• Welcome to CivicXI.com everyone!

    If you're joining us from CivicX.com, then you may already have an account here!

    As long as you were registered on CivicX.com as of May 24, 2020 or earlier, then you can simply login here with the same username and password!

10th.gen hatch to 11th. Si fuel economy

absolude

Senior Member
Joined
Dec 18, 2017
Threads
3
Messages
165
Reaction score
19
Location
GTA
Vehicle(s)
KW SC 2007 CSX Type S, 2023 PWP Si
Due to the AC disappointment of the 10th gen., I decided to switch cars so I'm now the very happy owner of a white 2023 Si.
The car is a huge improvement over my 2018 LX Hatch even though it had Si springs installed.
Only negative I can see is the worse fuel economy. This is surprising since I'm taking it easy at the moment.
FE is worse than previous car on either custom tune or stock, also compared to old car when 5W-30 oil was used.
The Si is about 160lb. heavier here in Canada. Would that make the difference?
Anyone moving from one generation civic to the next had similar experience?
Sponsored

 

Shankmeyster

Senior Member
Joined
Mar 15, 2017
Threads
33
Messages
1,964
Reaction score
367
Location
AZ
Vehicle(s)
23 Si
I'm getting better average MPG's on my 23 Si than either of my 10th gen hatches. I don't know why you'd use 5w-30 if you aren't tracking the car. I've run multiple of these through Arizona summers on 0w-20 and no issues. That viscosity is gonna reduce your mpg's significantly.
 

Shankmeyster

Senior Member
Joined
Mar 15, 2017
Threads
33
Messages
1,964
Reaction score
367
Location
AZ
Vehicle(s)
23 Si
Oh, they can also deny engine warranty if they find that you were using a different viscosity with an engine failure btw. It's real easy to send oil out for analysis.
 
OP
OP

absolude

Senior Member
Joined
Dec 18, 2017
Threads
3
Messages
165
Reaction score
19
Location
GTA
Vehicle(s)
KW SC 2007 CSX Type S, 2023 PWP Si
Thanks for the responses.
I'm using the same 91 Octane Shell gas as before. Taking it easy since I'm still breaking it in.
I experimented a couple of times with the 5W-30 because I didn't like the rougher sound on 0w-20. Fuel economy was surprisingly close but I used an oil that had low viscosity for a 30 weight oil.

I heard in the past of cars having better FE after break-in. Maybe is time for me to experience that.
 


OP
OP

absolude

Senior Member
Joined
Dec 18, 2017
Threads
3
Messages
165
Reaction score
19
Location
GTA
Vehicle(s)
KW SC 2007 CSX Type S, 2023 PWP Si
Oh, they can also deny engine warranty if they find that you were using a different viscosity with an engine failure btw. It's real easy to send oil out for analysis.
This oil recommendations are really strange. In Europe dealers would commonly use 5W-30 in these engines, especially for the manual ones.
 

chopsuey34

Senior Member
Joined
Jul 20, 2022
Threads
3
Messages
117
Reaction score
80
Location
Michigan
Vehicle(s)
Civic Si
Thanks for the responses.
I'm using the same 91 Octane Shell gas as before. Taking it easy since I'm still breaking it in.
I experimented a couple of times with the 5W-30 because I didn't like the rougher sound on 0w-20. Fuel economy was surprisingly close but I used an oil that had low viscosity for a 30 weight oil.

I heard in the past of cars having better FE after break-in. Maybe is time for me to experience that.

You should use what Honda recommends, which is 0W20.

1.5T average fuel economy is known to rise even with 2000 miles on the odometer as the engine fully breaks in. If you are still in the break in phase, you should expect lower fuel economy. Report back at 4000 miles or so.
 

VarmintCong

Senior Member
First Name
Chris
Joined
Sep 23, 2016
Threads
4
Messages
1,492
Reaction score
480
Location
Taiwan
Vehicle(s)
2023 Ford Focus ST-Line
Due to the AC disappointment of the 10th gen., I decided to switch cars so I'm now the very happy owner of a white 2023 Si.
The car is a huge improvement over my 2018 LX Hatch even though it had Si springs installed.
Only negative I can see is the worse fuel economy. This is surprising since I'm taking it easy at the moment.
FE is worse than previous car on either custom tune or stock, also compared to old car when 5W-30 oil was used.
The Si is about 160lb. heavier here in Canada. Would that make the difference?
Anyone moving from one generation civic to the next had similar experience?
My 2020 Si didn't get as good mileage as my 2017 Sport hatch, was your hatch manual? That might make a small difference as well.
 
OP
OP

absolude

Senior Member
Joined
Dec 18, 2017
Threads
3
Messages
165
Reaction score
19
Location
GTA
Vehicle(s)
KW SC 2007 CSX Type S, 2023 PWP Si
My 2020 Si didn't get as good mileage as my 2017 Sport hatch, was your hatch manual? That might make a small difference as well.
Yes, my hatch was manual. No power mods except the custom tune done by Derek.
I was getting better fuel economy on the tune than with the stock calibration.
 


OP
OP

absolude

Senior Member
Joined
Dec 18, 2017
Threads
3
Messages
165
Reaction score
19
Location
GTA
Vehicle(s)
KW SC 2007 CSX Type S, 2023 PWP Si
Just to clarify, the 5W-30 oil was used in the hatch only.
The Si only has about 400 miles on the clock.

A lot of people are using heavier engine oils with absolutely no ill effect.
5W-30 is among the oils recommended by Honda for the 1.5l turbo engine in Europe.
The 0W-20 recommendation in north America has more to do with the EPA fuel economy standards than longevity engine longevity.
With the fuel dilution the 0w-20 is getting dangerously thin in some cars, as found in oil analysys. Other than that is a great oil, since is 100% esters, IIRC.
https://www.civicx.com/forum/threads/oil-analysis-database.21607/
 
OP
OP

absolude

Senior Member
Joined
Dec 18, 2017
Threads
3
Messages
165
Reaction score
19
Location
GTA
Vehicle(s)
KW SC 2007 CSX Type S, 2023 PWP Si
no, mostly 40 mile an hour cruising back and forth to work
I could only dream .... Toronto turning so called Green City is a traffic nightmare.
 

MorrisGray

Senior Member
First Name
Tony
Joined
Feb 27, 2020
Threads
1
Messages
141
Reaction score
31
Location
Rock Spring, GA
Vehicle(s)
2006 Mazda3 5sp manual, 2012 Genesis sedan
I would guess it is the gearing in the SI being for better 0-60mph time. More sporty and also tuned for more hp than the other Civic models and trims. You would need to compare 2023 SI mpg to a 2022/2021/2020/2019/2018 year model.
Sponsored

 
 




Top