[VF-22]

Originally Posted by laborsmith

I am going to disagree with this conclusion because the ecu needs to perceive knock to change table that means every time one desires to start the engine and drive away there will be a series of the knock sensor changing fuel maps one step at a time until no knock is picked up.

At least that is my perception of how it works but if I am wrong I am certain one of our member engineers will set me straight.

Laborsmith

Look at this PDF for the Mustang. The recommended is 87 across the board. Anything else being used is a waste of $$$ unless you are tracking/racing it.

https://media.ford.com/content/dam/f...tang_Specs.pdf

If the recommended fuel is 87, then that is all you need.

If the LT1 says recommended premium (91/93), then that is what you need to run because that is what they have set up everything for. I don't have the LT1 or engine specs on them. Obviously you shouldn't run 87 in a engine that has a recommended of 91.

Im going to assume that the SS is going to recommend/require premium because the Fuel.gov tests are running it for the Corvette. They only run the required fuel for these tests.

http://www.fueleconomy.gov/feg/Power...te&srchtyp=ymm

[Geno]

Is there any advantage or power boost to running premium in the V6? My Genesis Coupe is only a 4HP difference.

[SSport16]

Originally Posted by VF-22

Look at this PDF for the Mustang. The recommended is 87 across the board. Anything else being used is a waste of $$$ unless you are tracking/racing it.

https://media.ford.com/content/dam/f...tang_Specs.pdf

If the recommended fuel is 87, then that is all you need.

If the LT1 says recommended premium (91/93), then that is what you need to run because that is what they have set up everything for. I don't have the LT1 or engine specs on them. Obviously you shouldn't run 87 in a engine that has a recommended of 91.

Im going to assume that the SS is going to recommend/require premium because the Fuel.gov tests are running it for the Corvette. They only run the required fuel for these tests.

http://www.fueleconomy.gov/feg/Power...te&srchtyp=ymm

I almost certain it is going to say recommended 91 or higher. I believe all of GM's late model engines in the Camaro and Vette were all listed as such. I know my old LS1 in my '98 SS listed it that way and I believe still continues even into the current LT1/LT4 in the Vettes.

[GretchenGotGrowl]

Originally Posted by Geno

Is there any advantage or power boost to running premium in the V6? My Genesis Coupe is only a 4HP difference.

We saw about 5 RWHP on the old LLT. Tune it and you will see more than that though.

[VF-22]

Originally Posted by SSport16

I almost certain it is going to say recommended 91 or higher. I believe all of GM's late model engines in the Camaro and Vette were all listed as such. I know my old LS1 in my '98 SS listed it that way and I believe still continues even into the current LT1/LT4 in the Vettes.

Yah if that's the case then for certain the SS will need that in it.

Curious to know what the V6 is going to recommend. I hope 87.

Originally Posted by Rocco70

Another dumb question to add to the list of dumb question on here

It's actually not a dumb question. Lots of idiots are parted with their $$$ by running premium fuels when they don't need to.

[drivingagain]

Not a stupid question but not sure why no one talked about compression ratio. This is the main determining factor for fuel octane. Timing and efficiency of head design etc. obviously plays a huge part as well. If I am not mistaking the camaro is running a 11:5 to 1 compression ratio this is definitely premium gas. If it were not for the knock sensors we would not see this compression in a car engine. This engine is going to like 93 octane the best. Has to be able to run 91 because of California.

On a side note the higher the octane does not produce more power. It just retards the flame when the gas ignites. Technically 87 octane has a higher burning temperature or BTU then 93.

I feel all 3 engines will prefer premium over 87. We are talking about high efficiency high compression engines. Also you can get away with lower octane fuel now a days but your gas mileage will suffer. Why bother running the wrong fuel? Example Nissan in my opinion for years produced the most efficient v6 production car engines in the world for years. Notice a huge difference between 87 and 93 when you do your mpg's.

[SSport16]

Originally Posted by VF-22

Yah if that's the case then for certain the SS will need that in it.

Curious to know what the V6 is going to recommend. I hope 87.



It's actually not a dumb question. Lots of idiots are parted with their $$$ by running premium fuels when they don't need to.

V6 should be 87...I have the current 3.6 in my SRX, and it is 87 only, so I am sure the same for the new V6.

[laborsmith]

I recall the ATS 2.0T recommends using premium and the 3.6 using regular.

But those are Cadillac installs and maybe Chevy is using something different.

Laborsmith

[Ragnar]

Originally Posted by bdavies11

Other than reduced power, are there any other reasons not to use premium fuel? Would long term use of 87 octane be bad for the lt1?

In my owners manual for an L99 or LS3, use 91 or higher octane. Regular 87 octane can be used, but acceleration and fuel economy will be reduced, and an audible knocking noise may be heard. If this occurs, get 91 octane ASAP. Otherwise, engine could be damaged.

[GretchenGotGrowl]

Originally Posted by drivingagain

Not a stupid question but not sure why no one talked about compression ratio. This is the main determining factor for fuel octane. Timing and efficiency of head design etc. obviously plays a huge part as well. If I am not mistaking the camaro is running a 11:5 to 1 compression ratio this is definitely premium gas. If it were not for the knock sensors we would not see this compression in a car engine. This engine is going to like 93 octane the best. Has to be able to run 91 because of California.

On a side note the higher the octane does not produce more power. It just retards the flame when the gas ignites. Technically 87 octane has a higher burning temperature or BTU then 93.

I feel all 3 engines will prefer premium over 87. We are talking about high efficiency high compression engines. Also you can get away with lower octane fuel now a days but your gas mileage will suffer. Why bother running the wrong fuel? Example Nissan in my opinion for years produced the most efficient v6 production car engines in the world for years. Notice a huge difference between 87 and 93 when you do your mpg's.

You have to remember, that DI and more sophisticated programming in these larger ECUs has allowed them to run high compression engines on lower octane. The LFX has a 11.5:1 CR and can run 87.

[SpeedIsLife]

Originally Posted by VF-22

If the engine is designed to run on 87, then that's all you need. With today's engines/sensors there is no point to run a higher fuel unless the engine requires it or you are tracking it. Engines like Audi's require premium because they are designed for it.

The power reduction will not be noticeable to 99% of the drivers in the V8 or V6. The Turbo is the one that WILL notice it.

The Mustang engines are designed to run on 87 (all 3 trims) via their user manuals, but the EB is the one that is affected the most by running 87 due to it's HP going from 310 to about 279 vs Premium. That's why they advertise with the * for the EB.

As for the GT, it also gets an * but it takes a 1% HP hit running 87 so the 435HP is dropped to about 430HP which no one is going to notice unless they are tracking it.

Now if the LT1 is designed baseline to run on 91 or 93, then you NEED to put that in it.

So in reality, if it's not designed to run on 91 or 93, it just doesn't make sense to run 91 or 93 for the majority of buyers. Wasting big time $$$.

Fuels today if they are Top Tier are not going to damage your engine at all if you run 87.

www.toptiergas.com

You speak incorrectly sir.

The LT1 is rated at 91 octane. Just because it can run 87 or 89 doesn't mean you should, it's more so intended to get you home if you can only get 87.

[drivingagain]

Originally Posted by GretchenGotGrowl

You have to remember, that DI and more sophisticated programming in these larger ECUs has allowed them to run high compression engines on lower octane. The LFX has a 11.5:1 CR and can run 87.

Yes you are right DI has changed some of the variables and why we can now see a 12.5 to 1 compression on 93 or pump gas. The V6 is going to be regular fuel just looked it up. Compression ratio: 9.5:1 for 2016 chevrolet camaro v6.

[GretchenGotGrowl]

Originally Posted by drivingagain

Yes you are right DI has changed some of the variables and why we can now see a 12.5 to 1 compression on 93. The V6 is going to be regular fuel just looked it up. Compression ratio: 9.5:1 for 2016 chevrolet camaro v6.

That's the CR for the LTG 4T. The LGX is still 11.5:1.

[VF-22]

Originally Posted by SpeedIsLife

You speak incorrectly sir.

The LT1 is rated at 91 octane. Just because it can run 87 or 89 doesn't mean you should, it's more so intended to get you home if you can only get 87.

I'm not incorrect.

Like I said, if the LT1 is rated/designed to run at 91 and has a recommended fuel of 91, then that is what it should be put in it baseline.

It CAN run on 87 in emergencies according to the Corvette manual. The 87 is only there in case of no available other fuel (like you run out of gas or gas station only has one type). It will get by but you need to get back to the higher octane ASAP or risk damaging the engine. The same applies to Audi engines that are designed to run on 91. You CAN put 87 in there but only in emergencies.

That is a big difference in what I linked about the Mustang engines. All 3 are recommended for 87.

You will not hurt the T4, V6 or V8 engine in a Mustang running 87 EVER. There are lots on the M6G forum telling people they need to run 91 in their V8 or risk engine damage which is entirely a load of crapola.

Originally Posted by SSport16

V6 should be 87...I have the current 3.6 in my SRX, and it is 87 only, so I am sure the same for the new V6.

Is that the same engine going in the V6? If it is the owners manual says this which means it's designed to run on 87. Good to know.

Use regular unleaded gasoline meeting ASTM pecification D4814 with a posted octane rating of 87 or higher. Do not use gasoline with an octane rating below 87, as it may cause engine damage and will lower fuel economy.

Just found this for the LT1/Corvette. So the SS will require 91. Add up the extra fuel costs.

If equipped with the LT1 engine, use premium unleaded gasoline meeting ASTM specification D4814 with a posted octane rating of 91 or higher.

Regular unleaded gasoline rated at 87 octane or higher can be used, but acceleration and fuel economy will be reduced, and an audible knocking noise may be heard. If this occurs, use a gasoline rated at 91 octane or higher as soon as possible. Otherwise, the engine could be damaged. If heavy knocking is heard when using gasoline with a 91 octane rating or higher, the engine needs service.