: What Gas Are You Using?



orange110
09-07-08, 08:21 PM
Tho I am still shopping for my first N* SLS, I have a 93 SLS w/ 4.9.
I started using 87 months ago - tho I have a slight "jar of nails" sound from motor on accel, there is really on knock to speak of.
Car is nailing over 20 mpg at 50/50 hwy and city. At $4/gal, I am careful about driving habits.
What are you using - I'm supposed to use premium - what about the N* - do I have to buy 93?

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Submariner409
09-07-08, 08:31 PM
Depends on the Northstar year, your normal driving habits, and personal preference. Read the owner's manual for recommended fuels and alternatives. My 02 is perfectly happy on 87 all the way up to 132 (fuel cutoff at speed limiter).

If your engine now sounds like a jar of nails, go back to 89 or 93. Preignition is no good for any engine.

mighty_quad4
09-08-08, 10:04 PM
99 and older engines are designed to run on premium. 2000+ are designed to run on 87.

running 87 in an older engine is not a good idea and causes pinging. basically what is happening is that the fuel is burning at the wrong point of time in the 4 stroke cycle. use toe correct fuel and itll stop. now, this pinging probably will not harm anything at first, but prolonged pinging WILL cause engine damage. anytime you hear the noise the potential for engine dmg is there.

lastly, i have to say this, dont be cheap. use the correct fuel. it only costs $0.20 more per gallon than 87. filling your car up all the way with 93 vs 87 will only cost and extra $4-$5 depending on what brand of gas you use. compare that to the cost of replacing the engine when something lets go from excessive spark knock. by the way, its an extra $260 a year using 93 vs 87. you could bring your food into work one day a week and probably save more money in the long run.

Ranger
09-09-08, 03:58 PM
The Northstar has a very effective knock sensor so even pre 2000's will run quite well on 87 (been there, done that), not so for the 4.9.

orange110
09-10-08, 08:13 PM
Thamks!!!!
To those who replied - I went back to 93. I already bring my lunch, but what the heck...
Anyway, found a nice 2000 SLS w/ 42K on it I like.
No sunroof, but price is right at $7800.
Well, sonny gets the 4.9 if I buy this, so it looks like he'll have to bring HIS lunch!!!!!!!!!!!!!!!!

Submariner409
09-10-08, 08:38 PM
...........and the 2000 is set up for 87 octane panther piss. (Recommended in the owner's manual.)

alexo1us
09-13-08, 01:32 PM
I only run prem Sunoco gold most of the time for me I find it runs better most of all the range is better (50 to 60km per tank)to make up for the extra 10c ltr