What type of gas to use?

[Niteninja01]

Is it really bad just to use 87 rather then the 93? I know my friend has been using 87 since he got his car, he has a 98 gsx 98 gst and a 92 vr4 and he only uses 87. Is it bad to run that?

 

[ilco187]

no, i run 87 all day everyday, i only use premium when the time comes.

 

[rEclipserGST]

WOW. My grandma uses 87. What does it say in the manual? The dash? AND the gas cap? PREMIUM ONLY. You think they put that there just to make you spend the extra $3.00 for a full tank of gas???

If you wanna run 87, buy a honda or at least a non-turbo. SEARCH! This question has been asked before

 

[DSM1G90]

Just that the knock sensor will tell the system to retard timing if there is too much knock when using 87. But if everything is in time and in a closed loop situaton with all of the sensors, then 87 is just as good as 93 and saving tonnage per gallon purchased in the long run.

True, older, 6 bolt turbo systems with the 7.8:1 compression can easily do 87 (like my Laser). But when the higher 8.5:1, 7bolt motors came out with the more higher flowing T-25 turbo to gain an extra 20bhp, then the usage of 91 or 93 ROM was required.

Just that if 87 was used in the 7bolt systems, ECU will retard the spark to prevent knock and thus the power efficency will decrease. You'r simply not getting the most out of the system that it was designed for.

-DSM

 

[Niteninja01]

WOW. My grandma uses 87. What does it say in the manual? The dash? AND the gas cap? PREMIUM ONLY. You think they put that there just to make you spend the extra $3.00 for a full tank of gas???

If you wanna run 87, buy a honda or at least a non-turbo. SEARCH! This question has been asked before

Hey I was just asking a question, you don't gotta be like that about it damn!!

Thanks DSM1G90, yea all I do is just drive the car normally, it's bone stock and I plan to keep it that way besides geting a fmic, bov, cai, and a couple of gauges to let me know what my cars doing.

So I should start to run the 93 then even if I plan to keep the car stock?

 

[Zdrummer15]

I don't know what octane gas is readily available near you, but your car will run fine on 91 and even 89 is ok. When one of my friends let someone else fill his car up once on 87, it made a noticeable, negative difference. It didn't run as smoothly and it definitely affected performance.

Ultimately I would say anything 89 or higher will work just fine, but to get the most out of your car just go with the 93.

 

[blowinsmoke95]

Deff starving performance on 87 just do what the car says and use 93 it will just be one less thing to worry about

 

[Niteninja01]

Ok, it still has a half tank of 87 in her should I run it down till empty or will it be ok to mix 87 and 93?

 

[mistagst]

i use 87 in the winter. no need for power there and saves a few bucks but in 2g's you can def feel a difference between 87 to 93. i say use 87 winters 93 everytime else

 

[DSM1G90]

So I should start to run the 93 then even if I plan to keep the car stock?

You're kinda adding mods that would require the higher octane since your motor is already the 8.5:1 compression ratio with a turbo. But going back to your original question:

he has a 98 gsx 98 gst and a 92 vr4 and he only uses 87. Is it bad to run that?

The VR4 is a 6bolt motor that can get away with 87RON being of the lower compression as long as he hasn't tricked it out. His other two cars (if equipped with the original 7bolt setup, manifold, turbo) really should be doing the higher octane stuff, but his ECU has "detuned" these vehicles down to run 87RON.

You don't need 100 race octane, nor don't dare put in a lesser octane like 85 or below.

DSM

 

[907gs-t]

Here in Anchorage were stuck with 90 octane for are premium.

 

[dylan702110988]

manual says premium only! 91+ is premium!

I remember I let my dad take my old 2g to work, he decided to be a cheap a$$ and put in 87...needless to say my car ran like crap for a week...

 

[One Equals Two]

Yeah, depends on altitude and a lot of other things.

In Utah, it's 85 for regular, 87 mid grade (I used in my Turbo Chyrsler before just fine 7.5:1 compression ratio) and 91 for premium.

But seriously, like, I know you think it's a lot but really....it's not man. Just go premium. I pay like $2.80 to go premium per tank. It's really just a trip to McDonald's.

 

[fstfcs]

around here 93 or 91 is 20 cents more.

that's a dollar more for every 5 gallons. so approx a little over 3 dollars for a full tank more then 87.

They tell you to use premium for a reason. The car was factory tuned and made to run it.

Octane is not a measure of the amount of energy in gasoline - rather, it is a measure of how well the fuel resists preignition, also known as detonation or 'knock'. Detonation is very hard on the engine, and must be avoided. The DSM cars incorporate a knock sensor specifically for the purpose of detecting knock. Higher-octane gasoline resists knock better than lower octane gasoline.

read more here

[Club DSM] Why do these cars require premium fuel? Is it worth it?

 

[ilco187]

110 is my premium

 

[Niteninja01]

Ok I'll start runing 93 once I need to get gas. I just hope not runing it hasn't messed anything up.

 

[DSM1G90]

Yeah, depends on altitude and a lot of other things.

That altitude thing used to be a big factor (since, in SLC, you're up there at 4300ft) and one would have to change timing, carb jets, et al for such occurances.

Now, there is a barometric device called an Ox sensor that senses oxygen levels in the exhaust which communicates with the ECU to determine how much fuel to be used for the proper A/F mixture.

I just hope not runing it hasn't messed anything up.

Nah, you haven't messed anything up. You might get better performance though going with 91/93RON since the ECU recognizes the oxygen levels changing, getting no signals from the knock sensor and will allow the timing to increase back to the required settings.

Good luck - DSM

 

[Beemer92]

I have some mild mods on my talon. I usually run 93 octane and throw in some octane boost once a week, sometimes more. But the cheap gas here in Illinois is 89 octane with 10 percent ethanol. My talon runs fine on it.

 

[Niteninja01]

Cool thanks for all the help on here guys!!!!

 

[OEM]

Just don't expect an instant difference once you put premium in it. After a few cycles the ecu will pick up on the premium.

 

[Jeff99GS]

If you drive OFF boost all the time it will be fine. But If you are heavy on the skinny pedal you're going to BLOW that engine from KNOCK and DETONATION.

 

[Niteninja01]

No I'm very easy on the car, I'm not going to drive it hard untill I get my timing belt done, I don't want nothing to happen.

 

[MrBoxx]

Can anyone give me a reason to NOT run premium fuel in a turbocharged performance engine?

Cost should never be a reason, by the way. You drive a DSM. You should know how to take care of it correctly, even if that means spending an extra dollar at the pump every week.

 

[DSM1G90]

Key word here is "performance" which I do agree: If your going to hit the strip and get the best timeslip readings you're gonna muster out of a beast of a 4G63 setup that you created, you'd better run 100 low lead av fuel in that thing since you're gonna shove 50 plus PSI in that combustion chamber and "brother, it had better not knock on you!"

But, if you're going to do simple DD freeway, driving it for 14k miles per year on the freeway, driving with a 6bolt, 7.8:1 compression motor with a stock turbo (b16g) setup and barely blip it open only for needed reasons, why shove in fuel that cost's 20 cents more per gallon than standard 87RON and you can still get the thrill of a good boost when needed..and your motor hasn't complained what so ever?

..and I can still muster a good 28mpg in doing so .. as long as the turbo remains in check from going into boost...

-DSM

 

[JusMX141]

I know my friend has been using 87 since he got his car, he has a 98 gsx 98 gst and a 92 vr4 and he only uses 87.

Rule #1 in life: Always do what your friend does instead of what the car recommends because your friend is a f*cking genius.


Use premium. If you can't afford the gas, you shouldn't be driving the car.

....But when the higher 8.5:1, 7bolt motors came out with the more higher flowing T-25 turbo to gain an extra 20bhp

Ummm....

Yeah. I don't even need to reply to this one.

Here in Anchorage were stuck with 90 octane for are premium.

That's the definition of irony. Alaska's sitting on enough oil to fuel the USA for the next 40 years, and you can't get higher than 90 octane there. !