few questions on octane and additives
03-01-2014, 01:29 PM
#1
2nd Gear Member
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Location: USA
Posts: 371
few questions on octane and additives
A while back people told me that using higher octane does more bad than good ie: preignition detonation and pinging. They also said additives do nothing.
Been wondering though why do gas stations even sell 89 octane then? If most cars from factory require 87, and boosted cars are 91 or 93... so is that only true for newer cars? Does than mean 1990's and 1980's cars will benefit from higher octane?
My mechanic friend recommended chevron with techron fuel system cleaner with each oil change, but if additives are bad then how else can u burn off the carbon build up and etc? Or is that only helpful for older cars?
As for oil additives they say they are good for cars that use up a lot of oil.
Been wondering though why do gas stations even sell 89 octane then? If most cars from factory require 87, and boosted cars are 91 or 93... so is that only true for newer cars? Does than mean 1990's and 1980's cars will benefit from higher octane?
My mechanic friend recommended chevron with techron fuel system cleaner with each oil change, but if additives are bad then how else can u burn off the carbon build up and etc? Or is that only helpful for older cars?
As for oil additives they say they are good for cars that use up a lot of oil.
Last edited by RazorGT; 03-01-2014 at 02:07 PM.
03-01-2014, 03:37 PM
#2
5th Gear Member
Join Date: Jun 2005
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Posts: 3,319
Octane & additives
Here is my opinion. Higher octane than your car needs will not hurt anything, but if you're not tuned for it, it will not benefit you either. I went to school for gasoline & diesel mechanics and that is what I was taught.
As for gasoline additives, from what I've heard most of them are of little if any value. I heard a lot of them are mostly kerosene, which while not hurting anything also won't benefit you. I do think there is one that is beneficial, and that one is Chevron Techron. I know Ford recommends it. I use a 20 oz. bottle at each oil change-5,000 miles. I have yet to have a fuel system problem of any kind.
As I said these are my opinions.
As for gasoline additives, from what I've heard most of them are of little if any value. I heard a lot of them are mostly kerosene, which while not hurting anything also won't benefit you. I do think there is one that is beneficial, and that one is Chevron Techron. I know Ford recommends it. I use a 20 oz. bottle at each oil change-5,000 miles. I have yet to have a fuel system problem of any kind.
As I said these are my opinions.
03-01-2014, 04:41 PM
#4
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Location: Pennsylvania
Posts: 352
The new 5.0 recommends premium(91) to get optimal performance but 87 is acceptable. You lose some HP and TQ using lower than premium, though.
03-01-2014, 04:45 PM
#5
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Join Date: Jun 2013
Location: Pennsylvania
Posts: 352
A while back people told me that using higher octane does more bad than good ie: preignition detonation and pinging. They also said additives do nothing.
Been wondering though why do gas stations even sell 89 octane then? If most cars from factory require 87, and boosted cars are 91 or 93... so is that only true for newer cars? Does than mean 1990's and 1980's cars will benefit from higher octane?
My mechanic friend recommended chevron with techron fuel system cleaner with each oil change, but if additives are bad then how else can u burn off the carbon build up and etc? Or is that only helpful for older cars?
As for oil additives they say they are good for cars that use up a lot of oil.
Been wondering though why do gas stations even sell 89 octane then? If most cars from factory require 87, and boosted cars are 91 or 93... so is that only true for newer cars? Does than mean 1990's and 1980's cars will benefit from higher octane?
My mechanic friend recommended chevron with techron fuel system cleaner with each oil change, but if additives are bad then how else can u burn off the carbon build up and etc? Or is that only helpful for older cars?
As for oil additives they say they are good for cars that use up a lot of oil.
03-01-2014, 05:09 PM
#6
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Join Date: Dec 2010
Location: CT
Posts: 1,472
An octane that is to high will cause issues, back in the late 90's I had a stock Camaro SS and I put in $40 bucks worth of 104 octane at the race track and within a day my check engine light came on and I ruined my oxygen sensors and had to replace them so, high octane could cause havoc on some parts. The car ran a little bit crisper with the high octane but, not worth the damage it caused me.
03-01-2014, 05:14 PM
#7
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I've been running 93 octane most of 100,000 miles and my engine still runs like new. I do have a 93 octane tune, but it's still the same engine with the same parts. No harm, no foul,
The newer engines will adjust the timing curve based on knock sensors, so if you put in higher octane the curve will advance up until the sensors detect knock and back off until it stops. By doing that, you will get a little more HP and TQ. My wife's Miata says the same thing, they recommend premium, but you can run regular but performance and mileage will be a bit lower.
The newer engines will adjust the timing curve based on knock sensors, so if you put in higher octane the curve will advance up until the sensors detect knock and back off until it stops. By doing that, you will get a little more HP and TQ. My wife's Miata says the same thing, they recommend premium, but you can run regular but performance and mileage will be a bit lower.
Last edited by Goldenpony; 03-01-2014 at 05:18 PM.
03-01-2014, 05:18 PM
#8
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Join Date: Jan 2014
Location: wi
Posts: 163
octane
the lower the octane number you can use without detonation the more power your gonna make. FI cars need a higher octane to prevent detonation from the higher cylinder temps&pressures. The car isnt going to know what fuel you put in it. So if it runs good on 87 with no knock you are going to make more power then on 91 with the same conditions. Lower the octane faster the flame front. So i have to disagree with your statement. Unless you have live time scanner and can watch for knock signal and see if you are getting knock and in extreme you will get a check engine lite. you not going to loss HP with a higher octane on a NA engine.
03-01-2014, 05:21 PM
#9
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Location: wi
Posts: 163
on the same note if you using N20 you may also need to run a higher octane fuel to prevent detonation. Just wanted to add that. But the additional Oxygen will more then make up for it. ;-) Gotta love the bottle!!!!!!!
03-01-2014, 05:58 PM
#10
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Join Date: Jun 2013
Location: Pennsylvania
Posts: 352
the lower the octane number you can use without detonation the more power your gonna make. FI cars need a higher octane to prevent detonation from the higher cylinder temps&pressures. The car isnt going to know what fuel you put in it. So if it runs good on 87 with no knock you are going to make more power then on 91 with the same conditions. Lower the octane faster the flame front. So i have to disagree with your statement. Unless you have live time scanner and can watch for knock signal and see if you are getting knock and in extreme you will get a check engine lite. you not going to loss HP with a higher octane on a NA engine.
