| Author | Message | ||
| dave handa (Davehanda)
Intermediate Member Username: Davehanda Post Number: 2116 Registered: 5-2001 |
Frank, That may be...but I think the question becomes, "are the different additives statistically significant?" That is, will they help to avoid (or cause) drivability, mileage or maintanence issues? I have been buying the cheapest priced gas (of the appropriate grade the manufacturer recommends) from Arco, Costoc, etc., and have had no ill effects on any of my cars or motorcycle. I know friends who swear they have had problems with these brands, but I wonder if it was not just an instance of "one bad tank" and more the fault of the individual station selling "watered" gas or something...rather than an actual problem with the brand in general. | ||
| Drew Altemara (Drewa)
Junior Member Username: Drewa Post Number: 198 Registered: 2-2002 |
Though the additive packages are a little different they are much closer than they use to be. The Clean Air Act of 1990 mandated that beginning in 1993 (I think, maybe 1992) all gasolines contain port fuel injection (PFI) and intake valve detergent (IVD) additives that have beeen verified in the field. I don't think there is a big difference out there since then. The premium grades get a little heavier additive dose. However if you add too much you run into combustion chamber problems. The brands/companies mentioned are among the better ones with regards to transportation fuels quality. Not only in additive package but in getting it from the refinery, through the pipeline, into the terminal, from the truck, to the station, and into your 4RE. | ||
| Frank Parker (Parkerfe)
Advanced Member Username: Parkerfe Post Number: 3118 Registered: 9-2001 |
I use 93 from either Amoco/BP or Chevron in all my cars. While all brands of the gas itself may be the same, the additive packages are quite different. | ||
| Bob Zambelli (Zam330)
New member Username: Zam330 Post Number: 26 Registered: 8-2001 |
I've been using plain old regular (87 octane?)for just about as long as I can remember. I've tried the different brands and I could not find ANY difference in performance or economy. Hate to admit it but I shop for price! I drive the car quite agressively and no problem so far. Comments? | ||
| dave handa (Davehanda)
Intermediate Member Username: Davehanda Post Number: 2094 Registered: 5-2001 |
Pretty much all you can find in Washington State is 91 octane. I buy where ever I can find it cheapest. This usually means Arco or Costco. I hear people complain about Arco quality all the time, yet I have used it for 15 years in every car I own with no problems. I would agree that the vendor (gas station) selling the fuel has a great influence on the quality. Low volume dealers can have "old gas", may not change their pump filters regularly (every notice how slow it pumps?...dirty filter). We have had a few dealers caught attaching an extension to their "regular" (87 octane) pump and dispensing it back into the "premium" (91 octane) tank, diluting it down to who knows what. That can be a common reason for "bad gas"..... | ||
| Mitch Alsup (Mitch_alsup)
Intermediate Member Username: Mitch_alsup Post Number: 1228 Registered: 4-2002 |
"Contrary to popular belief, higher octane fuel does not mean more power," Agreed, unless the engine is tuned or modified for that fuel. "it actually has less potential energy than lower octane gas." Most of the time this is true, however Tolulene and Xylene have more energy density than regular gasoline because they are more dense (wrt carbon molecules/gallon) "The fuel with the highest "energy content" available to a consumer is diesel fuel." Only when you are restricted to pump fuels.... "The reason to use higher octane gas is so that you can run higher compression" Higher compression or/and more spark advance. "and higher rpm without piston-splitting detonations." Above 3000 RPMs or so, the turbulence in the cylinder makes the gasoline burn faster so more advance is not needed. One must avoid detonation at any RPMs whether high or low. "Octane actually REDUCES gasolines ability to ignite." A side effect of the definition of octane. "Higher compression ratios allow more air per stroke without the compression igniting the fuel before top dead center." Not quite: Higher compression is more efficient at extracting the heat energy from each ignition, AND higher compression is more efficient at eliminating the residual gasses from the previous ignition (than lower compression--assuming the rest of the engine is left unchanged). The volume of the cylinder is not changed. "Treating" your car to higher than required octane is a waste of money. " This depends on how you value the "sound" the engine makes. In my Vette, the engine noise is closer to a sewing machine on high octane, in the F355, it simply sound less strained. I chock both of these up to the slower flame front in the cylinder. The slower flame front does not bang on the top of the cylinder as hard as gasoline that is just barely under the detonation limit, nor odes the slower flame front insert pressure harmonics into the heads. Notice: never have I said that the engine produces more power, but it does SOUND better. TO me this is worth $20 at the track (where the day is already costing my $500). On the road, I just put in the best gas I can find at reasonable prices. I can hear the difference, even when I can't feel the difference. | ||
| Amir (Amir)
Member Username: Amir Post Number: 295 Registered: 2-2003 |
I have always wondered about this too. So I went to a buddy of mine, Andy, who is getting a Master's degree in Petroleum Engineering here at Texas A&M. He also has a Bachelor's in Mechanical Engineering. Andy's answer: Yes and no. Higher octane rated fuel is supposed to burn slower and therefore you can be more precise in timing the movement of the engine's mechanical components and the propagation of the flame/explosive charge/explosion. So you are better able to extract power and avoid detonation, which can detroy engines. Detergents and additives can help to rid your combustion chamber of coke deposits, keeping it all unclogged and working the way it was designed to. But they can create problems of their own. Take advertising claims with a huge grain of salt. You shouldn't need ANY additives. All stations' fuels come from the same filling tanks, and the same refining companies put the fuel there in the first place, from the same holes in the same ground. It's not silk versus cotton. It's all cotton. Labels like Ultra and Optimax are just marketing tricks. It's really unbelievable what companies get away with. But then, people pay more or less for the exact same car from different dealers, or the exact same pair of shoes, so I guess it's no different with the marketing of fuel. Think of the octane level as a finish to the product, rather than different products altogether. Each motor in each car is different. Find the fuel that makes yours run smoothly. That's it. To gain more performance, you need a lot more research. Blueprinting an engine is a good start. Only then should you worry about the fuel you put in...anything better and more consistent would require your own refinery and your own refining or distiallation methods. | ||
| Jay P. Ross (Eilig)
Member Username: Eilig Post Number: 297 Registered: 8-2001 |
In Germany, Shell just introduced a new "V Power" Super Plus (premium) fuel with 100 octane. The Ferrari runs just great on this. The downside, however, is it costs approximately $4 per gallon (all fuel in Germany is expensive). What a joy, spending $100 to fill up your tank! But hey, at least you feel like you're getting something at 100 octane. | ||
| Russ Birch (Pyro)
New member Username: Pyro Post Number: 18 Registered: 10-2003 |
There seems to be quite a bit of confusion among the general public as to when and why higher octane ratings will provide benefit. Contrary to popular belief, higher octane fuel does not mean more power, it actually has less potential energy than lower octane gas. The fuel with the highest "energy content" available to a consumer is diesel fuel. The reason to use higher octane gas is so that you can run higher compression and higher rpm without piston-splitting detonations. Octane actually REDUCES gasolines ability to ignite. Higher compression ratios allow more air per stroke without the compression igniting the fuel before top dead center. "Treating" your car to higher than required octane is a waste of money. Also, regular pump gas contains detergents which help keep your fuel system and heads/valves clean. A blend of race gas and pump gas which yields 95 octane is all that is required to extract maximum potential from a stock engine. My two cents. Russ Birch | ||
| Mitch Alsup (Mitch_alsup)
Intermediate Member Username: Mitch_alsup Post Number: 1227 Registered: 4-2002 |
"but running at a high octane will be better for the engine... will it not?" The engine sounds better, more free or less strained, a tad quieter. I chock this up to the slower rate of burn from the octane. | ||
| Ed P. (Ebp)
Member Username: Ebp Post Number: 295 Registered: 12-2002 |
I have to say I'm a little skeptical when it comes to differences in brands of fuel. I have certainly experienced the "feel" of better fuel from different places, but I would attribute that more to the filling location itself and the condition of its storage tanks. The reason I say this is because years ago (nearly 20) I had taken a part time job as a fuel truck driver. I can assure you that when it comes to loading the trucks with the fuel it is all done at the same terminals from the same source and there is no difference. All of the big name brand trucks were in line with every other no name company loading from the same exact fill pipes. There was no difference in the products we were recieving. Maybe things have changed now, since that was so long ago, but even then I would hear people having the same conversations about fuel quality. | ||
| William H (Countachxx)
Advanced Member Username: Countachxx Post Number: 3388 Registered: 2-2001 |
I prefer 110 octane when I can get it  | ||
| Ernie (Ernie)
Member Username: Ernie Post Number: 854 Registered: 11-2001 |
The only thing we have here in So Cali is 91 octane. I really don't care, I use what cost less, most of the time I fill up at Costco. However Union76 has about the cleanest gas around. The gas they sell at the pump is more refined than the other companies. The reason companies like Costco can get the gas at the price they do, is because they buy the over production gas. The manufactures have a production amount that gets produced for the dealers. Most of the time they over produce what they need to. So they sell the surplus to independant stations. You get the same gas as form the other stations, you just don't know if it was from Chevron, Shell, Mobile, Unical, etc. | ||
| Brian Kennedy (Kennedy)
Member Username: Kennedy Post Number: 547 Registered: 3-2002 |
Chevron 93 octane. Chevron's Techron is a very good detergent package. I try to get Chevron in at least every other tank; but preferably every one in the case of my Ferrari. Unless you have your car tuned for it, octane above 93 will be wasted/pointless. (At higher altitudes, you won't even need that... 91 may be as high as you'll find.) | ||
| David Karaduman (Ferrariking)
New member Username: Ferrariking Post Number: 19 Registered: 10-2003 |
hey mitch. you may not have found an instant performance advantage.. but running at a high octane will be better for the engine... will it not? | ||
| Mitch Alsup (Mitch_alsup)
Intermediate Member Username: Mitch_alsup Post Number: 1226 Registered: 4-2002 |
When I go to the track, I end up putting in $20 of 104 race gas to go with 3/4 tank of 93. This only lifts the octane rating into the equivalent of 96 octane. Throttle response is ever so slightly better, and the engine noise seems more harmonious. The power output is not altered. Race gas smells wonderful, quite unlike the pump gas that tends to turn my stomache. I have had 104 straight ($80/tank) but no advantage was found over the 96 coctail. | ||
| Vincent (Vincent348)
Intermediate Member Username: Vincent348 Post Number: 1097 Registered: 4-2003 |
91 around here. vincent | ||
| Augustine J. Staino (Azzuro328)
Member Username: Azzuro328 Post Number: 623 Registered: 4-2003 |
I use 93 or 94 octane. There is a Sunoco in Chadds Ford, PA that has a Sunoco GT pump (100 octane race fuel). I don't know if it would do any good, so I haven't tried it. What school are you attending? I'm from Philly. -Augustine | ||
| Michael Palilonis (Mpalilonis)
New member Username: Mpalilonis Post Number: 9 Registered: 9-2003 |
What stations do you like to go to when looking to fuel up your stallion? I know some people trust certain companies, while others don't really care. Also, what octane do you normally get, do you ever treat your baby to some better fuel everyonce and a while, like 100 or 104, etc. ? |