91 octane or 94 octane: petro ca vs shell

[jw01]

So asking if any of you are expert in this field. ...I typically find the shell 91 price to be the same as petro 94. Is she'll better than petro for your car or vice versa?

I have one German and one English made car and I typically opt for petro ca ....I like their point system and 94 gas options seems more cleaner or refined than the 91.

Is there method to my madness or is it all thr same?

 

[Blake_xo]

I race cars in my non sp life. There's really no need for 94 unless your car is highly modified to be Honost. Vpower is always a safe bet for German cars especially if they are turbo'd from factory. So I'd go with the vpower 91. The 94 I wouldn't recommend because your car most likely isn't tuned for 94 octane and it won't give you any benefit and will
Probably work against your car because it's not tuned for higher octane.

 

[GameBoy27]

Before you waste money on something you don't need, read this and then check if premium is recommended or required for your vehicle.

http://www.edmunds.com/fuel-economy/to-save-money-on-gas-stop-buying-premium.html

Premium Recommended

http://static.ed.edmunds-media.com/unversioned/img/pdf/premium.gasoline/premium.recommended.032714.pdf

Premium Required

http://static.ed.edmunds-media.com/unversioned/img/pdf/premium.gasoline/premium.required.032714.pdf

 

[greyhaired]

I've been told that Shell v power is the only gas which doesn't have ethenol in it which means that it won't collect water like most gasolines and which makes it the fuel of choice for storing stuff like lawn mowers or snowmobiles or motorcycles cause it won't screw up carbs and gas tanks etc

 

[Blake_xo]

Yes all shell vpower is ethenol free. Ethenol can leave residue on valves and make performance lag. You also get better gas mileage with vpower

 

[onthebottom]

I thought I read somewhere that Ferrari required Shell gas - it's what I put in my new Corvette.

 

[GameBoy27]

I've been told that Shell v power is the only gas which doesn't have ethenol in it which means that it won't collect water like most gasolines and which makes it the fuel of choice for storing stuff like lawn mowers or snowmobiles or motorcycles cause it won't screw up carbs and gas tanks etc

You should use this in anything which sits for an extended period of time. Fuel goes bad after 4 months. If you do use a fuel containing ethanol it's not a bad idea to use a gas-line antifreeze from time to time.

 

[Why Not?]

Both are good fuels and part of the "Top Tier Gas" alliance. http://www.toptiergas.com/retailers.htm

Top Tier gas retailers are recommended by BMW, General Motors, Honda, Toyota, Volkswagen, Mercedes-Benz and Audi. http://www.toptiergas.com/

Octane rating is simply a measure of the fuel's resistance to knock. It doesn't imply that it is more refined. Just that the mix of chemicals in the fuel has more knock resistance. If you car's motor is turbocharged or high compression it probably recommends higher octane due to the high compression seen in those engines. It may even recommend a specific octane number. Mine recommends 94 with a minimum of 91. I use Vpower though because it is ethanol-free. I understand that Petro-Can's Ultra 94 has some ethanol. Read your owner's manual and don't waste your money on anything higher than that recommended. I would use Top Tier gas though as it has more detergents than other brands.

 

[james t kirk]

In my classic car (circa 1969 through 74), I only use 94 from PC. That's because I've shaved the head to achieve a 9.75:1 compression ratio AND, I've advanced the timing in order to improve acceleration.

That said, ethanol in gasoline is a very very very bad thing. It will gum up a car's engine in no time flat. My sister has a newer Audi Q5 with the 3.2 litre motor and the engine was so fucked up by ethanol in the fuel that the vehicle had to have the engine pulled and torn apart in order to clean out the gum from ethanol. Audi is well aware of the problem. Fortunately for her, the car was still under warrantee and she was told that Audi is extending the warrantee on this issue.

In my case, I've seen the damage ethanol can cause to the old carbeurator engines. Fuel bowls look like they have been running on swamp water, valves gummed up, fuel pumps fucked up.

This stuff is a disaster and should be avoided at all costs.

I emailed PC, Esso, and Husky asking them all specific questions about ethanol. Only Husky would say that their 91 Octane fuels do not contain ethanol EVER. PC and Esso both avoided the question and gave some BS nonanswer response.

I had been told that Shell fuels don't contain ethanol by a friend and now I'm reading it here too.

I think a switch to Shell is in order.

 

[GameBoy27]

Octane rating is simply a measure of the fuel's resistance to knock. It doesn't imply that it is more refined. Just that the mix of chemicals in the fuel has more knock resistance.

High octane fuel has a higher flash-point for a more controllable combustion. It actually burns a little bit slower and it is harder to ignite which is good for high compression, turbo and supercharged engines and reduces the chance of pre-ignition (detonation). It should be noted that if you use regular fuel in car that requires high octane, anti-knock sensors will simply retard the timing to prevent pre-ignition to prevent damaging the engine. In this case you may notice a slight decrease in power but unless you're driving at full throttle everywhere or turning laps at a race track, you likely won't notice any difference.

If you car's motor is turbocharged or high compression it probably recommends higher octane due to the high compression seen in those engines. It may even recommend a specific octane number. Mine recommends 94 with a minimum of 91. I use Vpower though because it is ethanol-free. I understand that Petro-Can's Ultra 94 has some ethanol. Read your owner's manual and don't waste your money on anything higher than that recommended. I would use Top Tier gas though as it has more detergents than other brands.

Then you shouldn't waste your money on 94.

 

[Why Not?]

Then you shouldn't waste your money on 94.

You really need to learn how to read before you post. My post clearly says that I use Shell Vpower which is 91 octane as clearly stated earlier in the thread.

 

[GameBoy27]

You really need to learn how to read before you post. My post clearly says that I use Shell Vpower which is 91 octane as clearly stated earlier in the thread.

Easy there cowboy... I did read your post. I didn't say you use 94 only that you shouldn't waste your money on it. Simply a message to all who don't actually need the higher octane but use it anyway thinking higher is better. Hopefully this helps clear things up so your blood pressure can return to normal.

 

[whitewaterguy]

I use the shell or alternately the top grade petro-can for my Harley. Was told that neither have the ethanol in them. When Neither are available to me on a road trip, it becomes clearly evident quickly by way of pinging and tapping under load and acceleration

 

[surferboy]

Just read the owners manual,if it calls for 91 use 91.Putting in 94 won't give you anymore performance,at least in a computer controlled engine.If it calls for 94(which rarely they do)go to the busiest gas station that sells 94.Since it has ethanol it absorbs moisture & dies faster the longer it sits in the underground tank & condensates.If it sits there longer than a month, your basically getting 91 octane! Sunoco 94 was the best,until they started to add ethanol & take out mtbe.Damn tree huggers!

 

[surferboy]

I race cars in my non sp life. There's really no need for 94 unless your car is highly modified to be Honost. Vpower is always a safe bet for German cars especially if they are turbo'd from factory. So I'd go with the vpower 91. The 94 I wouldn't recommend because your car most likely isn't tuned for 94 octane and it won't give you any benefit and will
Probably work against your car because it's not tuned for higher octane.

A higher octane will never work against you!

 

[hi up in the sky]

The debate of ethanol or not has been going on for a long time. Ethanol burns at a cooler temperature and raises the octane when added to gas. Some high performance cars are designed with higher compression, specifically many MB, BMW, Porsche and Audi products. Ethanol can produce more power in a high compression engine than gasoline, but it requires a larger volume (more gas) before it will produce said extra power. Nowadays many cars with the sophisticated engine management sytems will adjust the air fuel mixture and timing to optimize the engine for whatever the manufacturer prioritizes, usually fuel economy and/or performance. most will adjust timing to reduce detonation. this means that even if your car is optimized for 98 octane (MB E63 for example), the car will adjust itself. i dont rememebrr the exact math but I think on a 500 horsepower V8 a five point octane reduction would need a timing adjustment that would cause a loss of about 8 horsepower. it would also reduce fuel economy. Petrocanada has a published "up to 10%" ethanol content. Shell has no ethanol.

 

[icespot]

You guys do realice that they use the same truck to deliver 87 to 94 oc. I know frlm a good source that if the truck still has 87oc when it returns to pick up 94 or 91 they dont empty the truck of 87oc. Why they do this? Because they make shit loads mord money and they can get awah with it.

 

[DanJ]

One of our mechanics from work has an old Dodge Dart that he has done all sorts of work to over the years and he races it from time to time. He goes over to the airport for fuel for it. Not sure whether he uses Avgas or Jet Fuel, or why, as I'm not a mechanic lol.

 

[GameBoy27]

You guys do realice that they use the same truck to deliver 87 to 94 oc. I know frlm a good source that if the truck still has 87oc when it returns to pick up 94 or 91 they dont empty the truck of 87oc. Why they do this? Because they make shit loads mord money and they can get awah with it.

I have a hard time believing that it's as simple as not emptying the tanker of 87 then filling it up with 94 to "make more money". A little proof to back up your story would be nice.

One of our mechanics from work has an old Dodge Dart that he has done all sorts of work to over the years and he races it from time to time. He goes over to the airport for fuel for it. Not sure whether he uses Avgas or Jet Fuel, or why, as I'm not a mechanic lol.

If he's going to the airport for fuel then he's buying Avgas and not Jet Fuel, that's Kerosene which won't work in a car. I used to run 100/130 Avgas in my racecar which has been replaced by 100LL which stands for Low Lead.

A higher octane will never work against you!

Actually, that' not true. One day I decided to fill my motorcycle tank with 100/130 Avgas thinking it would run better. Well, it wouldn't even start. l had to drain the tank and fill it with regular. lol

 

[abv]

One of our mechanics from work has an old Dodge Dart that he has done all sorts of work to over the years and he races it from time to time. He goes over to the airport for fuel for it. Not sure whether he uses Avgas or Jet Fuel, or why, as I'm not a mechanic lol.

It would be Avgas. Jet A can replace diesel not gas.
Avgas is 110-112 octane leaded.