Fuel..
TECH Addict
Joined: Nov 2001
Posts: 2,003
Likes: 0
From: Live Oak, FL - in the woods where the creatures lurk.
My car has never seen lower than 92 octane-I would not run 87 unless it was all I could get at the time. Will it run 87? Sure, but performance will most likely suck.
ive never put less than premium in it, whatever octane that is, i just always put that expensive stuff in, and if you really think about it, its on an average only like 3 dollars more to fill the whole tank, i think i can afford an extra $3 for the peformance and life of my engine
Originally Posted by LiquidFire350
ive never put less than premium in it, whatever octane that is, i just always put that expensive stuff in, and if you really think about it, its on an average only like 3 dollars more to fill the whole tank, i think i can afford an extra $3 for the peformance and life of my engine
Trending Topics
Staging Lane
Joined: Nov 2003
Posts: 79
Likes: 0
From: Andrews AFB, MD
As long as your engine isn't knocking/pinging, you can run a lower octane, as it will burn faster and stronger than the higher octanes. I haven't messed around yet with this yet, but I think I will eventually (I've been sticking with the premium so far).
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
TECH Regular
Joined: Mar 2004
Posts: 423
Likes: 0
From: Puget Sound, WA
your PCM will pull back the timing to prevent detonation if you put in lower octane fuel. this means that the car will make less power, note sure about exact numbers, but I heard 10-15 HP on stock f-body.
another thing to consider is that cheaper fuels may have additives that are not good for your engine (faster carbon buildup, shorter cat. converter lifespan etc).
I had pumped cheap (but high octane) gas for about half a year and I started having detonation problems and had to replace one of my cats eventually.
Don't save on the fuel if you plan on keeping you car for a long time.
EDIT: high octane number per se does not make a performance difference unless PCM detects detonation and starts messing with timing - i.e. if PCM keeps the octane bit set to high and you never get detonation, there's 0 benefit to running, say 93 octane as opposed to 91.
another thing to consider is that cheaper fuels may have additives that are not good for your engine (faster carbon buildup, shorter cat. converter lifespan etc).
I had pumped cheap (but high octane) gas for about half a year and I started having detonation problems and had to replace one of my cats eventually.
Don't save on the fuel if you plan on keeping you car for a long time.
EDIT: high octane number per se does not make a performance difference unless PCM detects detonation and starts messing with timing - i.e. if PCM keeps the octane bit set to high and you never get detonation, there's 0 benefit to running, say 93 octane as opposed to 91.
the manual calls for 91 (87) in emergency. With my tuning I'm not sure i'd feel safe with 91, luckly they have 93 in town. I know a lot of people discuss putting in 87 anyway. But you have to remember this is a performance car, if you wanted an economy car there are many alternatives. saving 2 to 3 bucks per tank and having increased detonation and wear just isn't worth it.
TECH Junkie
Joined: May 2003
Posts: 3,050
Likes: 0
From: its fucking cold
The low octane tables will only kick in if the car senses knock due to low octane.
Here's something to think about....but i'll never try (and i know comparing bikes to cars is apples to oranges...).....the fastest factory stock 'Busa's are running 87 octane on their best passes.
You would be just fine if you had to put 87 in your car, and under optimum circumstances you could actually make more power due to less resistance to burning (assuming zero knock conditions)
[flame suit on]
Here's something to think about....but i'll never try (and i know comparing bikes to cars is apples to oranges...).....the fastest factory stock 'Busa's are running 87 octane on their best passes.
You would be just fine if you had to put 87 in your car, and under optimum circumstances you could actually make more power due to less resistance to burning (assuming zero knock conditions)
[flame suit on]
I had a friend try 87 once, a4 stalled, LT's ect. He got on it, started pulling, then heard detonation, it lost most its power and the ses light came on later.
Personally mines never seen uner 91.
Personally mines never seen uner 91.
TECH Enthusiast
Joined: Dec 2003
Posts: 567
Likes: 0
The first LS1 I ever owned (it was a '98), I did not think about the gas, I put in what was cheapest (87). I started noticing the engine was louder, in a bad way, just sounded loud and junkie. Then I found this site and saw a thread about octane. After I drove the gas out I filled it with 91 and it started running smooth again within a few miles, just like when I got it from the dealer. I know this is not scientific, but that was my experience.
TECH Enthusiast
Joined: Jul 2003
Posts: 580
Likes: 0
From: The Republic of Texas
The manual states 91 or higher for good reason I believe. I did run 87 octane for a bout a week or two when I first got it and didn't know. In addition to knocking and pinging, I got lower gas milage. I run nothing less than 91 in it and the milage has improved by abut 2 miles per gallon on average.
The extra 10 or 15 cents more per gallon for a couple of miles more per gallon is a great trade off in addition to not hurting the motor. Also with the LS6 in mine, it has a little higher compression ratio so that makes nothing but higher octane all but a neccessity.
The extra 10 or 15 cents more per gallon for a couple of miles more per gallon is a great trade off in addition to not hurting the motor. Also with the LS6 in mine, it has a little higher compression ratio so that makes nothing but higher octane all but a neccessity.
