.

 

[Intrepid175]

I've got a 2016 GT. I've run multiple tanks of regular and premium. I'm not one who pushes the car hard enough for premium to make that much of a difference most of the time but I do tend to think it that by the butt dyno, the premium is helping. The other thing I think I notice is, the engine runs a little smoother just tooling around. Not that it's bad on regular, it just feels happier on the whole with premium.

 

[Deleted member 35786]

I've got a 2016 GT. I've run multiple tanks of regular and premium. I'm not one who pushes the car hard enough for premium to make that much of a difference most of the time but I do tend to think it that by the butt dyno, the premium is helping. The other thing I think I notice is, the engine runs a little smoother just tooling around. Not that it's bad on regular, it just feels happier on the whole with premium.

LOL Definitely butt dyno..

 

[ChiTownStang26]

Youd be amazed to see how much a stock untuned coyote knocks without Premium gas. Hooked up my x4 and set it up to watch the knock sensor and all it did was knock. It would be +2 knock constantly on the highway. Put 93 in next tank and the knock sensors would read negative all the time. Dont know about the eco but the coyote will knock without Premium.

Your speed limit is limited from the base tune on the car like others said, has nothing to do with octane.

 

[Ebm]

Premium gas only makes a difference, horsepower wise, on the ecoboost. Running an ecoboost on regular gas makes the car lethargic. The GT gains a whopping 5-7 horsepower running premium gas versus regular gas. So not much of a difference at all.

The only reason I run premium gas(93) is to have a safety net for oil contamination. Otherwise, there is nothing wrong with running regular 'ole 87 octane in your GT.
*Cue the muscle heads to come in and tell me if you run regular octane gas, your car will explode lol. No it won't, a GT runs just fine on regular gas...

 

[tcman54]

Arrg, my head is about to explode...

My 2016 Ecoboost, feels extremely quick off the line and all the way up to the low 120's mph on regular gas, I have no problems about how the car feels.

But it bugs me that I can't get the car over 126mph, I have tried to pass a few cars and got shown up, the car simple won't go pass this top speed regardless of tires or gas.

So it appears that the only way to get above 126mph is to get a tune that will take the limiter off of the engine program.

It seems silly to me that Ford markets a sporty car, lists the top end at 148mph and then limits the car to about 125mph....because they don't want people to out drive the crappy stock tires.

Terry

 

[Deleted member 35786]

Youd be amazed to see how much a stock untuned coyote knocks without Premium gas. .

Wrong..... There is no data to support your claim. If that was the case Ford would require premium gas and not just recommend it. It may knock under heavy loads at altitude or pulling a trailer perhaps.. but for daily use.. not. If it does then you have an engine issue or bad gas.

 

[Bikeman315]

I have 18" Firestone Firehawk Indy 500 tires speed rated at 168mph.

So, if I get the Ford performance tune (100hp engine bump with upgraded air intake) and use 93 octane gas will I get 148mph, I should...correct?

Terry

Terry I have to ask why this need to get to 148 MPH? I hope your going to “Mexico” to do 126. Also, you have been on the forum for over 3 years. The HP loss on 87 is well known on the EB. You sound like someone who wants maximum performance. Why haven’t you been using 93 all along?

 

[ChiTownStang26]

@bigyzf

Never said I have proof besides what I've viewed with my own car. You can put 87 in your just going to knock alot more frequently especially under load. You can do what you want with your car but to me it seems silly to pay this much for a car only to drive around with engine knock which may or may not cause premature engine wear. Again no proof but makes sense to me at least. I'm dont care about hp gains I care about having repetitive consistent engine knock day in and day out, especially when ringing my car out to 7k.

That's just me and if anyone has a way to datalog the knock sensor and can run 87, take it on the highway, you'll be as surprised as much as I was how much it knocks. It "feels" low on power to some people because its removing timing because your knocking.

My engine is fine and sees -5 on the knock at WOT with e85, as someone else stated your more prone to knock with a lower octane rating and you will.

Guess it comes down to if you care or not.

 

[TexasRebel]

So it appears that the only way to get above 126mph is to get a tune that will take the limiter off of the engine program.

It seems silly to me that Ford markets a sporty car, lists the top end at 148mph and then limits the car to about 125mph....because they don't want people to out drive the crappy stock tires.

Terry

Yep... that's how an electronic speed limiter works. Doesn't matter what gear you are in, what pitch you're at, how hard you mash the pedal, when that needle matches the governor setting you're not going any faster (save maybe a freefall).

Ford markets the 148mph top end (your claim, I'm not here to verify that) based on specific options. One of those options is tires rated to handle that speed. They also have to shoulder the liability of doing something unethical like telling somebody their car will go 148mph and providing tires that disintegrate at 130mph. There are many people in the market for a mustang only for the look (think 16 year old girls) who likely have a strict budget and will skimp on things they don't understand like... paying extra for tires that have a higher speed rating when all roads are under 85mph.

 

[1mic]

The drive shaft balancing is also a reason Ford limits speed. There were some problems a few years back with drive shafts exploding at high speeds.

There was a thread here where people were defending getting cheap gas for their mustang GT. I always laughed when I read the comments. I want the most HP i can get, so I get premium. For all my vehicles.
If you're on a budget, why not get a cheap daily driver? My daily driver was $3k. Even that gets premium gas.

 

[Deleted member 35786]

@bigyzf

Never said I have proof besides what I've viewed with my own car. You can put 87 in your just going to knock alot more frequently especially under load. You can do what you want with your car but to me it seems silly to pay this much for a car only to drive around with engine knock which may or may not cause premature engine wear. Again no proof but makes sense to me at least. I'm dont care about hp gains I care about having repetitive consistent engine knock day in and day out, especially when ringing my car out to 7k.

That's just me and if anyone has a way to datalog the knock sensor and can run 87, take it on the highway, you'll be as surprised as much as I was how much it knocks. It "feels" low on power to some people because its removing timing because your knocking.

My engine is fine and sees -5 on the knock at WOT with e85, as someone else stated your more prone to knock with a lower octane rating and you will.

Guess it comes down to if you care or not.

If you car is knocking then you have an issue.. albeit most likely because of your tune. A factory stock GT does not knock nor should it running 87 octane.
Your statement should say "you would be surprised how much my tuned coyote engine knocks without premium gas".. Not a factory one. Just saying..
Not trying to bust your balls, but alot of folks will have the impression that all factory coyote engines knock by that unproven statement. You be surprised how gulible folks are.

Sponsored