Anyone using regular or mid grade in your SC 400.

Reason I ask is I just picked up my 93 SC 400. I have had a 2005 LS 430 for 4 years. It has 140,000+ on the clock and for the last 80,000+ miles I have run only regular and the car has performed perfectly. I realize I probably lose some hp and performance but the way I drive it hasn't been noticeable.

 

I have always used mid grade and have had no problems.

My mechanic told me i could even use regular but I dont want to cheap out that much.

 

https://www.clublexus.com/forums/sc-...-your-car.html

 

If you use a lower grade your mpg will decrease.

 

guys, you only saving like 4-5 dollars per fill....probably

 

My car shakes more and the gas burns faster than 91 gas. So overall you're better off getting premium gas, that might just be me though :|

 

I dont know , i experimented with different grade fuels and i simply dont notice anything ,ive never used 87 ,,,but i ont feel a difference beetween 89 -91-94

I honestly dont belive mid grade is doing any harm, but do fill up with premium every so often,and i dont do it out of cheapness, the general consensus seems to say its just not necessary

 

*sigh*

No, the engine has not grenaded from the lower octane. What it has been doing those entire 80k miles is running on the ragged edge of knock. The only thing between you and chipped ring lands is the knock sensor. That retarded timing has meant higher EGTs for your car's lifetime, stressing components more than necessary.

The knock sensor lets you use low grade fuel in emergencies, not all the time because you want to save the whopping $2 per tank it takes to run premium.

 

there are a lot of misconceptions about low grade fuel..gas is gas is gas..this is how I understand it..it's all the same ~114,000 BTU's. the differences lie in the duration of the flame front..a lower grade fuel does not burn as long as a higher grade of fuel..93 will burn longer than 87. The lower the octane of fuel, the less spark advance the engine can run, this is noticed in a slight decrease in performance unless it's a 2010 Chevy Camaro SS (my girlfriends) which ran WAY better, like 25% better on 91. A higher octane allows the engine to run a more advanced timing map increasing the engines efficiency and lowering exhaust gas temperatures by decreasing knock. that's all i can think of, but you really do get what you pay for when it comes to fuel.

 

Higher octane burns faster lol.

 

it acually burns slower

 

our ecu's are not very aggressive form the factory. you won't be on the edge of knock, but it may feel a little more sluggish though. mid grade is what all my toyotas/lexus's gets except for anything with a turbo gets premium.

 

I use always use premium because of a better gas mileage and engine responds better, and burns cleaner gas slower with more power to the engine without hesitation that u get with 87 octain

 

This is actually a fair question... I'm possibly moving to a section of the country where Premium isn't really premium. According to my homie (haven't done any research yet, cause I wanted to ask my fellow gearheads first), Iowa's mid and top grades have a heavy concentration of ethanol (like over 10%). He has a Chrysler 300C which he runs 87 through, because otherwise the ethanol in the higher grades causes his engine some issues...

SO, here's the question for those of you living in that area and who have experience with this gas. What do you use? Any station that's better than the others? For the SC owners, any noticeable problems with running the higher grades?

At this point, price really isn't an issue. I knew I'd be spending more on gas when I bought the SC; I just want to make sure if I can't get the gas I need, I'm not looking at a total meltdown of my internals.

 

There is no difference from one brand to the next.
The top tier gas producers are manufacturers who have introduced a detergent into their blend of gasoline. These top tier gas producers were asked by GM, BMW, Toyota, Audi, and VW to formulate a detergent as the current EPA minimum detergent requirements do not go far enough to ensure optimal engine performance.

Since minimum additive performance standards were first established by EPA in 1995, most gasoline marketers have actually reduced the concentration level of detergent additive in their gasoline by up to 50%. So gas used to better 15-20 years back when

Even if you used Walmart gasoline, which is not a top tier product, you could still use the blue bottle of techron like every 10,000 miles or so to get the same results.

There is no difference between the major brands of gas. Truth is you don't know where the gas you buy is coming from Chevron, Texaco, Shell, or BP. It all comes from the same well in a ground or in a pipeline, on a ship that comes into port, get distributed by wholesalers, and then retailed to where you pump your gas. Your shell station could be selling you a chevron blend. You dont know.
Gas Stations are sold whatever the wholesalers get at the port terminal. it could their blend or someone elses.