ive tryed searching and cant find anything, does a 2000 camaro z28 LS1 have to run high grade fuel? ive been running 93 octane fuel just to be safe, but with the gas prices the way they are its been killing me putting in premium. the car is completly stock, ill only put in the lower stuff if its not going to cause and problems or pinging, just wanting to know so i can save a little $, thanks.

 

I'd run the premium fuel. You are only saving a couple of bucks per fill up if you were to use the regular grade.

 

yea thats what i fgured with a 10.1to1 compression ratio, but was just conferming, thanks

 

Although your LS1 engine will run on 87 octane, the knock sensors will pull timing and you'll loose performance. The Owners Manual states to run preminum fuel.

From Shoebox's site, a quote from the 2000 Owners manual:

If you have the 5.7L V8 engine (VIN Code G), use
premium unleaded gasoline rated at 91 octane or higher
for best performance. You may use middle grade or
regular unleaded gasolines, but your vehicle’s
acceleration may be slightly reduced.

 

91 or higher, yes. Putting in lower grade fuel will likely cause your mileage to drop, negating any cost savings you'd see. The engine is capable of running on low grade fuel, but the engine computer will scale back performance to compensate.

 

No it won't. I got my best of 30 mpg on 86 octane, and that was cruising at 85 mph with a nice 120 mph sprint thrown in on the tank. 28 mpg is the best I've ever done with 93 octane w/out any high speed sprints.

Lower octane does NOT mean it is a lesser fuel. A lower octane number just means it'll burn more readily, which mean it burns more complete when compared to a higher octane. How would that reduce your milage?

 

I don't think that octane is a rating of how readily a gasoline burns but its resistance to pre-ignition, ie the higher the octane the more resistant it is to pre-igniting, which is important in higher compression engines as higher compression ratios can cause pre-ignition (pinging)

But of course I could be completely wrong about all of this

 

It's a measure of the ability of gasoline to resist detonation. Read here for the long version: http://www.superchargersonline.com/content.asp?id=105

 

Detonation is premature ignition which is the beginning of combustion. Premature ignitions means the fuel will start combustion at a lower temp or pressure (ie with less effort or "easier"). Therefore it takes less to get it to ignite which means it burns easier.

Lower octane fuel also burns more complete and decreases emissions. It sure isn't going to decrease your gas milage.

 

If I recall the specs right they say if your compression stroke is over 10:1 then you should use a higher octane than 87, but don’t quote me on that number as it is off the top of my head and quite possibly could be a little higher


Personally, I rotate tanks one 87 then one 93; however, my reason is not soley the octane as my car runs fine on 87, but I actually do it because Shell puts in a pretty decent engine detergent in their premium.

 

Using that logic, why aren't we all still running the 40 rated octane fuels we had back in 1920? Why are current race fuels 100+ octane?. Wouldn't race engines want fuels that are the easiest to burn giving the most complete burn in order to extract the most power?

 

Because the higher octane fuel isn't what is giving more power. It is the conditions/design of the engine ie. more compression, advanced timing, forced induction etc.

To be able to use these conditions which do make more power we need a fuel that doesn't ignite or combust as readily or that is more stable when in these environments.

The point here is that if the engine is not designed to run on more octane (lower compression etc) then you will see no improvement in milage or performance by running high octane.

 

i have a 2000 Z28 and it doesn't like the lower octane gas. i put 87 in it once and that was it. i said never again. the car ran like ****. 91 is ok but i only put 93 in it now i tried all the octanes one and found the car runs best on 93

 

If your car doesn't retard timing with 87 octane YOU WILL BE FASTER with 87.
If your car does knock with 87 octane you will be slower.

I came from a boosted car so I know ALL ABOUT knock retard and gas grades and what they do.

You want to run the lowest octane fuel you can without knocking. That's where you'll get the most power.

 

A lot of bad info.... octane is not related to fuel burn speed, or to energy content. It is simply a measure of the fuel's ability to resist detonation by NOT producing the by-products (end gasses) that will auto-ignite. It would be interesting to see some supporting documentation to the claim that low octane fuel "burns more complete (sic)".

Here's the best reference source on the 'net. Read Section 6 (in part 3) in particular.

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