Kia Forte Forum banner

20 forte GT 93 octane

1 reading
34K views 142 replies 20 participants last post by  BlueStang  
#1 ·
When I run 93 octane fuel my check engine light comes on after a couple tanks, dealer tells me too much alcohol. In the manual it says 91 octane and below.

Is there a way to optimize it to run on higher octane fuel? I'm assuming a tuner like Racechip, but I wanted to see what yall think about it.
 
#79 ·
I don't want to challenge your times though I do like to open it up a bit. We have some saying use the various octanes and Kia says it is ok to run 87 octane. Call me crazy but if they thought their engines were gonna implode using 87, they would not have advised to use it.

It was a simple Q, what HP gains are obtained using the various octane rated gasoline? My point is that putting 89 rated octane gas.is not going to get you a lot more HP. I do put mid grade in mine btw.

I am not trying to beat people off the line and I don't have Civic SIs trying to race me though I do get a ton of compliments on the fire orange color and rebadging.

Sent from my Pixel 4a using Tapatalk
 
#80 ·
I don't want to challenge your times though I do like to open it up a bit. We have some saying use the various octanes and Kia says it is ok to run 87 octane. Call me crazy but if they thought their engines were gonna implode using 87, they would not have advised to use it.

It was a simple Q, what HP gains are obtained using the various octane rated gasoline? My point is that putting 89 rated octane gas.is not going to get you a lot more HP. I do put mid grade in mine btw.

I am not trying to beat people off the line and I don't have Civic SIs trying to race me though I do get a ton of compliments on the fire orange color and rebadging.

Sent from my Pixel 4a using Tapatalk
Lol I didnt mean to target you, or anyone, I've just been trying to prove that, based on my testing, I've not seen any differences in performance w/ this car (granted, up to 110 mph - the car is limited to 135-138 mph -Ive not reached that)...I use 89 just cuz lol I could just fuel up with 87 or 93 but Im happy w/ 89 - a happy medium :) I have not tested w/ 87, my guess would be about the same as 89 and 93...

Personally, I think its pretty cool that I get to say "I can do 6.31-6.4 sec to 60 sec in my car w/o 93 octane :p" lol considering that a Mazda 3 turbo does 5.9-6.1 sec with 93 octane ONLY (w/o launching).
 
#83 ·
Except he's not passive aggressive lol.

(I've been honored the last go-around with getting a PM stating "Piss off asshole and mind your own business.")
 
  • Like
Reactions: El Spicoli
#86 ·
The Forte GT is tuned for 87 Octane to produce the stated 201HP.

It is not like the EcoBoosts and others that needed the 91+ to produce the rated HP.
 
#88 ·
Yes, you are right. I'm aggressive when idiots like yourselves ask a for the lack of a better term "stupid question" and Master Mechanics like myself and Nova repeatedly explain knowledgeably without having to look it up online from a post written by another keyboard mechanic, then you want to get into a back and forth pissing contest. Would you argue with the doctor who answered your question because you read something different somewhere online? No, you wouldn't but you guys sure as hell want to do it here. I wish all of you the best with the mess that you have or will make of your cars. I fix and deal with enough ignorant customers all damn day long.
 
#90 ·
Alright alright, @NovaResource & @BlueStang I will have to try it for myself. I have driven 6,000 miles so far using 93. I have an ultra-gauge I can use to monitor timing advance to see if it beings retarding the timing more and more. I'm curious now.



Well you're just being aggressive-aggressive.
 
  • Like
Reactions: BlueStang
#91 ·
As a former '16 EB mustang owner, Ford RECOMMENDS 93 for improved performance - it's in the manual. You can run 87 youll just be slow....
93 vs 87 on THAT car makes a HUGE difference. HUGE. lol 93 yields 0-60s in the 5.4-5.6 sec, on 87 good luck getting sub 6 secs (for the '15-1'17 models before the 10 speed), the 10 speed on 87 might do 5.85 sec..on a good run.
Mazda with their 2.5t's do the same thing, though Mazda is more transparent about it unlike Ford. You can fuel up w/ 87 , youll just be slower...

The Forte is not one of those cars.
 
#92 · (Edited)
Kia Owners Manual:

83079


Use the fuel with the octane YOU want to. You're paying for it - not them. You don't need approval from moral superiors on the internet. BTW That is NORMAL OPERATION -- Kia is not about to add a statement for "performance operation" - that could turn out to be a warranty nightmare in a court of law...LOL!
 
#93 ·
“Or Higher” just mean you are required to have a minimum of 87. Below that causes damage but above that does not give more power. It just wastes money.
 
#94 ·
That's my point! It's their money and their car. If they want to burn 89 or 91 octane fuel, and feel better for it, more "power" to them.

I do not understand why people who don't own the car or buy the fuel feel they have a say in what the owner does!

If it was ALL ABOUT the money then why not berate them for buying a more expensive model when they could have saved even more money by buying an FE model?
 
#95 ·
All I set myself out to do was to find out if there was any differences in performance with higher octane. My testing proved there is NO improvements to be had with this specific car. I made a few comments that if you (owner) wishes to fuel up w/ 93 that's okay that I am not trying to steer you away from it. Like I posted in another comment, just know that it is no getting you better performance. That is all I wanted to contribute to this community. I don't understand why its such a heated debate...specially for the Forte, it is a great little car, and I actually like the fact that it can do mid-low 6 seconds w/ low octane whereas other cars NEED 93 to be FAST (EB mustang, Mazda, among others, of course, GTI/GLI's need 91, etc), but it is not set out to be a PERFORMANCE car.

By utilizing an OBDII, I've seen a peaks in boost of 17-18 psi with both octanes (that's impressive), avg of 16.5-17 psi.

If 93 makes anyone feel better, go ahead and fuel up w/ it. I am nobody to tell you what to do with your coin.
 
#99 ·
All I set myself out to do was to find out if there was any differences in performance with higher octane. My testing proved there is NO improvements to be had with this specific car. I made a few comments that if you (owner) wishes to fuel up w/ 93 that's okay that I am not trying to steer you away from it. Like I posted in another comment, just know that it is no getting you better performance. That is all I wanted to contribute to this community. I don't understand why its such a heated debate...
Because some people think they know everything and if you say anything that goes against their collective intelligence, they attack you for it. And then ban you. Actual intelligence used to be admired here. Back when this forum was active and vibrant and good.
 
#96 ·
What about air temps? Does the higher octane help with pre-detonation because the higher air temp, say like 90 or 100F (and higher lately lol)?
 
#98 ·
Yes, and when you're going up a steep hill, and when you give it gas at a low speed with the tranny in a high gear, and...

Kia says 87 octane or higher for normal operation. I'll bet dragstrip operation doesn't fit under "normal operation"...
 
#101 ·
Opinions are one thing facts are another.
Facts can be proven.
Opinions are based on feelings.

You can prove higher octane does not give better power on a stock Forte (such as was proven by currantredGT above).
You can’t prove an opinion or belief that higher octane does give more power.

“Facts don’t care about your opinion.”
-Ben Shapiro
 
#103 ·
Anytime you change the physical engine (raise compression, change cams, etc) or if you change the computer tune, then yes, you will see gains. The new tune makes the power and the higher octane allows those changes to work and prevents them from damaging the engine.

Not sure about RaceChip but quality ones will work. The problem is, there’s is a lot of junk out there too.
 
  • Like
Reactions: ZiggyM5
#104 ·
As far as I understand there is no tunning with the RaceChip as the JB4 for example. I did get mine to a dyno and it gained about 20+ hp and some 20+ lbs torque. The RaceChip comes with 7 pre-determined maps and I tested it in the higher set with no problems, knocking, or service light. One can feel the difference, though.

Thanks for your input.
 
#105 ·
I had a 2016 Ford Focus ST and it's power rating with 87 octane was 230 hp. With 93 it was 252 hp. There was no official rating for 91, I did 220 whp on 91 Road Race Engineerings Dynapak (EVO specialist).

87 is minimum octane. I made 201 whp with E20 on the stock tune. 91 octane with the stock wheels was 190 whp, with the Enkeis 195 whp.
 
#107 ·
I'm not convinced 93 does nothing. With the first tank of 87 I sensed a lot of surging under WOT and watched my ultra-gage as it showed timing go from +20 degrees advance to -2.5 multiple times. Y'all are free to keep doing what you're doing, but I most definitely noticed the difference and will personally be sticking with 93.
 
  • Like
Reactions: ForteGT2
#109 ·
Because everybody know the butt-dyno doesn't lie. Who need actual data or proof? The butt-dyno is always right.
 
#115 ·
Maybe if you can do three 15 second tests showing TIMING and RPM from idle to 70 MPH on the same road and nearly the same ambient temperature - one test each with 87, 89, and 93 (and the fuel tank would have to be ONLY ONE of the octanes or it will be flawed).

That way we could see the timing difference to get a real idea of any benefit.
 
#118 ·
This car heat soaks so easily. This is after sitting in a drive thru for ~7 minutes with no A/C at night in 85F ambient air temps. I wonder where the IAT sensor is located. 149F is hotter than any temp I ever saw from my Cruze or Cooper S.
Image
 
#120 · (Edited)
This car heat soaks so easily. This is after sitting in a drive thru for ~7 minutes with no A/C at night in 85F ambient air temps. I wonder where the IAT sensor is located. 149F is hotter than any temp I ever saw from my Cruze or Cooper S.
View attachment 83350
The IAT sensor is part of the MAP sensor right there on the intake. The heat soak is not from the intake - it is from the PCV system. 30% of idle intake air is coming from the PCV - where does the PCV air come from - INSIDE THE ENGINE, nice and HOT! That's why as soon as you give it throttle to get going the IATs come down quick - the percentage of cool air increases.

Here's how you can check it: Disconnect the PCV hose from the intake and plug it. Expect the engine to run rough and you may need to keep the throttle open to keep the engine running...but you won't see the "heat soak". Then reconnect the PCV hose. It is normal. A simpler way of checking it is to watch your IATs after starting the engine in the morning - it will take a LOT of idling before the "heat soak" starts because it will take some time for the engine to reach operating temperature. Once it reaches operating temperature you will see your "heat soak".

I don't know about the Cruize and CooperS but on the Cobalt 2.0 2.2 and 2.4 engines they did not use the traditional PCV system. Instead of a PCV valve they used a small metered hole (I think about .0625"/1/16") in the intake that lined up with a literal hole in the engine block. That "PCV" system was not 30% of idle air. There was NO WAY of installing a catch can on it AND the intake would collect a lot of engine oil - I drained my 2.2's intake of 1/2 cup of oil when I removed it! Occasionally in a panic stop my cobalt would shoot white smoke...no telling how much oil the engine ingested...LOL!
 
#123 ·
Resurrecting thread...because the forum is too quiet...:)

I found this while researching fuel additives:

2017 Kia Soul Long-Term Test (caranddriver.com)

Image

It's about the Soul with the 1.6T engine...and 40,000 miles of driving. No reason to believe the Forte GT 1.6T wouldn't behave the same.
 
#127 · (Edited)
Resurrecting thread...because the forum is too quiet...:)

I found this while researching fuel additives:

2017 Kia Soul Long-Term Test (caranddriver.com)

View attachment 84099
It's about the Soul with the 1.6T engine...and 40,000 miles of driving. No reason to believe the Forte GT 1.6T wouldn't behave the same.
That is why I like to do my own testings lol ;)

6.3s are extremely difficult to get, even when I was running 93 (I am still running the mid grade stuff)...


Ive not done anymore runs because weather has been crap even during night time (damn humid)...

Like I said in post #70, your biggest enemy is traction, temps, DA.

Ill be retesting, though, when temps improve to see if somehow I've gotten slower over times....

There was a guy here that made a post asking about 1/4 mile times as he did a 15ish @91 mph, or something like that...running 93.
SOOOOOO MANY factors that influence performance. Personally, Ive yet to see a trap speed of 91 mph on this car...lowest has been 93.5 mph with either 93 and 89.

This car is, on average, a 6.4-6.6 sec car...when the stars align and everything is great a 6.3 sec is possible. (DCT)
 
#126 ·
I stand by my logic. The turbo 1.6L has enough tech and creates enough boost to warrant using 93. But this car also is able to de-tune itself to allow the use of 87 without any harm done, it just saps a bit of the performance and fuel mileage in the process. This all depends on how you drive, if you aren't flooring it all the time, you will likely not notice this difference, but then again, why even get the GT if you're NOT going to floor it all the time.
 
#129 ·
I agree - if you want to pump in 87 Octane your car will do fine, it will detune when it needs to to keep pre-ignition from occurring.. If you want max power you will need to use higher octane gas.

Telling people they shouldn't use higher octane gas because it cost more is like telling people to just get a hamburger at a classy Steak House because the steak costs more...LOL!
 
#130 ·
I don't have any quantitative measurements, but, I can tell there is a slight difference enough for me to stick with 91 octane. The higher octane is also a preventative measure to reduce detonation. Also, with all the hills, stop and go, and high speed California freeways, my mpg is higher compared to 87 octane.
 
#131 ·
what was the point of resurrecting this thread again? lol

To those saying they feel a difference between octanes, I have been providing data showing there is none...lol I guess that don't matter...:) I have no idea about mpg's cuz I don't really track that.

In terms of longevity, well, you'd have to compare at certain intervals how one 1.6t is holding up at 25k, 50k, 80k miles, etc. premium 91+ vs non premium, no?. How about looking at the of the avg driver who doesn't install a catch can and one who does? (GDI issues that alone might kill performance if not maintained properly - using synthetic, changing oil frequently, quality of fuel regardless of octane?).
 
#132 ·
what was the point of resurrecting this thread again? lol

To those saying they feel a difference between octanes, I have been providing data showing there is none...lol I guess that don't matter...:) I have no idea about mpg's cuz I don't really track that.

In terms of longevity, well, you'd have to compare at certain intervals how one 1.6t is holding up at 25k, 50k, 80k miles, etc. premium 91+ vs non premium, no?. How about looking at the of the avg driver who doesn't install a catch can and one who does? (GDI issues that alone might kill performance if not maintained properly - using synthetic, changing oil frequently, quality of fuel regardless of octane?).
I won't say you're wrong and I won't tell someone who says they feel a difference that they are wrong. I accept everyone's opinion because that's what they think, feel, and believe based on THEIR experience. It does not have to be right or wrong.

I also don't believe in being so righteous that I can tell someone else what octane fuel they should use.
 
#133 ·
When you have fuel reformulated to burn cleaner while reducing mpg and power, higher octane can make a difference. California, Arizona, and Nevada has horrible gasoline. I'm not surprised that you really didn't find much difference and since you have 93, you are probably in the midwest or east coast where the fuel is better at making power than Cali gas. i bet your mid grade is just as good as our 91.
 
#136 ·
The only difference between 87 octane and 93 on this car is that those buying 93 are spending too much money for nothing in return. There is no added performance, no added MPG, and the old wives tale that it keeps you engine cleaner is not true at all with modern gasoline. Some people are stuck in their ways and insist its better. This cars computer does nothing with it. So..... yeah.
 
#137 ·
Please tell "Car and Driver" they don't know what they're talking about:


"Test Results
Our initial test of the Soul found about a half-second difference in the zero-to-60-mph time between using regular and premium-grade fuel (the 6.3-second figure in our specs is the result on 93 octane). At the end of our test, the car performed similarly to when new, with most measures improving by 0.1 second, which surprised us only in that we'd noticed a steadily worsening slippage in the dual-clutch automatic transmission that made for subjectively less satisfying launches, with an early 1-2 upshift. Perhaps the performance would have improved more had the gearbox stayed as sharp as it was when new. At higher revs in higher gears, the transmission was less of a concern, and getting the Soul to 120 mph took 1.4 seconds less than it had at first."