What's Your Petrol Price? (Don't go to Scam Antionio TX!!!)

Mr Pilkington · Post by **Mr Pilkington** » Mon Aug 04, 2003 11:59 am

Well I find that it gives my car that much more get-up and go. My Highway gas-mileage increases by close to 5% (city drops by about 12% but that’s more my lead implant than gas), and my baby runs just that much smoother. I will agree, I tired it in my old 350 and it didn't a thing for it. But that just go to prove once again Germans do everything better.

Besides If I drop below 91, my car sputters to a crawl, spits then fails.

NicholasDWolfwood · Post by **NicholasDWolfwood** » Mon Aug 04, 2003 2:06 pm

At the station two or three cities away (Northfield, NJ - P&R) is around $1.35 last time I checked

Toecutter · Post by **Toecutter** » Mon Aug 04, 2003 4:02 pm

what exactly is the point of higher octane gas?

I tried the premium gas... and there was no percieavable increase in gas mialage or speed and power in my truck

The higher octane rating means the higher molar concentration of the octane hydrocarbon, which helps decrease gasoline's activation energy for combustion. For high compression ratio engines (9.5:1 or higher), 92 octane or more is a good idea. The less octane in the fuel, the harder that particular fuel is to ignite. Unlike diesel engines that ignite their fuel by compressing the air-fuel mixture to 40 times STP, gasoline engines require spark plugs, since the activation energy for combustion is so high, and the gasoline engines are designed with much lower compression ratios.

Nitromethane and methanol racing fuels are far more efficient, not because they burn hotter, but because they actually burn COOLER than gasoline. A 426 Hemi running nitromethane can have a 14:1 compression ratio, because nitromethane takes less activation energy (in the form of the spark plug igniting the fuel) with respect to STP. So, a guy with a 426 Hemi sporting a Weiand 10-71 blower with 15 psi of boost, and a 14:1 compression ratio can run TWICE the volume of nitromethane as his next door neighbor running 103+ octane gasoline in a naturally aspirated '70 Chevelle SS, with the 10.5:1 compression ratio LS6 454 big block.

Since it burns cooler, alcohol fuels also improve engine performance by keeping the engine block cooler than running on gas. This allows a denser charge of air to be run throgh the intake plenum and into the combustion chamber, giving a higher concentration of oxidizer for the fuel to burn faster and stronger.

In conclusion, the higher the octane, the cooler, more efficient, and easier the air-fuel mix will burn. Spark knock (that pinging noise you hear when you run too little or too much octane) is the fuel not burning completely, or detonating inside the combustion chamber without ignition by the spark plug. For those who haven't figured it out yet, spark knock is a BAD THING!

The best bet is to run 89 octane, because it's the best of both worlds! I found I get better gas mileage in my IROC-Z Camaro (the 5.0L V8 TPI engine) running 89, rather than 87 or 92 octane, it's cheaper than premium, and there's more of it at the pump than 87 or 92, because the manager of the gas station just mixes the 87 and 92 to get the resultant 89. So if the local station is out of 87 octane (this actually happened for a week at one of the old Texaco's around here), there should be plenty of 89 to go around!

kthulhu · Post by **kthulhu** » Mon Aug 04, 2003 4:53 pm

I've noticed there are some differences between gas brands and types, in terms of quality. An '84 Caprice we owned ran best on all premium brands, so-so on major brand regular (Chevron, Shell, Texaco), and was really unreliable on discount/no name gas.

If it were up to me we'd be using biodiesel.

Toecutter · Post by **Toecutter** » Mon Aug 04, 2003 7:37 pm

Part of it is the location of the gas station, and part involves the amount of purification, additives, and processing techniques used by each corporation.

I know at least one Chevron in my town that suffers from a horrible location. Their gas has an incredibly high concentration of water, which is the result of positioning of the underground storage tanks, and improper maintenance. Because this gas station is located right next to the railroad tracks running through town, there wasn't enough room to properly install the tanks to limit condensation.

It's a given cheap gas is going to have some serious side effects to an engine's performance. The more money the gas station corporation has, the more they can spend for throwing in more additives, purifying the crude oil more effectively, and storing it during transport to limit the amount of contaminants. Shell (since they took over Texaco) has been using Texaco's blend of 10% Ethanol, and 2% Oxygen by weight. Texaco and Estby (a small chain of gas stations bought from Texaco, and using Texaco gas) are the best bets for gasoline. Shell loses it's contract with Texaco in about 4 years, so Shell should stop using Texaco gas around then.

Shell's own gasoline is pretty good, but it isn't as good as Texaco gasohol. I've never filled up with Exxon gasoline (because there are no Exxon stations anywhere around my home town), but from what I remember, it's pretty decent stuff.

However, if you want to go for some serious octane without having to stop by the local airport, Shell offers an application and processing fee for a blending card, where you can buy barrels of 100 octane from them, and mix your own combinations of gasoline at their local stations. That would be the best bet for us musclecar nuts with high-compression engines that require at least 92, when we stop in all those crappy towns that only offer 91 octane.

If I had the cash, and I didn't need to wear a gas mask to drive, I'd run nothing but nitromethane. Of course, nitromethane fumes are incredibly lethal, and alcohol fuels have to be pumped out of the vehicle's tank when the car is sitting still, so it doesn't corrode all of the fuel lines. So the best bet for an alcohol fuel is a combination of methanol with high octane gasoline, or if you're talking diesel, using a propane injection system for some extra horses. See the following website for more information:

http://www.turbofast.com.au/

kthulhu · Post by **kthulhu** » Mon Aug 04, 2003 8:40 pm

Arco is some bad gas, as I recall. Usually the cheapest, too.

danielwang · Post by **danielwang** » Mon Aug 04, 2003 9:56 pm

At least it's a name. You should see the Mirastar-Citgo petrol they sell at local KingSooper Krogers, Sam Walton Marts,Costcos, and Barns Safeways. Even Publix might be adding fuel station as well.

When I am in my professional career, I will definitely consider alternitive enrgy options such as electrical hybrid with alcohol or CNG. Ethanol is widely used in Europe as well as solid fuel. No e2fscking cars for me, motorscooters and smegways are much cheaper.

But for now, it's cheap, almost free, used vehicles for me...

kthulhu · Post by **kthulhu** » Mon Aug 04, 2003 10:00 pm

Biodiesel/electric hybrid vehicles, kind of like the Insight, would kick ass. Low emissions, increased mileage, and a virtually infinite supply of fuel.

Toecutter · Post by **Toecutter** » Mon Aug 04, 2003 10:31 pm

Electric hybrids are only efficient in congested traffic conditions. Think about it this way:

The most efficient economy cars in the world can maybe convert 15-20% of gasoline's chemical potential energy into kinetic energy. However, a gas-hybrid vehicle also has the extra parasitic losses due the gasoline engine's kinetic energy being converted into electrical potential energy (the batteries), and the electric motor's kinetic energy. Factor that into your existing 15-20%, and you've got less than 10% efficiency from your starting point.

Hybrids are efficient when it comes to rush hour traffic, because the gas engine is running at 1,500-3,000 rpm, rather than idle. At idle, a gas engine usually has an air-fuel ratio of 8:1 or less, while the ratio under load comes out to about 12:1 to 15:1, depending on the carb jetting, or the EFI system (TBI, MPFI, SFI).

However, the best bet for future automobiles would be methane or hydrogen combustion engines, or fuel cells. Combining hydrogen with oxygen, and then igniting the mixture (much like liquid fuel rockets) produces water vapor as the final emissions, inducing no environmental effects whatsoever. The problem is collecting hydrogen in the first place, which takes some serious power. In order to do this with the least pollution possible would require nuclear and hydroelectric powerplants, and tons more of them than we have now.

As for futuristic aircraft for private use, the best bet would be a ground-effect vehicle, which uses far less gas than a conventional aircraft.

Mr Pilkington · Post by **Mr Pilkington** » Mon Aug 04, 2003 10:47 pm

Bah! Give me dino fuels any day of the week!

I'm a rootin', tootin', and a palootin'