Which fuel for the 2.4
NEWS

  1. Welcome to Kia Optima Forum General discussion forum for Kia Optima

    Welcome to Kia Optima Forum - a website dedicated to all things Kia Optima.

    You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, Join Kia Optima Forum today!
+ Reply to Thread
Page 1 of 3 123 LastLast
Results 1 to 10 of 28

Thread: Which fuel for the 2.4

  1. #1
    Learner's Permit
    Join Date
    Jun 2014
    Location
    Australia
    Posts
    191
    Year
    2012
    Make
    Kia
    Model
    Optima
    Trim
    Platinum

    Which fuel for the 2.4

    Hello all,

    I know this has been done to death but I can't find anything relating specifically to the 2.4L. I've been running unleaded 87 (91 octane) in the car but found the car very sluggish especially going up a hill. If I switch to 91 (95 octane) fuel the car seems to have a lot more power especially in the mid range. But I have noticed the engine runs rougher and harsher. In Australia 95 octane is the better quality fuel but I don't know if i'd be wasting money using it. The manual just says 91 Octane or higher. Both fuels are just normal unleaded without ethanol.

    I know the 2.0T gains horsepower but not sure what to use in the 2.4?

  2. Remove Advertisements
    Optima Forums
    Advertisements

  3. #2
    Driver's License
    Join Date
    Oct 2013
    Location
    Fort Worth, Texas
    Posts
    328
    Year
    2013
    Model
    Optima SWP
    Trim
    EX
    Use whatever you like as long as it meets the minimum. Using a higher octane doesn't give you that much more power to notice in daily driving. You'll maybe gain 2 or 3 hp on the very top end of the rpms. You won't notice that.

    And is that some weird thing in Australia that the 87 fuel is really 91 octane? That makes no sense lol.
    Premium & Technology Packages
    LED Taillights
    LED Bumper Lights
    K&N Drop-in filter
    Mud guards
    50 W CREE LED Reverse Lights
    K5 Trunk Emblem

  4. #3
    OptimaForums Veteran KingFatty's Avatar
    Join Date
    May 2013
    Posts
    1,207
    Year
    2012
    Model
    Black SX Prem. & Tech.
    Might be the placebo effect. Ask a friend to fill your car next time, and randomly choose which gas is used without telling you. Then drive the car and see if you can tell the difference.

  5. Remove Advertisements
    Optima Forums
    Advertisements

  6. #4
    Learner's Permit
    Join Date
    Jul 2015
    Location
    Eastern Nc
    Posts
    135
    Year
    2015
    Make
    Kia
    Model
    Optima
    Trim
    Ex
    I run premium in my 2.4 and notice my car has a little more pep and I feel likes it helps the car run better. im also running a short ram intake also.

  7. #5
    OptimaForums Veteran carguy75's Avatar
    Join Date
    Feb 2015
    Location
    Lawrenceville,GA.
    Posts
    1,539
    Year
    2014
    Make
    KIA
    Model
    Optima
    Trim
    SXL
    You can use any fuel from 87(91 outside US) to 93(98) octane.

    The car may run better with 91(95 outside US) octane because the engine has a 11:1 compression ratio(very high for a street engine), which usually means high octane gas use only.

    However, the direct injection technology allows the use of regular gas without engine damage just like in the turbo engines.

    The engine may pick up a few extra horsepower across the whole rpm range while using premium since the ecu do not have to pull power to account for engine knock when using 87(91 outside US) octane gas.
    Last edited by carguy75; 10-23-2015 at 02:49 PM.
    2014 Black KIA Optima SXL loaded w/

    AEM dry performance drop-in air filter w/radiator cowl panel removed
    Hella yellow HID look H7 high beam light bulbs
    Running only Shell V-power 93 octane gas
    5w-40 Total Quartz 9000 Energy synthetic oil
    NGK ILKR8E6 spark plugs(1422)
    Bosch Icon wiper blades- 24A, 18A
    Black check-mark fog light trim
    Michelin Primacy MXM4 225/45-18 tires
    Hawk HPS 5.0 Front brake pads HB661B.667
    Centric Posi Quiet Ceramic Rear brake pads 105.15440

  8. #6
    Learner's Permit
    Join Date
    Feb 2014
    Location
    Vernon Hills, IL
    Posts
    103
    Model
    '14 SXL
    Octane is calculated differently in the US vs. Australia/Europe. Australia uses RON but the US uses AKI (an average of RON and MON).
    So 87 (AKI) in the US = 91 (RON) in Australia.
    2014 Kia Optima SXL (sold)
    - added hardwired V1, J5 FSTB, AEM Dryflow cone filter w/ custom bracket and 35% tint
    2015 Mini Cooper S Hardtop
    - added hardwired V1 and 35% tint
    2014 Pathfinder Platinum Premium 4WD
    - added hardwired V1, roof rails, running boards, K&N drop-in filter and 35% tint
    2007 Mini Cooper S Convertible
    - added hardwired V1, K&N drop-in filter and Kenwood Excelon KDC-X599 receiver

  9. The Following User Says Kudos to chipfiev For This Useful Post:


  10. #7
    OptimaForums Veteran carguy75's Avatar
    Join Date
    Feb 2015
    Location
    Lawrenceville,GA.
    Posts
    1,539
    Year
    2014
    Make
    KIA
    Model
    Optima
    Trim
    SXL
    Quote Originally Posted by chipfiev View Post
    Octane is calculated differently in the US vs. Australia/Europe. Australia uses RON but the US uses AKI (an average of RON and MON).
    So 87 (AKI) in the US = 91 (RON) in Australia.
    Thanks I changed my post to minimize confusion for the OP about octane.
    2014 Black KIA Optima SXL loaded w/

    AEM dry performance drop-in air filter w/radiator cowl panel removed
    Hella yellow HID look H7 high beam light bulbs
    Running only Shell V-power 93 octane gas
    5w-40 Total Quartz 9000 Energy synthetic oil
    NGK ILKR8E6 spark plugs(1422)
    Bosch Icon wiper blades- 24A, 18A
    Black check-mark fog light trim
    Michelin Primacy MXM4 225/45-18 tires
    Hawk HPS 5.0 Front brake pads HB661B.667
    Centric Posi Quiet Ceramic Rear brake pads 105.15440

  11. #8
    Learner's Permit
    Join Date
    Jun 2014
    Location
    Australia
    Posts
    191
    Year
    2012
    Make
    Kia
    Model
    Optima
    Trim
    Platinum
    Quote Originally Posted by neemster View Post
    Use whatever you like as long as it meets the minimum. Using a higher octane doesn't give you that much more power to notice in daily driving. You'll maybe gain 2 or 3 hp on the very top end of the rpms. You won't notice that.

    And is that some weird thing in Australia that the 87 fuel is really 91 octane? That makes no sense lol.
    I just notice the car more responsive in the mid range. But i'm not sure if it's detonating early or pinging but the engine does sound harsher. I don't know if the 2.4L will adjust for the higher octane?.

    Quote Originally Posted by RichardTheKiaTech View Post
    I run premium in my 2.4 and notice my car has a little more pep and I feel likes it helps the car run better. im also running a short ram intake also.
    Have you noticed any pinging or knocking?

    Quote Originally Posted by carguy75 View Post
    You can use any fuel from 87(91 outside US) to 93(98) octane.

    The car may run better with 91(95 outside US) octane because the engine has a 11:1 compression ratio(very high for a street engine), which usually means high octane gas use only.

    However, the direct injection technology allows the use of regular gas without engine damage just like in the turbo engines.

    The engine may pick up a few extra horsepower across the whole rpm range while using premium since the ecu do not have to pull power to account for engine knock when using 87(91 outside US) octane gas.
    Does that compression ratio apply also for the 2.4L engine ?
    So you're saying our ECU will adjust for the higher octane ?

    One of the reasons I was also curious about running the higher octane is that the quality of the fuel here is better. It contains a lot less sulphur.

  12. #9
    OptimaForums Veteran carguy75's Avatar
    Join Date
    Feb 2015
    Location
    Lawrenceville,GA.
    Posts
    1,539
    Year
    2014
    Make
    KIA
    Model
    Optima
    Trim
    SXL
    Quote Originally Posted by sshazam View Post
    I just notice the car more responsive in the mid range. But i'm not sure if it's detonating early or pinging but the engine does sound harsher. I don't know if the 2.4L will adjust for the higher octane?.



    Have you noticed any pinging or knocking?



    Does that compression ratio apply also for the 2.4L engine ?
    So you're saying our ECU will adjust for the higher octane ?

    One of the reasons I was also curious about running the higher octane is that the quality of the fuel here is better. It contains a lot less sulphur.
    Yes.

    The 2.4 engine has the 11:1 compression.

    The turbo engine has 9:5 compression.

    Direct injection allows both engines to use regular gas with lower octane than both engines would be able to use without direct injection due to high compression and turbo charging.

    The ecu cuts power to protect the engine in both cars when using regular gas.

    Premium gas allows both engines to run at their best.
    2014 Black KIA Optima SXL loaded w/

    AEM dry performance drop-in air filter w/radiator cowl panel removed
    Hella yellow HID look H7 high beam light bulbs
    Running only Shell V-power 93 octane gas
    5w-40 Total Quartz 9000 Energy synthetic oil
    NGK ILKR8E6 spark plugs(1422)
    Bosch Icon wiper blades- 24A, 18A
    Black check-mark fog light trim
    Michelin Primacy MXM4 225/45-18 tires
    Hawk HPS 5.0 Front brake pads HB661B.667
    Centric Posi Quiet Ceramic Rear brake pads 105.15440

  13. #10
    OptimaForums Veteran Crazy-N8's Avatar
    Join Date
    Sep 2012
    Location
    Oakland/ Council Bluffs IOWA
    Posts
    1,357
    Model
    2013 Optima SX
    Trim
    Prem & Tech Pkg
    These motors are not like the hyndai engines that gain a few HP from running higher octane gasoline...so please stop saying that they do.
    2013 Kia Optima SX-T Remington Red.
    Premium and Tech package.
    K5 Optima Store EXLED inteior 5k kit/license plate
    Megan racing 2.5" Quad tip exhaust
    Injen Intake Polished
    HKS SSQv BOV
    coming soon===> Saiku Michi OCC's

    Boricua power! +0HP!

    Sponsored in part by K5OPTIMASTORE.COM

    Traded in: 2013 Kia Optima LX Satin Metal

  14. Remove Advertisements
    Optima Forums
    Advertisements

+ Reply to Thread
Page 1 of 3 123 LastLast

Similar Threads

  1. Fuel mileage
    By riVerRaT in forum Optima General Discussion
    Replies: 18
    Last Post: 10-14-2014, 11:22 AM
  2. First fuel up
    By MikedUp15 in forum Optima General Discussion
    Replies: 3
    Last Post: 11-16-2013, 07:05 PM
  3. Fuel Gauge
    By 2013-optima in forum Entertainment: Audio, Navigation, and Electronics
    Replies: 2
    Last Post: 05-14-2013, 11:17 PM
  4. Grade of Fuel
    By Exhaloprez in forum Optima General Discussion
    Replies: 12
    Last Post: 02-28-2012, 11:10 PM
  5. What fuel do you use in your SX?
    By Bluemarlin87 in forum Optima Engine and Technical Discussion
    Replies: 9
    Last Post: 11-21-2011, 06:32 AM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
Powered by vBadvanced CMPS v4.1.2