i was wondering if its okay to run the car with 90 octane gas, is it going to cause anything? will it harm the engine? I put premium all the way but sometimes i put that mid grade gas. i was just wondering if that will affect the engine and what not...

 

if your stock you should be ok assuming you don't beat your car. On my '03 i accidently put 90 in but i turned the boost down for that tank of gas. I wouldn't reccomend it though

 

It won't hurt it. Knock sensor will retard timing if knock counts are too high. If this happens, the only down side is less performance.

 

Your motor is designed to run on 91 octane. It probably won't harm the motor if you put it in once or twice every 3-4 months and stay out of boost while you've got the watered down mix in there.. but you will probably detonate and you will shorten the life of your motor.

Remember octane rating in gasoline rates the ability of that gasoline to resist knock or detonation. Since you are driving a turbo charged vehicle it is important that you keep the highest octane gasoline available in the car at all times.

Why is it that you sometimes put in 90? Is a higher octane not available or is your wallet running dry? If it's not available, look into alcohol injection. If your wallet is hurting, then you might want to sell the car. No sense in destroying a car because you can't afford to put the right gas in it.

Hope this helps!

-Tim.

 

i'm overseas in england and i can only get 90 octane on base......i could get premium off base but would have to pay ridiculous gas prices. What do you guys suggest?

 

Buy a led knock guage/indicator

 

actually the car is designed for 93 octane per the owner's manual...

i would highly not recommend running 90 UNLESS u have an alky kit. there is a guy in Tucson, AZ that runs alky on his car w/87 octane & it is working very well for him...

 

last i checked, they were designed for 91 because of Cali. 93 is always better though and Mitsu wants to cover their *** with listing the 93 in there.

 

I don´t think you can get anything below 95 in Iceland

 

pay the extra money for the gas, I heard in europe the cheap gas is 100 octane or something like that. I would opt for that stuff. It says premium on the gas cap so I put premium in, nutn else.

 

nope sorry. this is why cars on the west coast run slower than they do back east. bcuz they can't 93, their cars are pulling timing thereby getting reduced power. a west coast car will have to make 25-50 more whp on pump gas to make the same power as an east coast car.

 

i have never ever seen 90 or 91 octane here in south florida. but from what i know from all the evo guys in my area including myself. we all run 93 oct or higher.

 

why worry about a dollar a tank?

 

How much does it cost off base?

 

So go tell the chap who started this thread to drop 87 in his tank and lets see if his motor blows under boost. Lets be serious. In this counrty, ANY factory performance car is designed to run on 91 octane. If they arent, they will blow. They may not produce as much power on 91 which is expected but they are safe on 91. To answer the original question just so this post is relevent, 90 is pushing it just like others said above so dont use it too much or better yet at all.