Premium fuel article... interesting!
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Touchdown038
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My dad has a 98 accord v6 SCC(i think) dynoed the car and it actiually had more power on regular.
Car and driver also had an interesting story once about premium gas. They used a honda CRV. There were no significant HP differences between Premium and Regular.
They then advanced the timing on the CRV and noted a significant increase in mileage. At the time the articl was written the increase in gas mileage was enough to pay for the premium.
Also that article leads the average reader to believe that all modern cars have these "super" knock sensors. That just isn't true. Also when they say that the cars computer is constantly running up to the edge of detonation (i'm assuming with timing) they are mistaken. Otherwise putting a tank of premium in an accord would make it faster (more timing exc). Modern ECU's are definately capable of amazing things but the auto maker isn't going to spend the extra devlopment costs just so joe blow who runs premium in his caravan will get better HP numbers.
Car and driver also had an interesting story once about premium gas. They used a honda CRV. There were no significant HP differences between Premium and Regular.
They then advanced the timing on the CRV and noted a significant increase in mileage. At the time the articl was written the increase in gas mileage was enough to pay for the premium.
Also that article leads the average reader to believe that all modern cars have these "super" knock sensors. That just isn't true. Also when they say that the cars computer is constantly running up to the edge of detonation (i'm assuming with timing) they are mistaken. Otherwise putting a tank of premium in an accord would make it faster (more timing exc). Modern ECU's are definately capable of amazing things but the auto maker isn't going to spend the extra devlopment costs just so joe blow who runs premium in his caravan will get better HP numbers.
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Stoneage_Turbo
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Just about anything
i dunno cold , its a turbo , id think on a hot day youd dentonate on 87 , but i dont know much about subaru turbos , id say to do it, timing and boost would have to be trimmed back like i say tho my turbo experence is sevrely limited, esp in hot climates
its too bad i have to use preimum , the savings would be great
my caddy has has to have premuin due to the fact it doent have a knock sensor , the computer flys blind when it comes to ping , it doesnt know if its pinging or not so the timing cant be changed around to the fuel requirements , instaed it uses the egr system to remove excess unburned fuel as told to the ecu by the o2 sensors , and temp signals from air intake temp and coolant temp senors,in turn crudely trying to controll ping that the computer knows nothing about. a stupid way to go around haveing a knocksensor , but a good way to make sure caddy owner only use premium so the oil companys stay happy
cant wait to grab another G20
its too bad i have to use preimum , the savings would be great
my caddy has has to have premuin due to the fact it doent have a knock sensor , the computer flys blind when it comes to ping , it doesnt know if its pinging or not so the timing cant be changed around to the fuel requirements , instaed it uses the egr system to remove excess unburned fuel as told to the ecu by the o2 sensors , and temp signals from air intake temp and coolant temp senors,in turn crudely trying to controll ping that the computer knows nothing about. a stupid way to go around haveing a knocksensor , but a good way to make sure caddy owner only use premium so the oil companys stay happy
cant wait to grab another G20
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Mayhem_J30
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lessthanjakejohn
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Repo Man
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Cold_Zero wrote:My previous comment had a hit of sarcasm that you all missed.
Hehe, I didn't miss it. Maybe it's because I've known you for fifteen years??:D
And hell yeah! I ran 87 all the time in my Turbo Buick. It made TONS of power with no detonation that way. I have no idea why the factory would recommend premium??? :thinker
Written by someone w/o a clue that needed a story and quoted selectively.
Many 87 rated engines when older build up deposits in their combustion chamber effectively increasing comprerssion ( and sometimes providing a pre-ignition source) that may make a higehr octane fuel essential to saving the engine.
Fred...
Many 87 rated engines when older build up deposits in their combustion chamber effectively increasing comprerssion ( and sometimes providing a pre-ignition source) that may make a higehr octane fuel essential to saving the engine.
Fred...
Octane isn't a rating of the quality of gas or anything, it is simply that the higher the octane the higher it can withstand detonation. That is all.
if your car doesn't ping using 87 octane, then run 87 octane, there is no advantage to running anything higher. Running higher octane in a car that doesn't need it isn't like a treat for your car or something. It won't hurt it either, just your wallet, but there is no point.
if your car doesn't ping using 87 octane, then run 87 octane, there is no advantage to running anything higher. Running higher octane in a car that doesn't need it isn't like a treat for your car or something. It won't hurt it either, just your wallet, but there is no point.
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Mayhem_J30
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sims wrote:Octane isn't a rating of the quality of gas or anything, it is simply that the higher the octane the higher it can withstand detonation. That is all.
if your car doesn't ping using 87 octane, then run 87 octane, there is no advantage to running anything higher. Running higher octane in a car that doesn't need it isn't like a treat for your car or something. It won't hurt it either, just your wallet, but there is no point.
If using a higher octane in a motor designed for 'regular' won't it adversly effect the output and gas mileage? Seems like with out the proper timing advancements the optimal burn for the higher octane fuel will never be achieved. Is this correct?
not really, I’ve heard people talk about how running higher octane then needed can eventually cause carbon buildup in the engine. But I don't know that there is truth behind that, and even if there is, a few hard runs keeps it clean. Either way there is no advantage. all gas is the same, octane is added to prevent detonation, the more octane, the more the gas can resist detonating.
the simplest way i can think of explaining is would be, think of a turbo setup with an intercooler. assume the turbo setup runs at 10 PSI. if the intercooler(and engine) can support the 10 PSI, there is no need to upgrade your intercooler. it won't hurt anything to get a better intercooler, but without increasing the boost, there is no real point.
the simplest way i can think of explaining is would be, think of a turbo setup with an intercooler. assume the turbo setup runs at 10 PSI. if the intercooler(and engine) can support the 10 PSI, there is no need to upgrade your intercooler. it won't hurt anything to get a better intercooler, but without increasing the boost, there is no real point.
The Octane rating used on gasoline is just a comparison of the particular Gas against pure Octane. Seeing as real Octane, a substance extremely reistant to pinging, is extremely expensive, there is none in gas. Instead, the numerical value assigned to a type of gas is the theoretical equivalent of percentage in pure Ocatne.Example: 93 Octane rated gas is theoretically as resistant to pinging or knocking as 93% pure octane.
For useless info, the formula for getting the Octane Rating (R+M/2) is just an average of two tests. The first test, called "Reasearch" (R), runs a motor at about 600rpm. This resembles a low knock scenario. The second test, "Motor" (M), runs at higher RPM, resembling a higher knock-danger setting. These 2 ratings are averaged to give you your convenient Octane Rating. Don't ask me why they named the tests what they did because I honestly have no idea....
For useless info, the formula for getting the Octane Rating (R+M/2) is just an average of two tests. The first test, called "Reasearch" (R), runs a motor at about 600rpm. This resembles a low knock scenario. The second test, "Motor" (M), runs at higher RPM, resembling a higher knock-danger setting. These 2 ratings are averaged to give you your convenient Octane Rating. Don't ask me why they named the tests what they did because I honestly have no idea....