View Poll Results: OCTANE - Which gas do you put in your 3IS
I always use 91 or higher.
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259
91.20%
I sometimes use 89 or 87.
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3
1.06%
I always use 89.
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6
2.11%
I always use 87.
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16
5.63%
Voters: 284. You may not vote on this poll
OCTANE - Which gas do you put in your 3IS and why?(merged threads)
#92
#93
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The price difference for me between 87 and 93 is about $.25 - $.30 / gallon - which is not worthy of discussion.
I do have a problem with the $3.xx in front of the price per gallon. :-)
#94
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I will say, it ran no different, made no less noticeable power (Lets face it, the 250 is a complete dog when it comes to accel.) and felt just as sluggish as a 250 normally feels.
I will be putting 93 in my car from here on out since I saw the sticker, as I don't need timing retarded and the car to be any slower than it already is .. but .. just saying, I had no immediate ill-effects after about 250 miles running 87.
#95
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You cheap bastards driving lexus. lol
#98
#99
Driver School Candidate
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I got my ISt this past summer, and still love driving it. I'm just really anxious for a large aftermarket performance selection because I know that this car has lots of potential. Anyway, I happen to swing by this Citgo on York & Irving in Bensenville last night and noticed they still have the Cam2 100 octane fuel available, so I said **** it, and threw $20 in my nearly empty fuel tank @ $6.99/g. Now my car is bone stock under the hood (until next week), not expecting anything noticeable, as soon as I was going through ORD on Irving, WOT, assists off, it was literally quite noticeable in regards to throttle response off the line, the earlier and faster turbo spool, and I can't confirm until I get my Defi boost gauge installed, but it was without a doubt pulling harder than before, and it had to have been boosting more then ever. Just wanted to share. And no, it's not placebo. Now I can't wait to get my parts on the car, even though it goes bye bye in 2 weeks until late march. Have a productive, and boost happy day everyone. #stayboostedandblazed
#100
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Neat! Maybe the extra oomph came from no ethanol in the gas? I believe the engine computer would just adjust things if it was purely an octane boost and no increase would be felt.
#101
Driver School Candidate
Join Date: May 2017
Location: BC
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Hello Club Lexus,
So I've have a is350 F sport 3 and since I got it, I've done a lot of research about which grade to use in my car (regular, mid, premium)
So thing is, the price isn't really the point because its like 5-10 extra more dollars if I were to fill up premium than if I were to fill up mid grade. Since getting the car, I filled up mid grade and sometimes premium.
Question is... if I were keep filling up mid grade, will I damage the car? I even asked my friend who sold me the car and the salesman, they said I can fill up regular grade but I'm just afraid of engine damage (engine knock or w/e). So the solution I came up at the time was to fill up mid grade and sometimes premium.
If the car needs premium grade solely because of performance reason, then I'm going to keep filling mid grade because performance isn't really a big thing for me, but if its going to to cause engine problems... then I will use premium.
So I've have a is350 F sport 3 and since I got it, I've done a lot of research about which grade to use in my car (regular, mid, premium)
So thing is, the price isn't really the point because its like 5-10 extra more dollars if I were to fill up premium than if I were to fill up mid grade. Since getting the car, I filled up mid grade and sometimes premium.
Question is... if I were keep filling up mid grade, will I damage the car? I even asked my friend who sold me the car and the salesman, they said I can fill up regular grade but I'm just afraid of engine damage (engine knock or w/e). So the solution I came up at the time was to fill up mid grade and sometimes premium.
If the car needs premium grade solely because of performance reason, then I'm going to keep filling mid grade because performance isn't really a big thing for me, but if its going to to cause engine problems... then I will use premium.
#102
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Manufacturer engineers who blueprinted and engineered the car say, "Premium 91 or higher only".
Car salesman who pretends to be an engineer says, "Regular 87 should be fine".
Dunno, hard choice.
Car salesman who pretends to be an engineer says, "Regular 87 should be fine".
Dunno, hard choice.
The following users liked this post:
Break2 (07-17-17)
#105
Lexus Champion
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If you say performance isn't a concern, then why even bother with 89? Your car will adjust to the lower octane, but you will not get the full performance of the engine. Supposedly, it won't have any adverse effects on the engine using lower octane, but I wouldn't take the chance (especially if I own the car rather than lease).