Trigger
09-15-2009, 06:26 AM
Hello all, I have been lurking for a little while but this is my first post. We just bought a 09 Civic Si, originally mpg was not my first concern. To my wifes annoyance I am starting to hypermile it ("Honey ease up your hosing my mileage" "C'mon Shift, Shift"). my logbook as follows:
299.8 10.2 = 29.4
317.5 10.8 = 29.4
331.8 10.5 = 31.6 -- aired tires up to 39psi (from dealer 32)
370.6 10.9 = 34 -- up to 45psi (max sidewall is 50)
I figure its not too bad beating the 29 highway rating this does include several runs up to high rpm so im sure i can improve quite a bit.
It would seem that the air pressure is of course making a difference some of that may be due to tires and engine breaking in as well. My question is; I understand the FE benefits decrease as the the pressure increases (ie from 32-37psi will have a larger impact than 45-50), is there a point when the higher pressure actually is a detriment to handling (especially in a lightly loaded car)? There is a couple of parts on my commute where I coast down a couple of large hills where the road is twisty I dont like to hit the brakes too much :) (at all). I think I will try 50psi anyway just wondered if anyone had any data or experience with this.
I also have a 05 HAH that has been a great car for us, I guess we have averaged 36-37 with this combined. I want a scan gauge too :)
299.8 10.2 = 29.4
317.5 10.8 = 29.4
331.8 10.5 = 31.6 -- aired tires up to 39psi (from dealer 32)
370.6 10.9 = 34 -- up to 45psi (max sidewall is 50)
I figure its not too bad beating the 29 highway rating this does include several runs up to high rpm so im sure i can improve quite a bit.
It would seem that the air pressure is of course making a difference some of that may be due to tires and engine breaking in as well. My question is; I understand the FE benefits decrease as the the pressure increases (ie from 32-37psi will have a larger impact than 45-50), is there a point when the higher pressure actually is a detriment to handling (especially in a lightly loaded car)? There is a couple of parts on my commute where I coast down a couple of large hills where the road is twisty I dont like to hit the brakes too much :) (at all). I think I will try 50psi anyway just wondered if anyone had any data or experience with this.
I also have a 05 HAH that has been a great car for us, I guess we have averaged 36-37 with this combined. I want a scan gauge too :)