What gas do ya use???

shelby1

Member
I've been using premium gas since I bought my P5 and the last few fill-ups there seems to be a "hick-up" when I'm going through the revs. Has anyone else had this problem and what kind of gas do ya use?
 
94 is had at any local sunoco and racing gas is every where. I even have a hook up at a local oil comapny. I know a guy that imports 116 or something insane for his Twin turbo audi
 
There is NO POINT whatsoever in using anything other that 87 gas in your P5, UNLESS you have a turbo. None. There is no benefit at all. If it makes you feel better to waste your money, go nuts, but you aren't getting anything from it.
 
Anything But Sunoco...

My wife was putting 87 octane Sunoco in the P5 and had been complaining that it was hesitating and stumbling on acceleration sometimes. I checked the TSBs for Proteges and found that oxygenated gas can cause this. Sunoco pumps in my area have little signs on the side of the pumps that state the gas contains at least 10% ethenol (alcohol made from corn) and is oxygenated.
We switched the P5 over to Unical 87 octane and the hesitation and stumbling has disappeared. Jim
 
Amoco 93

and its not a "waste of money" to use a higher octane...at the very least, it is cleaner!

none the less, i need to use 93 due to the ECU swap!
(thumb)
 
regular unleaded at whatever station in town I happen to stop at.....which means either the EZ-mart or the HEB (local grocery store chain here in texas). they both get their gas from the same supplier...and they are the cheapest in town.....the car runs great and has never missed a beat.
 
JunkPunch said:
There is NO POINT whatsoever in using anything other that 87 gas in your P5, UNLESS you have a turbo. None. There is no benefit at all. If it makes you feel better to waste your money, go nuts, but you aren't getting anything from it.
Actually, even for the p5 89 is recommended in the manual (read!)although it can run 87 just fine!!!!:). 89 is the highest octane that the p5 would need, though. Above that you are just clogging your cats (assuming you are not F/I or high comp).
For stockers, dont waste the time above 89. You're shortening the life of your emissions system.

Run 87 to your heart's content. That's all you need in the p5. 89 just runs a little smoother for those of us who are snobs. :D IT does not extend the life of the motor or lend to significantly better performance.
 
Okay, guys. Let me tell you this from the perspective of a guy who has a B.S. in Mechanical Engineering and an M.S. in Aerospace Engineering and has taken classes on this very thing:

Higher octane gas *only* helps you if you have a high-compression engine (or maybe if you have a truck pulling a lot of weight up a big mountain). Higher octane gas merely has more heavy, long-chain hydrocarbons in it, which makes it harder to ignite. What this does for you is prevent the fuel/air mixture from prematurely igniting from the compression stroke of the piston (this is what is called knocking). If you do not have a high-compression engine, you do not have a need for high octane gas, since 87 (or maybe 89 in some applications) is not going to pre-maturely ignite in our stock/nearly stock protege engines. Octane rating is *not* in any way a rating of how "clean" the gas is - only how "heavy" it is.


Patrick
 
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