Question: Do I need Premium in my 96 LT1

[gmhowe]

The owner's manual doesn't really say, but under the gas lid it says Premium "Recommended". With Premium (91 octane) here in Phoenix at $4.15 and above ( I know that might be low for some of you folks ), can I run a lower octane and not mess up the engine ?
Thanx
Gordon

 

[Boeingdriver]

The owner's manual doesn't really say, but under the gas lid it says Premium "Recommended". With Premium (91 octane) here in Phoenix at $4.15 and above ( I know that might be low for some of you folks ), can I run a lower octane and not mess up the engine ?
Thanx
Gordon

The Collector's Edition has the LT4 engine, not the LT1. Compression ratio is higher in the LT4.....10.7:1. Use Premium absolutely and try to find it without ethanol. I buy at a Pilot truck stop now because it's the only place I can find 100% gasoline.

 

[stang-etr96]

CE's came both ways .... LT1 (3403 built) or LT4 (2009 built) ....."Premium is Recommend" for a reason, dropping down to a quality mid-grade will NOT hurt the engine. What it will do is decrease your MPG and your performance will fall off. Is the trade off worth it? Thats your call.

 

[gmhowe]

OK so it's GRAB YOUR ANKLES and be happy. Good thing I work at home full time.
Thanx

 

[Tuna]

I've run regular in my LT1 in the past but the car didn't feel the same. I stick with 'premium' - that way I know the motor is giving me all the HP I want when I want it and it feels right.

Since converting it to an LT4, it always gets premium.

 

[gmhowe]

today 13 gallons at $4.19 54.47, ain't it great

 

[John Robinson]

Burning Regular Gas

With the advent of computer controlled ignition GM had the advantage of letting the computer sense things like spark knock or if a tank of gas was not up to standard the computer would automatically reduce the timing advance. Remember that with the compression ratio of our engines the computer was programmed to run on premium fuel. So if you do use regular instead of premium the computer will adjust the timing accordingly.

When I bought my car the dealer had the tank filled with regular. I then used regular for the next tank and my mileage was around 13 mpg in town. I then filled the tank with premium and immediately the idle was better the performance was noticeably better and I got 17 MPG on that tank.

Using todays prices I figured out what the cost per mile was between 13 and 17 MPG

300 miles Div. by 13 MPG = 23 Gal X $4.00/Gal. = $92.00 to drive 300 miles Div. $92.00 by 300 and the cost per mile is .31 Cents per mile to run regular gas.

300 miles Div. by 17 MPG = 18 Gal X $4.15/Gal. = $73.24 to drive 300 miles Div. $73.24 by 300 and the cost per mile is .25 cents per mile to run premium gas.

So I will use premium gas since it actually is costing me less per mile for fuel than regular would.

 

[gmhowe]

Very good analogy
Thanx

 

[B17Crew]

Using todays prices I figured out what the cost per mile was between 13 and 17 MPG

300 miles Div. by 13 MPG = 23 Gal X $4.00/Gal. = $92.00 to drive 300 miles Div. $92.00 by 300 and the cost per mile is .31 Cents per mile to run regular gas.

300 miles Div. by 17 MPG = 18 Gal X $4.15/Gal. = $73.24 to drive 300 miles Div. $73.24 by 300 and the cost per mile is .25 cents per mile to run premium gas.

So I will use premium gas since it actually is costing me less per mile for fuel than regular would.

Thanks for the post, very interesting info.

B17Crew

 

[compyelc4]

John Robinson,

The jump from 87 to 93 in your area is only 15 cents? Around here it is at least a 20 cent jump (10 cents per octane rating level). Now stations are starting to play games with this standard and I'm seeing some stations with a 25 cent jump. Still, based on simple math, assuming 87 degrades avg. mpg by 4 mpg, the numbers still work in favor of 93 octane in your area. Keep going for it.

 

[John Robinson]

John Robinson,

The jump from 87 to 93 in your area is only 15 cents? Around here it is at least a 20 cent jump (10 cents per octane rating level). Now stations are starting to play games with this standard and I'm seeing some stations with a 25 cent jump. Still, based on simple math, assuming 87 degrades avg. mpg by 4 mpg, the numbers still work in favor of 93 octane in your area. Keep going for it.

Actually around here depending on the station the spread between regular and premium is between 10 to 20 cents. The name brands (Shell, Marathon) are using the higher spread and the discount stations are using the lower one. Some of the discount stations actually have 93 octane while the name brands have 91 octane. I do not find much difference between 91 and 93 Octane.:eyerole

 

[gmjunkie]

With the advent of computer controlled ignition GM had the advantage of letting the computer sense things like spark knock or if a tank of gas was not up to standard the computer would automatically reduce the timing advance. Remember that with the compression ratio of our engines the computer was programmed to run on premium fuel. So if you do use regular instead of premium the computer will adjust the timing accordingly.

When I bought my car the dealer had the tank filled with regular. I then used regular for the next tank and my mileage was around 13 mpg in town. I then filled the tank with premium and immediately the idle was better the performance was noticeably better and I got 17 MPG on that tank.

Using todays prices I figured out what the cost per mile was between 13 and 17 MPG

300 miles Div. by 13 MPG = 23 Gal X $4.00/Gal. = $92.00 to drive 300 miles Div. $92.00 by 300 and the cost per mile is .31 Cents per mile to run regular gas.

300 miles Div. by 17 MPG = 18 Gal X $4.15/Gal. = $73.24 to drive 300 miles Div. $73.24 by 300 and the cost per mile is .25 cents per mile to run premium gas.

So I will use premium gas since it actually is costing me less per mile for fuel than regular would.

Most all gas in US is considered as Premium Grade Fuels!!I run Regular 87(Chevron or Texaco) in every one of my cars,Except the Older ones that Don't have a Brain of there own!! My 03 Z-51,My 01 Z06,My 94 LT1 All can Think for there self!! Alright here's a Test for you,If your running 91 Oct or above,Next at about 1/2 tank top off with 89 2-3 fill ups and drive it like usual!!Sure at first it may ping a little when you Romp on it till the ECM has time to reset all the perimeters but it will quit after it tunes it's self to the lower Octane!! Then at about 1/2 tank Top off with 87 next time and drive it like usual!!Then after 2-3 tanks the car or you won't hardly know the difference!!
Then check your Mileage!! The difference you'll really see is the cost your paying at the pump!! Yes,you may see a slight difference in performance and MPG,but it won't be as much difference as to the cost of the fuel!!

PS. Below is a photo of my 94 LT1 6sp car after a 160 mile run to Statesville NC and back,and one of my 03 Z-51 6sp on the home stretch of a 2800 mile run to the mid-west and back with almost No in city driving!!I don't have any of my 01 Z06,butt about 27.5 is the best I can do!!:cool

 

[Toms007]

That's very interesting Junk. I knew that if I ran regular (87) it would ping some, but never thought about the computer having to re-learn for the difference. I think I'll give it a try.

 

[gmjunkie]

That's very interesting Junk. I knew that if I ran regular (87) it would ping some, but never thought about the computer having to re-learn for the difference. I think I'll give it a try.

There Just Like a Women,Tom!! If you spoil them they have to have the Best All the Time!!!!

 

[G Winter]

I have to disagree on the Premium not changing the millage. On my 90 I have kept track of it since I bought it three yrs ago.
If I burn premium for 3 to 5 tanks full and check my millage it will be in the 22 to 24 mpg all around driving.
When I put in regular for that amount of miles I drop to 20 to 22 mpg with the same driving. I can tell seat of the pants diff. between the two.
Ethanol won't even touch my Vette. I had an 89 Riv 3800 V6 , I put in ethanol a couple times and both times my wife came back from driving it and asked what was wrong with the car, it didn't run right. When a women notices it you KNOW there is a diff. She also notices the diff from premium to reg on the vette. I get the same question. Whats wrong with the vette.
I do agree with Junk on the ECM setting the timing for the fuel, that is a fact. But if and engine is optimized for a higher grade of fuel with more advance you will not get as good efficiency when it backs off the timing.
You have to do like John Robinson did and figure the cost. I find that for me the cost is about the same, so I use premium most of the time.

Glenn

 

[gmjunkie]

I have to disagree on the Premium not changing the millage. On my 90 I have kept track of it since I bought it three yrs ago.
If I burn premium for 3 to 5 tanks full and check my millage it will be in the 22 to 24 mpg all around driving.
When I put in regular for that amount of miles I drop to 20 to 22 mpg with the same driving. I can tell seat of the pants diff. between the two.
Ethanol won't even touch my Vette. I had an 89 Riv 3800 V6 , I put in ethanol a couple times and both times my wife back from driving it and asked what was wrong with the car, it didn't run right. When a women notices it you KNOW there is a diff. She also notices the diff from premium to reg on the vette. I get the same question. Whats wrong with the vette.
I do agree with Junk on the ECM setting the timing for the fuel, that is a fact. But if and engine is optimized for a higher grade of fuel with more advance you will not get as good efficiency when it backs off the timing.
You have to do like John Robinson did and figure the cost. I find that for me the cost is about the same, so I use premium most of the time.

Glenn

I agree on the Alcohol,My gas gage quits within 100 miles and the mileage Drops by 3-4 MPG!!(Got some in Missouri that the pump wasn't marked,Had to Techtron the heck out of it to get the gage working again!!) I did see a little drop in Performance at first,but not enough to bother me for the Extra cost!!

 

[Ruby Fan]

Everyone seems to be missing the obvious.....Premium gas didn't go up any higher than regular gas....the price difference between them has been the same, no matter where you live. So in effect you're not paying any more for Premium then you use to pay 2 years ago or when Regular was .99 cents a gallon. Why play around with computers making timing adjustments on a car like a Corvette? Think...when regular was 3.29, premium was 3.59 +/-, now you're paying more for regular then you use to pay for premium....better buy it now before it goes higher

 

[hotshotzny]

Everyone seems to be missing the obvious.....Premium gas didn't go up any higher than regular gas....the price difference between them has been the same, no matter where you live. So in effect you're not paying any more for Premium then you use to pay 2 years ago or when Regular was .99 cents a gallon. Why play around with computers making timing adjustments on a car like a Corvette? Think...when regular was 3.29, premium was 3.59 +/-, now you're paying more for regular then you use to pay for premium....better buy it now before it goes higher

except on the high traffic volume weekends (around my parts) while normally there is only a $.10 difference between grades stations around here seem to add an extra dime or more to the high test pumps on certain weekends (like the one coming up) and what the heck ever happend to the gas wars stations would have years ago now it seems they could care less if the station across the street is a couple cents cheaper, i remember 2 places in particular that would go all weekend playing games with each other and cars would line up to fill thier tanks, i hate to be the one to say this but i think its got to do with who owns the stations now.