Premium Fuel Required?

I just got a new car and it mentions in the owners manual that premium fuel was 'recommended'. Any of you car types out there know if I could damage the engine by using el cheapo fuel. Is the premium only recommended for optimum preformance? If so, what exactly is 'optimum performance'?

Thanks

[@theCBE]

From my understanding it depends on the Car and Engine type .. for example if your engine has a Turbo then yes you should be using Premium gas. My Dad actually started getting much better gas mileage once he started using premium gas as the owners manual suggested.

[Ironhorse]

Premium fuel, in addition to the higher octane rating, will sometimes also contain additional detergents.

Octane rating is the most important. The higher the rating, the more compression it can withstand before detonating. This is very important in vehicles with higher compression ratios, typically turbo / supercharged & performance engines. These days, a lot of engines' ECU can compensate for inferior octane / fuel, but it is still not good for the engine, and your mileage will also suffer.

Short story, put in what the manual recommends.

[photon]

I know if I put in the middle octane stuff in my car it will "knock" (the gas detonates before it's supposed to) and of course my milage goes down too.

There is a station called Centex around Calgary that charges only 6 cents above regular for premium, and has 2 cents off on Wednesday, Saturday, and Sunday. And their prices are also lower, so I usually pay for premium what most other stations have for regular.

It's not a turbo and supercharged emgine... its a VW V6 engine in an '07 Touareg.

[photon]

Yeah I've got a V6 VW Passat.. different engine I believe (mine is 2.8L), but same idea; if you have lower octane then the fuel can detonate early (before the spark).

[Eddie Bronze]

Originally Posted by photon

There is a station called Centex around Calgary

I could be wrong but I think there's only five of those in the entire city. Good deal if you don't have to drive to find one of them, though.

[photon]

Only 5? Man that sucks.. There was one within a few blocks where I used to live, and now there's one directly between my work and my home, so I guess I'm lucky

[Bingo]

I have a Ram with the 5.7 Hemi in it ... any thoughts on that for premium?

[ken0042]

I've always used premium or mid-grade in my vehicles. I found that the increase in fuel economy offsets about 1/2 of the price increase.

[photon]

Originally Posted by Bingo

I have a Ram with the 5.7 Hemi in it ... any thoughts on that for premium?

Usually says in the manual or right inside the gas cap.

[Shazam]

Originally Posted by photon

Only 5? Man that sucks.. There was one within a few blocks where I used to live, and now there's one directly between my work and my home, so I guess I'm lucky

Yeah, I used to work by the one in Inglewood. It was great.

[Looger]

knock sensors will ###### timing a few degrees on most modern engines so if you like smooth performance then that's the major reason most people put high-test in.

not totally required but if you drive with a heavy foot i'd recommend it.

much better for forced induction, as mentioned above.

[Bill Bumface]

Originally Posted by ken0042

I've always used premium or mid-grade in my vehicles. I found that the increase in fuel economy offsets about 1/2 of the price increase.

If I recall you drive a Grand Am, which only requires 87 octane. Putting anything above 87 actually slows your car down and decreases fuel economy.

At our altitude lots of naturally aspirated cars can actually get away with going below their octane recomendation because of our thin air.

[REDVAN]

Originally Posted by hulkrogan

If I recall you drive a Grand Am, which only requires 87 octane. Putting anything above 87 actually slows your car down and decreases fuel economy.

At our altitude lots of naturally aspirated cars can actually get away with going below their octane recomendation because of our thin air.

I also drive a Grand Am and I know for a FACT that it says in the manual that thie engine requires 87 octane. I mean, it's designed for "regular" gas, so why put in expensive gas? It's not a performance engine that requires it anyway.

[Dion]

Put simply, vehicle manufactures specify a fuel octane rating for each car produced to ensure maximum performance and reduce knocking / pinging under normal conditions.

It is recommended that motorists use fuel with at least the octane rating suggested by the vehicle manufacturers. When discussing this matter with oil company representatives, they said that there is no harm in using a fuel with a higher than recommended octane rating. Conversely, there is no guaranteed benefit either. There may however be a loss of vehicle performance if a lower than recommended octane fuel is used. Many imported and performance cars are designed to use higher octane fuels. Some of these cars can use lower octane fuel, but may suffer consequent loss in performance. Others have engine management systems that can detect the octane of fuel and adjust the engine timing to suit that octane.

http://motormouth.com.au/newsletters/1103.htm

[Dion]

Originally Posted by hulkrogan

If I recall you drive a Grand Am, which only requires 87 octane. Putting anything above 87 actually slows your car down and decreases fuel economy.

At our altitude lots of naturally aspirated cars can actually get away with going below their octane recomendation because of our thin air.

No. It does not hamper your performance in any way

[Sylvanfan]

Well from what I understand the higher the octane level the cooler the engines burning temperature. So if your vehichle is reccomended to use regular, than use regular fuel becuase your engine will operate at the temperature that it's designed to get optimal perfomance.

Conversely if you put the regular in a vehichle that requires 91 octane fuel, you're engine isn't going to get peak perfomance and operate at it's maximum efficiency.

Didn't they tweak the V6 in the Toureg to get it up to like 245 horse for 07. I was looking at Toureg's earlier, but could only afford a used one. I didn't like the power of the old V6 and the V8 was just going to be too expensive to run.

[Sylvanfan]

Originally Posted by Dion

No. It does not hamper your performance in any way

Clarification?

With the higher altitude going below your reccomending octane won't hinder your vehichles performance.

From what I understand that would be the correct statement as most engines are tested and calibrated for lower altitude operating conditions. My brother is a big time car guy and had his engine tuned out to run with 94 octane gas when he was living in BC's lower mainland, and said he had to use regular fuel on a trip to Yellowstone park due to the alititude to get his car to have any type of performance there.

[browna]

Just got a new (used) vehicle (two weeks ago after turning in my lease, sadly, somewhat), that requires premium (Acura MDX).

Thanks for the headsup on Centrex...one not that far out of the way, on Elbow.