Adding extra octane???

Would it be a good idea to have my car on more octane? Because it says that my car should be taking 93, but the highest we have it here is 91. Would it be a good idea to fill up almost 100% octane every few months. I was told that it would help my engine.

I mix the 100 and 91 to run on 93. I feel a slight difference. Of course on road trips it is hard to find 100 octane along the freeway. mike

has it caused any damage to the engine in anyway?

I blend to 93 when the fancy strikes me (very rarely in the winter, if at all). What city are you in? Don't expect a real difference on a n/a engine, but our cars were designed for 93...

100% octane (i.e., toluene) or gas that's rated 100 octane?

IMO, unless you're getting a custom tune for 100 octane, its not worth the extra $. Your ecu can adjust to 91 if it (for some reason) picks up any knocking on those hot summer days.

Interpol: Idk yet wqhich one do you think would be best? Chris(NJ): no i am not getting a custom tune but i was told to do this every few months to clean out my car so it runs better.

I would just find a gas station the sells 100 octane race gas and fill up half your tank with it, and fill the rest up with 91 octane gas. Who is telling you this stuff? Did he explain his reasoning behind how higher octane gas "cleans out" your car? It's completely false.

Toluene (R+M)/2 = 114 Xylene even higher. Lead additive greater still

In summer hot days, I did feel difference on track. not much though. But I always mix 2-3 gallons of VP 100, you can feel you car responds better than 91 only.

So then which store or gas station would be best to purchase this?

Where do you live? how high of the octane do you need? We can get Sunoco 98 and VP 100 in gas station in CA. We can also order VP 109 and Sunoco 104, which is similar price but they are light sensitive so you need to order by 5 gal pail or can.

I live in Los angeles, and what would you recommend for a 2007 Carrera S

If I were you, I would just buy some 2 or 5 gallon pails and go to gas station put some VP 100 in it. Then put 2-3 gallons in it first before refilling 91. Here's list of where you can get VP100: Unleaded Race/Racing Fuel at the Pump in California

No. Not really. Won't hurt anything but your billfold. Best thing you can do regarding gasoline is buy a top tier gas and buy it from a busy station to get the freshest gas you can. If you can't avoid short trips and the increased number of fuel injector heat soak cycles this results in every so often -- once a year? -- use a bottle or two of Techron according to instructions. When the gas tank level gets low (below a quarter of a tank), the gas tank into which you tipped a bottle of Techron into, change the engine oil and filter. Of course arrange to use the Techron a tank or two before the car's engine is due for an oil/filter service. Granted we in CA have to live with 91 octane but it is not the end of the world. Unless you track the car the higher octane gasoline is really not required. Though you can experiment with running more higher octane gas and see what differences you can detect. (I ran my 02 Boxster's gas tank down to the low fuel level warning light was on and put in 6 gallons of 100 octane racing gas (unleaded of course) and could not notice any difference.) Also, since the racing gas costs so much the station may not sell it very fast and thus what it does have on hand may not be fresh. The higher the octane the quicker the gasoline goes from fresh to stale. Sincerely, Rockster.

Rockster Thanks for the tips ..Next time I race against the Cayman S models I am going to try this hey any advantage I can get I will take :dance:

Re: Rockster If you're not having preignition issues with 91 or 93 octane gas the only advantage you will get out of it is that your wallet will be a little lighter. I don't understand why so many people fall for the marketing hype that higher octane gas == more power.

Even better than the lucas fuel cleaner?

Also, would it be a good idea to put in that octane booster ? I've seen it, never tried it and I wonder if it would even do anything in the first place. I'm always running off of 93 all the time.

None of the "octane boosters" you see on the market do anything to increase octane levels in any appreciable manner. The label on the bottle will say something like "increases octane by 7 points " but what they don't tell you is that a "7 point increase" is equivalent to an increase in octane rating by 0.7. So adding a bottle of that stuff to a tankful of 91 will give you an tankful of 91.7 octane gas.

What?!?! lol really? Thats funny I cant believe they get away with that!!! I'm glad I asked! Thank you.

They can get away with it because technically it's true. They just choose to mislead consumers by not defining what a "point" is relative to octane rating. And these things are what, around $10/bottle? Might as well just look for a place that sells 100 octane race gas and buy a few gallons.

Ya I work at Autozone, we sell it, some of its like $15!!! And it's just **** lol. Definitely would go with just race grade fuel, if i was looking for upgraded octane levels then.

Re: Rockster >>>I don't understand why so many people fall for the marketing hype that higher octane gas == more power. I'm not sure who learned this silliness first . . . motorcycle riders or the car folks. Generally the "would it be good to use aviation fuel?" discussion follows the "higher octane equates to better performance" discussion.

See if you can find a place in town that sells gas for boats. That gas has zero ethanol in it, it is unleaded and generally 93 octane. You do get more bang for the $$$ there as there's more energy in a gallon of gas than a gallon of ethanol. Cat and O2 sensor friendly too. The other trick we always used was to go to the airport and get 100 low lead and mix that 50/50 with Amaco premium. If you still have cats this isn't so good, but if you're catelss it works just super and has a near perfect SG. Won't hurt the O2 sensors as long as you don't do it too often. This we did for racing and it works well on very hot days and with high boost. --Ed

Nice I'll have to look into that!

This may sound blunt but I'm not intentionally trying to be rude. I've been in the oil business for 40 years, these cars will run just fine on whatever you get out of the pump. What most of the manufacturers don't tell you, when they tell you you need 93, is that you "need" a research number of 93. Even mid-grade at 89 R+M/2 has a research number of 93 or higher. Typically the research number is 4 - 6 points higher than the R+M/2. Octane "boosters" are ****! And while we're on the subject EVERY retail gas station sells gasoline with EPA and state acceptable additives; Chevron , Shell, Exxon, Racetrac, Quik Trip, BP, etc. It's all made by 2 different companies that just switch some molecules around so each retailer can call it it's own. Save your money for mods, there is nothing magic at the parts store, and put the cheapest gas in you can find, it all basically comes from the same place. All oil companies "exchange" products so at any given time you are getting Chevron gas at a BP station, etc, etc.

Gil, what about additives like toluene with a s**t load of double carbon bonds and an octane rating of 120? The burn rate is slower on higher octane fuels (less knocking), but the amount of heat energy released is a different matter. Any comments on the energy issue? I hear that methanol has an octane rating well above 100 also, but requires a lower air/fuel ratio to burn optimally. What say?

So Gil, do you run 87 or 89 gas in your Cayman?

Well this is getting more and more interesting every post....