EmeraldLexuSC3

The station isn't near a race track. nor is it considered "Race gas".
It's offered as a "Super Premium" grade from the three grades they provide:
Super Premium - 100 Octane
Premium - 92 Octane
Regular - 87 Octane

Keith13b

iTrader: (3)

There's always one in every crowd!!!!!! But he needs it!

Use what ever premium gas is available. Its 93 here in Florida. The car is designed (ignition and timing) for premium unleaded...just read the sticker on the gas door. Using lower octane gas won't hurt the car, but you will lose meilage and performance, and emissions aren't guaranteed........same is true putting premium in a car designed for regular. Always add what the car is designed for....as long as its stock or close to.

hansjl

I went through this dilemma with my 95 400 when first I bought it. Read all the threads on this that I could find on CL and elsewhere. Bottom line is I started with 93 and decided to try 89 to see if it would ping and it didn’t. Since my GS300 ran well on 87 with no mileage or performance drop, I decided to try 87 just for one tank to see the effects. Bottom line is that it ran just as well as 93. I drive 70 miles a day and occasionally get on it to play. Haven’t had it ping yet and haven’t noticed any performance changes. You may want to try a modest grade change to see what happen. If you feel comfortable with the performance, pocket the cost difference and eventually buy a toy for your SC or put it toward your insurance.

Research the threads that have been posted here at CL and then make up your mind. Be prepared for different opinions. For me, until I notice any difference, 87 works well. Just my $.02.

anthracitetarga

iTrader: (1)

93 is all for me

EmeraldLexuSC3

I have also done this and notice no changes or difference in mileage and/or performance.

ruki400

The octane rating is really a knock rating. You can use 87 octane and it wont knock.
The only downside is slight power loss which you wont be able to tell.The car
companys tell you to use premium because, thats what they get the advertised horsepower with.

stock300

I use premium in both my LS400 and SC300 but the following article makes me think twice about it.
http://www.usatoday.com/money/autos/...emiumgas_x.htm

EmeraldLexuSC3

Interesting article, It's got me thinking twice also.
I will have to hit this article up with my Father-in law who recently retired from Chevron-Texaco down in Bakersfield.

adidosc

$1.99 for premium in that article? wow...thats pricey...

jet864

Tend to stick with premium, but in the article, he was saying how his wife's turbo car ran just as well on 89 as it did on 91. Now, i know that for forced induction cars when the fuel/air mixture is heated up by compressed air, higher octane is necessary to stop the knocking. Maybe the car she has has a small turbo and low compression, but if I had forced induction, I wouldn't think twice about using anything BUT the highest grade possible. Am I missing something there?

James

jet864

Ahhhh, nevermind, I kept reading and it was explained. My fault.

James

matt7184

Forced Induction necessarily mean that you need to go to a higher octane unless needed, for example grand prix GTPs run on 87 (regular) unless they change the pulley. I've used 87, 89, 91, 93 in my car. It always runs smooth on 93 but it used to run rough on anything else and didnt seem to like to by driven below 2k rpms much, so I kept using 93. Went to a gas station when my car was running on fumes and all they had was 87 and it ran rough under 2k for a lil but then it smoothed out after a few miles but holy **** the thing ran really strong when I was flooring it so I tried to run another 1/4 tank of 87 at another gas station but it never felt that strong like that again. My car seems more picky on where I get the regular gas when I put, sometimes it runs smooth with it, sometimes it idles rough. I just stick to premium for now to be safe.

NRG

im in cali, and i use 91 ($1.79) on my sc400.
race gas is octang 100 and up :P
their's gas station everywhere near me that have these gas, but their's no reason to run it on a stock built car.
the compression wont make good use of the extra octang, and leaded gas is bad for stock injectors

gas isnt that bad now, i remember a few months back when i paid $2.25 for 91.
damn you gray davis

AaronE

Well, around here (SF Bay Area) 87 octane is starting to clear $2, with 91 pushing $2.20. Is there a knock sensor in the SC400 that will retard timing (or is it advance for early detonation?) if the fuel causes the engine to knock? Otherwise, won't engine damage occur?

This is actually factoring into my decision to buy an SC400 vs something like a supra turbo or a 300ZX or (gasp) subaru SVX.

adidosc

why the gasp? i love the SVX's personally....

from what i've read you can safely use 87 in the engine and it will adjust its self to the change in octane, creating a SLIGHT drop in power.