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Um...
Gotta lot of ? huh?
Guess there is nothin wrong with that.
Thats a good ? lets see what any one knows.
 

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I think if you use 87 all the time you will probley be ok because it will learn the low octane. I would not switch back and forth though. Also the first few tanks of 87 I would take it easy until it learns it. Mine will get 93 or E85 if possible.
 

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engines do not learn octane ratings. octane pertains directly to how fast the fuel burns.

Many high-performance engines are designed to operate with a high maximum compression and thus need a high quality (high energy) fuel usually associated with high octane numbers and thus demand high-octane premium gasoline.

The power output of an engine depends on the energy content of its fuel, and this bears no simple relationship to the octane rating. A common myth amongst petrol consumers is that adding a higher octane fuel to a vehicle's engine will increase its performance and/or lessen its fuel consumption; this is false—engines perform best when using fuel with the octane rating for which they were designed and any increase in performance by using a fuel with a different octane rating is minimal or even imaginary.

Using high octane fuel for an engine makes a difference when the engine is producing its maximum power. This will occur when the intake manifold has no air restriction and is running at minimum vacuum. Depending on the engine design, this particular circumstance can be anywhere along the RPM range, but is usually easy to pinpoint if you can examine a printout of the power output (torque values) of an engine. On a typical high-revving motorcycle engine, for example, the maximum power occurs at a point where the movements of the intake and exhaust valves are timed in such a way to maximize the compression loading of the cylinder; although the piston is already rising at the time the intake valve closes, the forward speed of the charge coming into the cylinder is high enough to continue to load the air-fuel mixture in.

When this occurs, if a fuel with below recommended octane is used, the engine will knock. Modern engines have anti-knock provisions built into the control systems and this is usually achieved by dynamically de-tuning the engine while under load by increasing the fuel-air mixture and retarding the spark. Here is a link to a white paper that gives an example: [3] . In this example, the engine maximum power is reduced by about 4% with a fuel switch from 93 to 91 octane (11 hp, from 291 to 280 hp). If the engine is being run below maximum load, the difference in octane will have even less effect. The example cited does not indicate at what elevation the test is being conducted or what the barometric pressure is. For each 1000 feet of altitude the atmospheric pressure will drop by a little less than 11 kPa/km (1 inHg). An engine that might require 93 octane at sea level may perform at maximum on a fuel rated at 91 octane if the elevation is over, say, 1000 feet. See also the APC article.

taken directly from
http://en.wikipedia.org/wiki/Octane_rating
there is alot more, but that sums up the main point. basically the more compression you have, the higher octane fuel you need. it does not 'make' more power, but it is less likely to detonate or spark knock (which decrease power)...
i hope it is designed for a lower octane fuel to save a little at the pump. but if it calls for 93, i will definately put 93 in it. my blue camaro takes 93 or above. the speed shop that built the block tells me that it would run better with 110. hope to try that soon.
 

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If you run less octane than reccomended then the spark table will migrate more toward the low octane table as it senses knock. You will deffintley notice a loss of power.
I guess you could say the computer learns the octane by sencing knock and moving toward the low octane table.
Myself, I would not run 87 in mine. The compression is made for 93 so I think the savings may be null, because I think you would get lower MPG, but I have not tried it myself. I know others that run 87 in there LS1s. If you did the same thing on an older Camaro then it will knock.
 

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Like the owners manual says "warning 91 octane fuel required, use of lesser octane fuel can cause severe engine damage". I concur with Cliff (nice write up) if the compression is that high use premium. True enough with all the sensors on the LS engines the computer will retard the timing and use the low VE preset tune but do some spirited driving and it will still detonate. I'm used to premium prices by now. Been doing it everyday for 6 years now so oh well. If i wanna save gas I'll drive my *cough* Toyota. But when I have my new Camaro I don't think the *cough* Toyota will see much more mileage. Quite sure my Camaro will see 30K miles the first year :lol:.
 

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That's sort'a what I was thinking. With the AFM(hopefully the LS3 will have it) seems though it should balance out the higher cost for gas with outstanding mileage. But I also hope with the rising cost of gas that they (sorry can't think of the word I'm looking for) program it? for 87. But either way, if baby wants 91-93, then baby'll get it.:D
 

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as far as technology has came... with digital tuners and all that out there and the computer compensating for changes via sensors, there should be a switch you could push to automatically adjust timing, a/f ratio, ... and all that for lower octane 'mpg cruising' or a more responsive, powerful high octane tune. i know you cant hit a switch to increse compression or valve timing. but for some trips when you need to go 100 miles and wish to save a little for the trip, you could flip the switch and give up a little power to save 10 bucks at the pump that day. (as long as the adjusted tune will not cause engine wear, or unnessecary damage of any kind)

...not a very high priority option, but to some people would benefit greatly from somthing like that
 

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The camaro engines almost always used high-octane. As all of GM's performance engines do..even the performance 4 cylinders. Would I like a LS3 tuned to work on 87? Sure, I'm a cheapskate. But unless you buy one and retune it yourself..it's not going to happen. :p
Then again, I'd also like a Camaro with the 6.6l Duramax Diesel in it..now THAT would be fun.



 

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I don't mind buying 91 but 93? I retuned my 05 GTO from 91 to 93 and got 4 more mpg from 29 to 33+ highway. The power increase was min. But put it back when 93 started dissapearing. All the pumps I had used went to 91. 93 is hard to find here.
 

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Same here. All I see is 91, and that's what I use for my Vette. I don't mind paying an extra few dollars at fill-up per tank, just so my car is happy on the road.
 

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I think it might be 91 around here..I don't know..I don't use it so I don't care. :p
I did accidentally put premium in my truck once...because that gas station had their layout different than the one I normally used. It ran real smooth for a while. My parents kept making me do errands so I used up all the expensive stuff :(.



 

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I most definitely hope it's not 93 - it's a ***** to find in California (I've never been to a pump that has it). 91, though, would be fine. The price difference is notable, but keeping the engine happy is more important to me. Hell, if I really do follow through with my plans for a VW GTI before the 'Maro, I'll already be used to 91 prices.

I just want to be able to use the 'Maro as a daily driver without having to worry about where to find the right gas.

EDIT: Actually, now that I think of it, they will most likely tune it to 87/89/91, since with 93 they would have a bit of trouble selling it in California, especially LA area, and considering the number of 'Stangs here, I can't imagine GM not wanting to take that over. :D
 

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Yeah that's why any car that needs premium gas is tuned for 91 octane, because the availability of anything higher is spotty.
Here in the Chicagoland area, the availability of 93 octane is pretty prevalent, so that's what my Camaro gets now (BP/Amoco Ultimate only!) and what my 5th Gen will get too. :)
 
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