Fuel rating for 03-04 cobras?

[JerNPatti]

What fuel rating does the factory recommend for an 03 or 04 cobra? Is it 91 or 93? :cool:

[julies03]

Premuim Only (93)

[JerNPatti]

That's whatI thought. Someone suggested that it was 91 in another thread. :fryem:

[cobracory]

I am in Canada - and the manual here says 91 octane.
Most gas stations here sell, 87 (regular), 89 (super) & 91 (premium).
Sunoco has 87, 89, 92 & 94.
Pioneer has the 87, 89, 91 & 93 at some locations.

In all cases, the "premium" is the 91 (or 92) octane.
The 93 or 94 is the "superduper premium" octane gas.

[anvrsy red vertble]

The car will run fine with the factory tune w/91 octane. Many states only have this as their premium gas. Only when you start modding the car with timing, A/F, pulley changes, etc. it becomes much more critical to have higher octane gas to prevent detonation. This will destroy an engine in a heartbeat!!

[JerNPatti]

I have been running 93 octane. Maybe that explains the dust like coating on the rear bumper. I thought it was brake dust, but someone suggested my octane was too high and it was causing unnecessary soot to come from the rear pipes. What do you guys think?

[SVTChris]

actually I just looked in the SVT supplement manual and it states to use 91 octane or higher. I also use 93 octane.

[SNAKEYE]

I have been running 93 octane. Maybe that explains the dust like coating on the rear bumper. I thought it was brake dust, but someone suggested my octane was too high and it was causing unnecessary soot to come from the rear pipes. What do you guys think?
Soot on your bumper and octane rating are unrelated. Within reason, soot is a good thing as it indicates a rich mixture, which is much better than a lean mixture for engine survivability. Too rich can foul plugs and result in emmissions testing failure (if you are subject to them). The soot you see could be from operating the engine without it really coming up to full operating temperature, or from putting your foot to the floor often!
I wouldn't worry about it unless you are always leaving a couple of black smoke trails behind you. You might try washing the bumper more often, then it will be out of sight and out of mind!

[JerNPatti]

I rarely run it very hard and I wash it very often. I thought it was brake dust but someone suggested that it might be from running 93 octane and causing too much soot. The way the air is so turbulant behind the car, who knows?

[OKC03Cobra]

No one sells 93 octane in Oklahoma City, so I have to use 91 octane.

[ctaraskewicz]

I am going to be Drag Racing at Raceway Park , Englishtown, N.J. October 9th. I am going to ty a mixture of 94 and 100 octane sold only at the track. I just recieved my car back from SLP Perfomance in Tom's River, N.J. They are new in the Mustang/Cobra market. Traditionally, they were a GM House. They dynoed it at 515RWHP. I will let everone know how I made out.
Daily Driver 2003 SVT Cobra (SLPized)
Weekender 2001 Viper GTS :tmb: :knock:

[JerNPatti]

87, 89 and 92-93 are the only options here. I don't remember ever seeing any 91 octane in NC. :hbomb:

[vger]

WE get 92-94 in Michigan. I took my car out west this year (AZ) and found nothing but 91. My milage dropped and the car was a little sluggish. When I got back to a state that sold 92 or better it came back to life. I also wash my car alot and find little dust on the back.

[SNAKEYE]

I rarely run it very hard and I wash it very often. I thought it was brake dust but someone suggested that it might be from running 93 octane and causing too much soot. The way the air is so turbulant behind the car, who knows?
Well yeah, the top of the bumber is like a shelf and everything settles on it from the turbulent air swirling behind the car.
Try this: stick you index finger into an exhaust pipe, and swir it around 180-degrees. Don't cut yourself on the edge. Got a black finger tip? That's from a rich mixture. Those of us with supercharges don't mind that at all! There may be some on my bumper, but the car is black and gets bathed weekly with (usually) less than 100 miles put on it. So if 'soot' is present, it's miniscual!