What grade do you guys/gals use in your z24's with 2.4's? and why
87 there is no reason to use anything else. unless you are boosted and need better control of when the gas detonates there is no reason to switch.
my firebird ran just fine on it as well.
Mike Demo wrote:87 there is no reason to use anything else. unless you are boosted and need better control of when the gas detonates there is no reason to switch.
my firebird ran just fine on it as well.
This.
Putting higher grade gas in your car does nothing but cost you more money, unless, like Mike said, you are running boost. Still, its funny to listen to the ricers talk about how their civics "only take premium" because, in their minds, they get better mileage.
well i use 89. i have put a tank of all 3 grades in and i found 91 and 89 give me about the same mileage so why pay more for the same mileage as 89. that is the best way of determining which grade your engine should use,
Cavaclysmic04 wrote:Mike Demo wrote:87 there is no reason to use anything else. unless you are boosted and need better control of when the gas detonates there is no reason to switch.
my firebird ran just fine on it as well.
This.
Putting higher grade gas in your car does nothing but cost you more money, unless, like Mike said, you are running boost. Still, its funny to listen to the ricers talk about how their civics "only take premium" because, in their minds, they get better mileage.
Not to get off topic but
a buddy of mine has a 96 civic hatch with a H22A the lowest he can use is 93 unless he can find higher his comp is 11.5 to 1
LarryMartin830(Soon With Z) wrote:Cavaclysmic04 wrote:Mike Demo wrote:87 there is no reason to use anything else. unless you are boosted and need better control of when the gas detonates there is no reason to switch.
my firebird ran just fine on it as well.
This.
Putting higher grade gas in your car does nothing but cost you more money, unless, like Mike said, you are running boost. Still, its funny to listen to the ricers talk about how their civics "only take premium" because, in their minds, they get better mileage.
Not to get off topic but
a buddy of mine has a 96 civic hatch with a H22A the lowest he can use is 93 unless he can find higher his comp is 11.5 to 1
well he has a high compression ratio thats why he needs a higher grade fuel. the highest compression ratio gas will run is about 13.5:1
Would like to add some technical info here.
Octane is a fuel's rating of resistance to knock, not the quality of the fuel or the cleanliness of the fuel. Almost every engine designed today is made to run on 87. Higher compression motors with turbo's or superchargers (And many imported 6 cylinders) require a higher octane because of the higher compression ratio. Think of a diesel engine. The octane of diesel fuel is 40. Why? Because diesel fuel is meant to self detonate. Gasoline is not.
Hope this helps.
^^^ Diesel is rated in Cetane, not the same as octane. Comparing apples to oranges.
^^^ He's right about the octane rating of diesel though.
i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
octane ratings is mainly for knock. its not gonna give any car better gas milage.
octane is not its resistance to knock, its resistance to detonation.
Deez Nutz wrote:^^^ Diesel is rated in Cetane, not the same as octane. Comparing apples to oranges.
My mistake, but my point of diesel being self-igniting is valid.
BuiltNBoosted wrote:octane is not its resistance to knock, its resistance to detonation.
I usually say it's resistance to detonation. Not sure why I used the word knock instead. Must have been thinking of something else.
Sunfiretun3r wrote:Deez Nutz wrote:^^^ Diesel is rated in Cetane, not the same as octane. Comparing apples to oranges.
My mistake, but my point of diesel being self-igniting is valid.
Diesel is ignited by the heat of compression(compression ignited). If it was self-ignited then it would burn up as soon as it was made and would be impossible to use.
its an old concept. time for something new to take the reigns. - Z yaaaa
Tinkles wrote:Sunfiretun3r wrote:Deez Nutz wrote:^^^ Diesel is rated in Cetane, not the same as octane. Comparing apples to oranges.
My mistake, but my point of diesel being self-igniting is valid.
Diesel is ignited by the heat of compression(compression ignited). If it was self-ignited then it would burn up as soon as it was made and would be impossible to use.
That's what I meant. There's n ot spark plug, and theres only a glow plug for when the engine is cold. And the Cummins has a heated intake manifold rather than glow plugs. I know.
You know, I'm just gonna stop. Forget I posted anything.
I put 90 in mine because that's the lowest the gas station I go to sells. Its the same price as 87 at other stations, so why not?
2010 Honda Fit LX
u kiddin wrote:well i use 89. i have put a tank of all 3 grades in and i found 91 and 89 give me about the same mileage so why pay more for the same mileage as 89. that is the best way of determining which grade your engine should use,
I tested a couple of tanks of gas with each grade, I found that 89 got me the best milage in my old Z24 and now with the Envoy I currently have, Now my wifes G3 is just fine with the low grade.
NfamousGMT360 wrote:u kiddin wrote:well i use 89. i have put a tank of all 3 grades in and i found 91 and 89 give me about the same mileage so why pay more for the same mileage as 89. that is the best way of determining which grade your engine should use,
I tested a couple of tanks of gas with each grade, I found that 89 got me the best milage in my old Z24 and now with the Envoy I currently have, Now my wifes G3 is just fine with the low grade.
thats what always makes me crack up... yeah you say you get better mileage with 89, but your also paying more. So unless your getting 5+ better mpg, your wasting your money
Wifes car gets 87 costs 10 cents more but gets way better gas milege than 89, cavalier gets 91 or 93 depending where im at town I live in only has one station with premium and its only 91
my 2.4l ecotec COBALT, the manual says 91 oct or better...figure if im getting 91...mite as well fawk it and get the good stuff and go 93...
but thats just me i guess. worth it, prolly not. any purpose no. just makes me feel good i guess. stock 2.4 cobalt runs at 10.4:1
Cavaclysmic04 wrote:Mike Demo wrote:87 there is no reason to use anything else. unless you are boosted and need better control of when the gas detonates there is no reason to switch.
my firebird ran just fine on it as well.
This.
Putting higher grade gas in your car does nothing but cost you more money, unless, like Mike said, you are running boost. Still, its funny to listen to the ricers talk about how their civics "only take premium" because, in their minds, they get better mileage.
Funny how all of my vehicles are now using premium.
Since doing so, I've tuned two of the cars to give more spark to make full use of the higher premium grade, and the results have been more power with much better gas mileage.
Funny how people think that because our cars take 87 from the factory that the 93 won't do any good.
Those with HPTuners know better and how the fuel maps are designed to go into the high octane mode as long as no knock is heard by the knock sensor.
So even though you're using the 87 gas in your cars, the ECU will try to use the spark maps in the high octane side until knock is heard.
So why not just use 93 octane in the first place and take full potential of the high octane spark maps that provide more power and overall better performance in which knock will probably never occur because of your higher grade gas.
Did the same with my non Cavalier daily driver by using 93 octane.
I increased the timing by a few degrees to take advantage of the higher octane rating and came away with more power and way better gas mileage.
Going from 34-36 mpg with the 87 gas to 42mpg with timing increase and 93 octane makes for a pretty good reason to switch.
Just sayin......
Misnblu.com
Newbie member since 1999
Thank you Dave and JBO! 
so what youre saying is once youve bought a $500 program you can get the benefit of running gas that will save you $200 I would have thought it would be clear that this was a stock for stock debate. not well i tuned my mapping...
Well i put mid grade in and my car runs better for some reason... like when i put 87 it seamed alittle sluggish but i put in 89 the sluggishness went away. tomorrow when i put gas in i will try 93 just to see but im not going back to 87
