I have, what I think, is a stock tune in my 01 GT Vert. The strange thing is, it really likes premium fuel. The car doesn't seem to ping or run horrible on 87, but after a few back to back comparisons, the car runs better, even the exhaust sounds a little better when running premium.
I thought the stock tunes on these cars were made to run on regular so running a higher octane fuel wouldn't really make any difference. Has anyone else experienced this? I guess its possible that it could have a tune in it ( I bought it from a dealership and it had subframe connectors on it). But I doubt it.
now don't quote me on this but i thought i was told or read that running anything higher then 87 on the stock tune would serve no further gain and might even do more harm then good. since its just as clean as the premium, all your gaining is the higher octane value which its not tuned to run on...like i said i could be wrong but just something to think about.
Yes, I understand spark timing/detonation/compression and how the octane rating of fuel relates to the burn rate....
but....
I notice my car runs like a different animal when using higher octane fuel. I haven't hooked up the G-Tech meter to compare stats (which I might do), but I have noticed just by driving it. Is there a way to tell if the computer has been tuned by using a scantool? Does anybody know the stock timing specs so maybe I can compare?
Yes, I understand spark timing/detonation/compression and how the octane rating of fuel relates to the burn rate....
but....
I notice my car runs like a different animal when using higher octane fuel. I haven't hooked up the G-Tech meter to compare stats (which I might do), but I have noticed just by driving it. Is there a way to tell if the computer has been tuned by using a scantool? Does anybody know the stock timing specs so maybe I can compare?
doesn't hurt to run higher octane..just a waste of money. If you have 87 and get on it and you don't get any detonation i would say you don't have a tune other then stock on it. if it does then you might. if its a stock tune then the extra performace is in your head lol
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3.73 gears, BBK cai,BBK Throttle body and plenum, BBK long tubes with x-pipe, flowmaster 40's, steeda pully's, steeda's tri axle shifter, diablo predator, spec stage 1 clutch,spec aluminum flywheel, crossed drilled rotors front and back, ford racing springs
If the car has some mileage on it, carbon build-up on the pistons and valves from running cheap gas can effectively up your compression ratio, making it to where it likes higher octane.
I used to have a stock '86 Monte Carlo SS 305 that would ping it's butt off because it had 300k miles on it, and had so much crud on the valves and pistons. Put 93 in it, and it stopped pinging.
If the car has some mileage on it, carbon build-up on the pistons and valves from running cheap gas can effectively up your compression ratio, making it to where it likes higher octane.
I used to have a stock '86 Monte Carlo SS 305 that would ping it's butt off because it had 300k miles on it, and had so much crud on the valves and pistons. Put 93 in it, and it stopped pinging.
Correct. If the car has ping, it might react to higher octane gas and STOP pinging. If it doesn't ping (which it should not if it is in good shape) it will do just fine with Reg gas.
And YES, this has been discussed to death.
In general terms unless modifications have been made (higher compression ratio, for instance, which of course CAN come from lots of carbon sitting around) to the engine - or a TUNE with additional timing that demands higher octane - there is no performance gain from running it.
And no, the cars do not "sense" the extra octane and bump up their own timing or modify their own air/fuel mixture to extract the optimum power from the gas, whether it be race gas or premium.
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tripleblack
"You can never be free until you let yourself go."
I actually lost milage when running 93 octane. And this whole ethanol thing, its bu!! Sh!t, I understand it may be better for the enviorment but its not worth the loss in perf. and fuel economy.
Honestly. Your wasting money, buy regular. I think the higher octane=higher power is in your head. Sometimes I like to think all the money Ive put in my car had given me some HP or TQ gains and race around. Then I realize its just a 96 with a coolant leak and tore up convertible top. Oh well.
Running 10% ethanol in gasoline (which is now popular with most oil companies and many state EPA's) REDUCES gas mileage by 2%.
And 10% ETHANOL mix fuels do NOT benefit from the huge government subsidies that drive down the cost of E85 so that the corn industry can make money selling subsidized ethanol.
And ethanol pollutes just as much as gasoline, it just does it DIFFERENTLY. The current standards are based upon the assumption that gasoline is being burned - so the tests look for the usual pollutants FROM gasoline, and the standards regulate THOSE pollutants. Ethanol has been found to generate essentially the same AMOUNTS of pollutants, just different ones. As soon as it becomes politically correct to focus on this, ethanol will become just as "evil" as gasoline.
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tripleblack
"You can never be free until you let yourself go."
Stock tune likes 93 octane? 
