Premium vs. Regular
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Premium vs. Regular
I never thought it was that big a deal but it is. Using Premium instead of Regular yields me much better performance with the GXP Bonne. So is the stated 275 hp with Premium only whats is it with Regular? I know the manual said use premium for best perfomance but I did not believe it till now.
Does anyone else have a GXP and notice any difference?
Does anyone else have a GXP and notice any difference?
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From: Fitchburg Ma _ToastedRice_
i always use 91 or 93 on the aurora, usually use 91 on the bonnie unless the wallet is hurting, then the occasional 89 goes in it, i dont notice any performance difference between grades
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From: Pittsburgh, Pa.
i use sunoco 94... actual improvement in acceleration are EXTREMELY subtle, at best... nonetheless, it is a required that some of us use 91+ so we kinda gotta deal with it anyhow
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From: Bloomington-Normal, IL 1997 SE
Originally Posted by toastedoats
i always use 91 or 93 on the aurora, usually use 91 on the bonnie unless the wallet is hurting, then the occasional 89 goes in it, i dont notice any performance difference between grades
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From: Mississauga, Ontario
Fuel grade depends on compression or power adders like a blower or turbo. Most ppl without those items add higher grades of gas because A) it makes em feel better, and higher grade gas has more detergents etc.
I use only 91+ in the Aurora because of its 10.3:1 compression ratio.
I use only 91+ in the Aurora because of its 10.3:1 compression ratio.
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I always used 87 since my first fill up. I always thought the car felt underpowered and slow but sounded great. The combination of the k&n filter and 93 octane makes this car fly and it is noticable alot.
Example I got all the way to 127 mph and it was still pulling hard two days ago where previously with regular I got to 104mph and the engine felt exhausted. I do notice a bit rougher idle now though.
Example I got all the way to 127 mph and it was still pulling hard two days ago where previously with regular I got to 104mph and the engine felt exhausted. I do notice a bit rougher idle now though.
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From: Dallas, Texas
I have a 2004 GXP. I really notice a difference when I use regular (87octane). Dosen't seem to have as much power and runs rougher. I find if I use 89 or 90 (mid grade) it runs fine and has lots of power. I don't think 93 octane improves the performance above the midgrade.
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From: Northern Ca.
I mostly ran low grade in my GXP and it had no problem the night I took it to 140 mph. I never noticed detonation so I saw no need to waste the money on higher grade fuel. I also never ran it with a scanner hooked up to it either so the knock sensor could have done it'* job without me knowing. We ran a couple tanks of premium thru it trying to improve the poor economy and didn't notice any difference in performance or economy. I am of the belief that most people (including myself at times) "notice" a difference in the small things because they know they did the work and spent money. I would love to see someone dyno before and after to find out what they really accomplished.
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I never would put 91 in a GXP why? I mean they say it runs on regular! 91 or higher may be recommended but I know in 2001 they changed the timing so they could run 87! And they can't say you didn't put 91 in it no warrenty left! 
