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What octane gas in my GTH ?


cobraguy69
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Just got mine ! A gorgeous 2016 Mustang Shelby Hertz. . The first thing I had to do was put some gas in it, so I looked in the owners manual and it said for the 5.0 engine to use 87. I called the previous owner ( it was a licensee car - never rented ) and he said he always used 93 " to avoid the ethanol ". Where I live all grades of gas have ethanol , and in fact, to my knowledge ethanol is added as an inexpensive way to boost octane rating, so I am asking you owners of this car, or any Mustang GT- What do you use, and have you found it makes a difference either way. I am thinking I should do what Ford says - 87.

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Thanks Guys - Lovin' this beauty ! Most guys I talked to use the higher grades - but, as a new owner reading the manual " Use of any fuel other than the recommended fuel can cause powertrain damage, impair the emission control system or cause loss of vehicle performance. Any damage to vehicle that is caused by use of fuel not recommended will not be covered under warranty ". And recommended fuel is 87, but no less. Does say " To provide improved performance, we recommend premium fuel for severe duty usage, such as trailer tow. Not going to be doing that.This car is 1&1/2 yrs. old with 5K miles and might be still covered under warranty, that is another question I need to look into.

I know, nervous new owner, but that's why I'm here asking. Thanks again for any help, John.

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Just got mine ! A gorgeous 2016 Mustang Shelby Hertz. . The first thing I had to do was put some gas in it, so I looked in the owners manual and it said for the 5.0 engine to use 87. I called the previous owner ( it was a licensee car - never rented ) and he said he always used 93 " to avoid the ethanol ". Where I live all grades of gas have ethanol , and in fact, to my knowledge ethanol is added as an inexpensive way to boost octane rating, so I am asking you owners of this car, or any Mustang GT- What do you use, and have you found it makes a difference either way. I am thinking I should do what Ford says - 87.

 

Unless you have specific engine upgrades like a supercharger with higher capacity injectors and tune there is nothing to be gained by using an octane rating other than what is in the owners documentation. Octane does not improve gas mileage or anything other magical than retarding knock. Except that it costs more.

 

All modern engines will operate just fine with the 10% ethanol. Older vehicles rubber components could fail but not new stuff.

 

One more hint that it is all you need: Hertz is not going to place into service a vehicle that needs anything other than the cheapest grade of gas you can buy since that is precisely what everyone that returns a car will use.

Edited by twobjshelbys
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Thanks Guys - Lovin' this beauty ! Most guys I talked to use the higher grades - but, as a new owner reading the manual " Use of any fuel other than the recommended fuel can cause powertrain damage, impair the emission control system or cause loss of vehicle performance. Any damage to vehicle that is caused by use of fuel not recommended will not be covered under warranty ". And recommended fuel is 87, but no less. Does say " To provide improved performance, we recommend premium fuel for severe duty usage, such as trailer tow. Not going to be doing that.This car is 1&1/2 yrs. old with 5K miles and might be still covered under warranty, that is another question I need to look into.

I know, nervous new owner, but that's why I'm here asking. Thanks again for any help, John.

 

There is an exception. High altitude areas almost always have gas with octane two points down. Ie, 83 vs 85, 85 vs 87 and 89 vs 91. That is to compensate for the lower oxygen content in the air.

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I would verify this with Steve here first but researching the subject, according to the press release, doesn't mention any engine mods. Not even a tune, only a Ford Performance cat-back exhaust. So yes, in that case, it is able to run on the 87 octane gasoline if it has not had a performance tune installed.

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Mine is an un-modified GT-H, which is a 5.0 GT engine and running fine on 87, I will not be racing- At most may find a stretch of road to put it in Sport Mode. It seems to be very happy with 87 so far.

Like the previous posters said if there has been no performance items added 87 octane is fine, to go to 93 is just wasting your money.

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I would verify this with Steve here first but researching the subject, according to the press release, doesn't mention any engine mods. Not even a tune, only a Ford Performance cat-back exhaust. So yes, in that case, it is able to run on the 87 octane gasoline if it has not had a performance tune installed.

Correct, the computer tune was NOT changed by Shelby American so the minimum octane of 87 as recommended by Ford is just fine.

 

Now with that said I suppose if I was travelling up some significant grades at speed during the summer months I would probably step up to 89 octane for that trip but to run say 93 octane all year round, well all you would be doing is increasing the price of oil stock.

 

Steve

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I think perhaps there may need to be more clarification and/or a verification about the octane requirement for the 2016 GTH. It has been stated that 87 is in the 2016 Owners Manual. True, but that manual doesnt take in to account a Ford Performance Calibration. It has also been pontificated that Hertz wouldnt release a car in to the fleet that would require more than 87 octane because customers would just refill it with the cheapest 87 octane they could find. Thats statement is half true, yes it is probably true that customers will probably refill with 87 because it is less expensive, but Hertz has had performance cars in its fleet that require higher than 87 octane for optimal performance and if the 2016 Shelby GTH is advertised correctly it does indeed require 91 octane for optimal performance. Why? Because its states on the Hertz website that the 2016 GTH has the Ford Performance Calibration Kit # M-9603-M8.
On the Ford Performance Website it states that the # M-9603-M8 Kit is a Ford Performance Calibration and a K&N Hi Flow Filter that yields an extra 13 hp and an extra 40 ft lbs of torque and it clearly states that Premium Fuel,91 Octane or higher is required for the Ford Performance Calibration. I think SAI Steven mentioned there were no tunes done at Shelby. However, Hertz appears to currently be advertising that there is a Ford tune?

With the above being stated, it probably doesnt hurt to run a 2016 GTH on 87 but to get optimal performance and to maximize the advantage of the Ford Performance Calibration Kit # M-9603-M8 (if it is included as currently advertised by Hertz) then Ford does require 91 or higher.

Edited by mhr1961
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Because its states on the Hertz website that the 2016 GTH has the Ford Performance Calibration Kit # M-9603-M8.
On the Ford Performance Website it states that the # M-9603-M8 Kit is a Ford Performance Calibration and a K&N Hi Flow Filter that yields an extra 13 hp and an extra 40 ft lbs of torque and it clearly states that Premium Fuel,91 Octane or higher is required for the Ford Performance Calibration.

 

Well we need to dig deeper then as that contradicts the press release and marketing material when the GTH was released.

 

Attached is a screen capture of the 2016 GTH hero card with no mention of a calibration kit.

2016 GTH Specs.jpg

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Also if SAI was to install a "FRPP calibration kit" I'm pretty sure we would be required to affix a Executive Order emission decal under the hood letting service technicians know that the cars computer has been modified. I also don't recall a octane sticker being placed on fuel door.

 

mhr1961, do you have a link to the Hertz website where they are stating that the 2016 GTH cars were equipped with a FRPP calibration?

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Hi Steve, here is the link to the Hertz page where they are advertising the 2016 GTH for sale. Please note: In my post #14 above I stated " if the 2016 Shelby GTH is advertised correctly it requires 91 octane".

 

https://www.hertzcarsales.com/2016-shelby-mustang

 

And below is the cut and paste from the Hertz website and it does state under "Ford Options" that it has the Ford #M9603-M8 calibration.

 

Buy one of the 2016 Shelby Mustang GT-H today!

Hertz originally partnered with Ford and Shelby creating the 1966 Shelby GT350-H, for the new “Rent-A- Racer” program with 1,000 produced. Then in 2006 Ford and Shelby connected again producing just 500 Ford Mustang Shelby GT-H’s coupes and 500 convertibles. Hertz is joining Ford and Shelby once again for a limited production run of 2016 Ford Shelby Mustang GT-H Premium 50th Anniversary Editions.

 

View Shelby Inventory

 

 

Exterior: Shadow Black with Gold Striping

 

Interior: Ebony Leather

Engine & Transmission:

· 5.0 Liter Coyote V-8

· 6-Speed SelectShift® Automatic transmission with paddle shifters

· 3.55 Limited Slip Rear Axle

 

Ford options include:

· Navigation system

· Ford Performance Handling Package (M-FR3A-M8)

· Ford Performance Cat/Back exhaust - touring/chrome tip (M-5200-M8TC)

· Ford Performance Calibration (M-9603-M8)

· Staggered wheel kit (M-1007K-M19XB)

· Hertz/Shelby center wheel cap (M-1096-HS)

· Hertz/Shelby mirror puddle lamp (M-13374-HS)

 

 

Shelby Installed Options Included:

Exterior:

· Carbon Fiber Front Splitter

· Polycarbonate Hood

· Hood Paint

· Washer nozzle relocation kit

· Carbon Fiber Shelby GT Rear Spoiler

· Unique Shelby GT-H Grilles

· GT-H Stripping Installed

· Hertz Fender Emblem

· Front Grille Emblem

· C-Pillar Shelby Emblem

· Rear SHELBY Letters

· Faux Shelby GT-H Gas Cap

 

Interior:

· Dash Plaque

· Headrest Cover set w/Hertz logo

· Hertz Floor Mats

· Hertz Backlit Sill Plates LH/RH

 

Engine Dress-Up

· Engine Plaque

· Shelby GT-H Engine Cap kit


 

Click to View Available Inventory

Edited by mhr1961
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I filled up #130 (vin 299390) today for the first time...after figuring out how to open the fuel door...and there was a 91 octane label in the fuel opening. Brent

post-14234-0-87901700-1510463095_thumb.jpg

Edited by blz57
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I filled up #130 (vin 299390) today for the first time...after figuring out how to open the fuel door...and there was a 91 octane label in the fuel opening. Brent

Thanks for posting the picture. Just confirming,your GTH a 2016 model? Edited by mhr1961
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Perhaps we do know now, but after I pointed out that the 2016 GTH may have the Ford M9603-M8 per Hertz current advertisement, it will still for posterity sake and for the good of the Hertz Nuttz crowd to have an updated/corrected official statement from SAI(and/or Hertz) because it is odd that they did not have this option mentioned in the original marketing of the vehicle and it would have helped in differentiating the car and perhaps making it more popular in that if it does have the Ford tune it had 13 more hp and 40 ft lbs more torque and tighter shifting than a regular ol mustang GT.

Edited by mhr1961
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I have looked at pics of cars for sale from Hertz (not all of them) and EBAY - for pictures of the engine compartment. Many don't show the engine. Many that do have a pic do not have the K&N sticker visable, but some do: # 121, 132, 141, 116 on EBAY and 159 on EBAY (got 159 off the CSM picture).

 

So a bit of a mystery, my #130 has the 91 Octane and K&N sticker.

 

I know # 49 is owed by Frontier Ford and # 131 (sequential in CSM & VIN to mine) is on its way to Frontier Ford. I am stopping by there in the morning, will check on these two 2016 GT-H's. Brent

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The K&N sticker is so that oil change shops don't throw the filter out and replace it with a paper filter.

 

The 91 octane sticker is an important clue but more importantly if these cars have the FRPP calibration kit where is the EO decal? EO stands for executive order and is a number assigned to a performance part stating that the part does not violate emission requirements.

 

I've checked the SAI invoice and this FRPP calibration is not listed on the invoice BUT that is not a smoking gun item as Hertz purchased the FRPP parts from Ford and supplied these parts to SAI.

 

This needs more research.

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I filled up #130 (vin 299390) today for the first time...after figuring out how to open the fuel door...and there was a 91 octane label in the fuel opening. Brent

This is getting interesting. I just looked up the invoice for #130 and that invoice shows :

 

HM-9603-M8 FORD HERTZ CALIBRATION

 

so when I looked up another GTH the other day why was there was no calibration listed for that GTH?

 

blz57, is your GTH an actual ex-rental car or was it one of the executive / licensee cars?

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