135 quick clean-up/OptiGuard application

[caddyman]

On my Northstar Cadillacs, premium is "required" (was changed to reccomended) I can run all grades. I usually use 89-93. I do get about 1 mpg better with premum.



The intank "cleaner" are a joke they eat up the netting and filters in your fuel pick-up, only good ones are wherer you hok up a compressed cylinder with a special cleaning mixture, and run until the engine conks out.



I have NEVER used and fuel syste, cleaners of ANY type, and have yet to have a problem.



The gasolines of today are cleaner, and have more detergents and cleaning agents, that will do well when used in conjunction with the recccomended fuel.

[moolman]

I don`t want to start an arguement but just so everyone reading this realizes, premium will not give you better gas mileage. If you think it gives you better gas mileage fine. When you calculate mileage and it came out that premium gave you better mileage, it was just coincidence. Different driving style, more highway driving, etc. There has never been scientific proof that premium gives better mileage.



Think about it. Don`t you think the gas companies would advertise like crazy about getting better mileage if premium did give better mileage. But they never do because it`s not true and the FTC would be all over them.



ALex

[GP Infinity]

Originally posted by DavidB

by David W. Bynon



Many people believe that “premium� gas is the best gas. Not true. Premium simply means “premium price� for higher octane. Octane is a simple measurement for a gasoline’s ability to resist engine knock, a rattling or pinging sound that results from premature ignition of the compressed fuel-air mixture in one or more cylinders.



Most gas stations offer three octane grades: regular (usually 87 octane), mid-grade (usually 89 octane) and premium (usually 92 or 93). The ratings must be posted on bright yellow stickers on each gasoline pump. The misnomer about octane is that the higher the rating, the better or more smoothly your car will run. In fact, premium gas can be bad for your engine if it was not designed to run at a high-octane level.



Although it may seem that the term “premium� or “high octane� implies that more energy is available, premium gas does not produce more energy than regular or mid-grade fuel. The octane grades are designed to accommodate engines with different compression ratios. High compression engines, found in most performance cars, require a fuel that burns efficiently at a higher temperature. That’s what premium fuel does, it burns hot under high compression. In a normal engine, premium fuel does not burn completely, resulting in excess carbon build-up and carbon fouling of the spark plugs. The end result is a less efficient engine that requires tune-ups more frequently. Oh, yeah, did I mention it also wastes money?



The only time you might need to switch to a higher octane fuel is if your car engine knocks when you use the recommended fuel. This happens to a small percentage of cars. Check your owner’s manual to determine the right octane level for your car. Regular octane is recommended for most cars. However, some cars with high compression engines, like sports cars and certain luxury cars, need mid-grade or premium gasoline to prevent knock.

Having said this, David what do you run in your Porshce? I have a `02 Ford Lightning and I have to run premium, even when I drive like a grandma.. so what say you?

Dana

[AkronSi]

SpankyPop, as far as the current gen. Civic Si/Sir, premium is not needed. I know that some people have posted measurable gains in hp on a dyno with premium gas. However, many people, myself included, have noticed a sulfur smell when using premium gas. I can`t speak for the other Honda/Acuras, although I assume that the RSX would also use regular since it shares it`s engine with the Si.

[mrdetailer]

I would experiment. My Subaru recommends premium. I took a long trip and drove over 1000 miles on high octane premium. There was absolutely no difference in gas mileage when I switched back to my regular midgrade.



However, year before I had tried regular and that made a huge difference. Horsepower went way down, and the engine ran rough.

[Vadar]

All you ever wanted to know about gasoline (but were afraid to ask):



http://www.faqs.org/faqs/autos/gasoline-faq/part1/





Dom

1991 Alfa 164S

1975 Ferrari 308 GT4

[don_davi]

I got my 90k service + timing belt done at the dealership this week. I asked one of the service guys how I can improve my gas mileage. I told him I use 87 and he looked at me all shocked.

He asked me if i ever get pinging with 87, and I was like not ever. Then again, i don`t know what it sounds like. So what does pinging sound like? and does anyone know anything about the V6 Engine in the 4Runner? should I be using 87 or 89?



Thanks



Davi



ps. love the forum!

[Neb]

Originally posted by don_davi

I got my 90k service + timing belt done at the dealership this week. I asked one of the service guys how I can improve my gas mileage. I told him I use 87 and he looked at me all shocked.

He asked me if i ever get pinging with 87, and I was like not ever. Then again, i don`t know what it sounds like. So what does pinging sound like? and does anyone know anything about the V6 Engine in the 4Runner? should I be using 87 or 89?



Thanks



Davi



ps. love the forum!

thats interesting that the service guy asked if you got pinging, since most cars nowadays are programmed to lower the timing if the car pings/knocks, so after the inital knock/ping, you won`t be able to hear any because the car has adjusted. Check your manual, it should say what grade gasoline you should be using.

[don_davi]

if the timing is adjusted (in theory), would it hurt my engine or longevity to keep using 87 octane?



Price, I`m not to picky about since my folks own a kwiky mart and I get free gas.



At the same time I rather use 87 if it won`t harm my truck, save my folks some money. BTW, any insights on CITGO gas? hee hee



Oh yah, I don`t have a manual for my vehicle. I`ll ask the dealership later, maybe they have one.



Thanks.



Davi

[Neb]

in theory, it shouldn`t, because your car is detecting the knocking and reducing the timing; but I wouldn`t reccomend you to continue doing it. Car manufacturers do have a reccomended gas for a reason

[stilez]

Back from the dead ...



So I have an Integra GS-R. A lot of engine bolt-ons. I have researched them and for the money, they give me the gains exactly where I want (not sure if this is relevant info, but I`m listing it just in case).



ANYWAYS, my body shop guy told me sometimes he runs 110 low-lead from the airport in a 1:4 mixture (i think) with 1 gal 110, 4 gals premium 93. This 110 low lead is for the small personal airplanes. He claims better performance and a cleaner burning engine with it. He runs it in his 2001 Camaro SS with some bolt ons.



My question is...Are there any advantages to this or is he just thinking he is getting gains?



BTW: I am pretty close with him, I don`t think he`d BS me, but he might just not have the knowledge.

[Ben Z.]

You can definately get gains if you are currently running at the edge of detonation, otherwise its silly. In this case it is a horrible idea if you have stock emmision controls because "low lead" AV gas still has enough lead to kill your cat and possibly O2 sensor.

[imported_garyo]

I agree with Ben.



If you need higher octane because of the modifications and fuel mixtures you are running then get unleaded racing gas. Usually comes in 100-110 octane. As local track junkies where they get their gas. It is usually quite expensive.

[Gonzo]

My manual say to use premium (or the highest octane available). Gotta do that with a blown engine or detonation will reduce it to scrap in a heartbeat. I am even leery of the 91 octane and had my tuner burn me a "Momma" mode on the 4-way for fuel economy on the interstate using 91 octane.

[Glossequation]

Originally posted by don_davi

I got my 90k service + timing belt done at the dealership this week. I asked one of the service guys how I can improve my gas mileage. I told him I use 87 and he looked at me all shocked.

He asked me if i ever get pinging with 87, and I was like not ever. Then again, i don`t know what it sounds like. So what does pinging sound like? and does anyone know anything about the V6 Engine in the 4Runner? should I be using 87 or 89?

Pinging is actually not a good way to describe the noise in that pinging evokes thoughts of a high pitched noise...most detonation sounds more like a slapping noise--that is--lower pitched. Its difficult to describe, but unmistakeable if you hear it.



I have only experienced pinging once and that was when I bought an `87 Toyota 4x4 that had been sitting outside for some time so the gas was old--it was probably the equivalent of 82-84 Octane or thereabouts--due to moisture buildup and the elements. Once that gas burned and I filled the tank, the pinging was gone.



It is my opinion that high octane gasoline (93) is only beneficial in high performance motors or in supercharged applications. Most owners manuals only require a minimum of 87 Octane.



Davi--today`s modern engines are engineered to not need high octane gas...go with 87. People who say there is no difference between 87 and 93 are incorrect--detergent levels are different between them, its just that for most vehicle owner`s the difference is not noticeable.