[_sambo]

i average 18-20 mpg city and 27-28 highway on 93 octane. generally around 315 miles to the tank sometimes more if i shift under 3000 RPM. when my gas light comes on i can get a good 30 miles out of it but dont like to force the fuel pump to work hard.

 

[Ek9B18]

If 101 did zip, then 93 would do zip.

1 - It takes time to actually do anything.

2 - You only really notice it if you're driving balls out.

I used to run a 50/50 100/93 mix on my JDM swapped civic. On a 2 day track event, I wouldn't really notice it till the second day and the change was subtle. There was an increase in the final speed at the end of the main straight. My guess was maybe 10 hp tops. I can't feel 10 HP in the butt-dyno. Maybe other people are more sensitive.

The JDM engine had higher compression and was tuned to use higher octane so, it's very possible the our USDM engines simply can't use it. On something like a WRX or STI it's pretty noticeable if you look at the knock-map. Boosted cars are always octane limited.

if i shift under 3000 RPM. when my gas light comes on i can get a good 30 miles out of it but dont like to force the fuel pump to work hard.

I don't let it get below 1/4 tank. I see no reason to push it to the edge. It doesn't improve performance in any way.

 

[chrisridebike8]

So how do our cars run on 93-94octane? I tried 101 racing fuel once. I just could not resist, even though it was $10 a gal. We only have 91 in SoCal. The 101 did absolutely zip, but, hey, I would have regretted not trying it.

As stated above, it takes time for the car to adapt. More importantly, you have to be tuned for that fuel in order to take advantage of it. The stock ECU will not advance timing enough to make a difference. Some cars may even make LESS power on race gas. Additionally, some fuels have a different stoichiometric coefficient. For example, most pump gas is around 14.7-14.2. But race gas like MS109 is around 13.5 so the fuel air ratio the car is trying to achieve on a stock tune is not optimal for that fuel. The car needs to run what it thinks is richer on MS109 in order to make its max power. And on this engine left in NA form, I doubt you would feel anything. My C63 with a race gas tune and MS109 made like 10 whp more than 93 octane. Save your money. Race gas makes a bigger difference with very high compression or boost.

 

[FrankieCarbone]

Its old,heavy,slow, and bad on gas period.

dannyboy89, damn bro, sounds like they put a gun to your head to own a IS.

Anyways i live in NYC and commute kinda far to work (from the bronx to queens) and its pretty much half highway half city. When i drive like a complete SISSY i get 300 a tank, and when i drive it like a normal car, i get about 220 miles per tank (110-120 miles when i hit the middle notch)

Yeh the gas mileage sucks on these cars, and it dosent help that it requires the most expensive gas, but i love the fact that im driving a REAL car. You can keep newer fancy looking plastic toys, i love the fact that my car is rear wheel driven 2jz powered machine.

 

[Savage_IS300]

Glad to see most members are getting the same numbers I do, typically ~23-25 highway and 18 or so city. When I visit my parents I can get there and back on a tank which includes a bit of driving in town. Like clockwork the fuel light will come on right as I'm getting home at 390-410 miles on the trip.

I did get ~28-29 mpg on a long trip once, drove the car like a grandpa and tried some hypermile techniques, didn't go over 75mph. <--- nothing about that trip was worth the $10 I saved on gas.

 

[jz416]

The way I look at it, it is not the car to buy if you aren't willing to spend the extra 1 - 2 hundred bucks a month on gas to not drive a FWD piece of crap.

 

[FrankieCarbone]

Glad to see most members are getting the same numbers I do, typically ~23-25 highway and 18 or so city. When I visit my parents I can get there and back on a tank which includes a bit of driving in town. Like clockwork the fuel light will come on right as I'm getting home at 390-410 miles on the trip.

I did get ~28-29 mpg on a long trip once, drove the car like a grandpa and tried some hypermile techniques, didn't go over 75mph. <--- nothing about that trip was worth the $10 I saved on gas.

390 on a trip? wow. i havent taking a road trip yet, but i hope i get those numbers when i drive down to florida from new york in march.

 

[The Nuke]

The only way you get 38 mpg on these cars is if you're using that "gauge" to determine your mpg hahaha. :fool: If that's the case, I often get 80mpg city driving...

That said... I just compared the exact amount of gas I put in (4.5 gal) compared to miles (~ 90) to get 20.5 mpg.

 

[iSNin0]

Terrible

 

[hoffmania2392]

I'm currently throwing a code for both cats being clogged and plan on replacing them with headers. I also replaced some very overdue sparkplugs. I'm curious to see if they help mileage as much as I think they will.

 

[isthreehun]

I've had plenty of these cars, and my friend has had a couple too, they get 19-20mpg, for sure, tune up and all, driving normally (for me that's a good amount of highway driving at about 75-80) and it gets 19 or 20. Also, I don't put premium in it, regular for me. I always figured it didn't have enough power to hurt itself. And it didn't after 30k miles anyways (and when I bought it had 165k on it already).

So... not great at all. It's a nice car but they do burn a lot of fuel. I found that most bigger cars do though, for the most part it seems like they get just over 20 usually. That's why I daily a civic still haha.