anyways, i did a search and come up empty handed. my question refers to what type of gas you guys fill your tanks with. i just purchased a 99 ls1 m6 and currently running only premium gas 91 or higher, my question is, with the gas prices as high as they are here in california, can i get by filling my car with 89, or even worse 87? would that hurt something, i'm not really worried about losing performance, since i dont really intent to street race anytime soon... sorry lame question, but very curous... any help would be appreciated.

 

i wouldnt run anything besided 91 gas if i were you. They computer does compensate but its still not great for the engine. I live in california too though i have an lt1 car. Read the manual, it does say 91 octane or higher.

 

haha, i didn't get a manual, damn used cars... lol'

yea', well right now i'm only running 91'... i'm just wondering if it was possible... thank god this isn't my daily dirver... haha

 

Having said that I recommend you use 91 octane, but as stated you can use lower rating. I personally wouldn't do it. You will probably get more pinging under acceleration with 87 or 89 than with 91.

BTW that quote is out of my owners manual, but it should be the same for your car.

 

Definately should fork over the cash for 91. I haven't put anything lower than 93 in since I've had mine...

 

I use whatever I got the cash for. After the purchase of my car last march, money is pretty tight so I buy what every I got the cash for. If I'm low on money it gets 87, after payday it gets 94 But I never had pinging or any problem so far.

KNOCK ON WOOD

 

In over two years (since I bought the car) I've ran 89 once and that was by accident. Every other time has been 92-93. I also only ran 89 once or twice in my '96, which I owned for over three years.

I obviously wouldn't run anything but premium. However, I'm sure that you could run 89 w/o any problems...as long as you're being "easy" on the car.

 

thanx a lot, yea' i kind'a wanted to see what people would say about this, i dont see myself filling my car as of right now with anything lower then 91, but i just wanted to know that if i ever needed to in the future fill with something lower, i wouldn't be in the shop the next day.

just wondering, what do you guys average on a full tank of gas?

i haven't gone through one tank yet, but i can see it should or hopefully will be around 350 miles per tank.

 

I usually go about 280-300 miles on about 13-14 gallons of gas. If you have a m6 you should be able to get about 25 miles per gallon if you stay out of it.

 

I run 87 pretty often. Why burn premium when on a trip or running back and forth to work? I even ran 86 octane last summer in New Mexico and got my best of 30 MPG, and that was with a little 125 mph run. Never had any pinging or rough running.

With the knock sensors a relatively stock LS1 shouldn't ping. The timing just gets retarded. Notice even the manual says you CAN run 87. If you have to go through a sniffer emissions test, running lower octane decreases emissions too.

A lower octane fuel isn't a lesser or dirtier fuel. It just has a lower flash point. Its cheaper because it has less additives to increase the octane or flash point.

 

Mark another one down in the "I run 87 octane" category! As a rule, I've run 91 - 94 in the summer time (especially after I plugged in the Hypertech.........it really needed 94 then) but for the winters and the off-season, I've been running nothing but 87. Hey, it's always $5 cheaper per fill-up, and I go through nearly 2 tanks a weeks, so that's ~$40 extra per month, and right now I'm just doing work and back. Now that the summer is hitting, and I'll probably plug the Hypertech back in and maybe think about going to the track, I'll probably start running something between 91 - 94 again, but I know that 87 won't do harm to the engine.

 

Once my car ran on 87 or 89, don't know because I didn't fill it, but seriously, it runs like crap, no acceleration what so ever, stick to premium.

 

87 octane gas is just fine for your engine it wont cause no damage at all the way engines are made today it wouldnt hurt it at all.by putting premium fuel in your car (93 oct.)it will burn at a higher spark rate giving you better performance.puttin chaep stuff in your gas is fine but premium is cleaner runs nicer and you avoid those high mileage knocks that you might get by using 87 oct.

 

I have run 87 octane in all my camaro B4C's and had NO problems. Total mileage on the three, 293k miles.
I talked to the troopers who drove the cars before me and thewy said they would run both. In colorado I have gotten as low as 85 octane, with NO problem.
I guess its the choice of the owner. Personally, untill I experience pinging, Ill run the low grade.
Just my $.02 worth

 

I usually get about 250 by the time I hit the 1/4 tank mark. I do a lot of city driving, and I average anywhere from 17 to 21 mpg. Now, when I go on road trips and have all highway miles, I get 24-26 mpg.