[Charles]

I have consistently gotten 30-32 mpg with my ZC (in an 89 Si with hybrid tranny). I keep hearing people say they get 40 mpg in their Si rexes. I just don't believe it. I came across my original window sticker and it says the mpg estimates (which are often imflated) are 28 city and 33 highway. Then with the more powerful ZC I don't see how 40 mpg is possible. I can only figure it is due to aftermarket wheels and tires throwing off the odometer.

What do you think?

 

[ComposiMo]

I can only figure it is due to aftermarket wheels and tires throwing off the odometer.

:rockon:

My thoughts exactly... it doesn't take much to throw this reading off that far over he course of a tankfull of driving.

 

[Charles]

And also Ethanol is added which reduces mpg.

 

[zerocool1014a]

yeah thats a bit hard to believe.. i think the best you could probably get would be around 35 and you would have to be driving it really really well.. although i drive an hf and have gotten at best 48mpg

 

[jfrolang]

In 5 years of keeping track of mileage, I've never hit 40mpg either. My best was 39mpg on the stock 13" steelies. I can count the number of times a full tank resulted in better than 36mpg on one hand.

 

[Charlie]

i've hit like 40.something once. high 30s often, if its mostly highway.

but also 19 mpgs once....

thats in my 90 Si, stock wheels 195-65-14 tires i think.

 

[crxter]

I have a 90 HF with Si interior. I swapped a D16y7 which is basically the same as an A6 ( engine had 312 miles) . Before I put the turbo in, I got 300 to 310 miles on a 7 to 7.2 gallon fillup. That averages roughly 40MPG.
Super consistently it did that for 2 years, then I went FI and it dropped to 250 miles per 7 gallons.
No AC and I didn't drive it hard.

 

[jmart]

In my stock 91 Si with nothing more than 15" teg ls rims and 195/50 yokahamas i would average 36 mpg with something like a 70/30 highway to streets split i think. i did record a few instances of 39mpg on cross country trips. nowadays i'm doing mostly streets and i get 32-34 dpeending, but i usually flog it.

 

[mattminerDOTcom]

on my way to N12 and back i broke 64 km/gallon on 2 tanks of 93 octane gas, spending about 90 percent of my time at greater then 13.5:1 AFR. DC GSR Hydro Tranny and 23.1" diameter tires inflated to 32psi.

around town i get like 20 percent less, even with the autox last weekend.

[email protected]

 

[downest]

I've had 54 mpg on stef's HF, on the trip to get my motor (so that's with a motor in the back). On my A6 in my old car, I got 44mpg on one tank, and consistently over 40 mpg for 1500 miles, while I was breaking in the motor last summer.

 

[Charles]

How can that possibly be? 40 mpg is like 25% better than spec. What wheel and tire size are you using?

 

[downest]

Stock at the time on my Si, stock HF.

 

[zulued]

i average 38-40 mpg in my 98 civic dx with the y7 on a highway trips i average 45-48 stock everything

when my crx was a stock hf with stock wheels i would average 45 mpg going to and from school and work. and i hit 60 once on a highway trip.

but as far as a stock si i woudnt know i never drove one long enough

scarponze

 

[mattminerDOTcom]

keeping my foot off the gas is hard, but thats how i got 40mpg plus even with a car with over 200whp.

[email protected]

 

[mattminerDOTcom]

also, i have no o2 sensors going into the ecu.

[email protected]

 

[Dodo]

I got about 40 or so with my dx, and now get about 35 or so. For a 91, i still think that pretty damn good.

 

[Ti Rider]

With my nearly stock '89 Si with it's original D16 I've never gotten close to 40 MPG. I've gotten 30 - 35 when I was putting lots of highway miles on it. But I get <30 MPG around town. I don't see any way a ZC could get close to 40 MPG.......

 

[downest]

I find that I get better efficiency on 55mph "highways" than on 65mph interstates. I think it has to do with the short geared Si tranny, and also that I usually do 75-80 on the interstate, while I stick closer to 60-65 on the smaller roads.

 

[bobski]

I hit 43.8 MPG (a new best) cruising at about 75 mph on a highway trip earlier this week. '91 DX auto with a D16Z6 and 195/60R14 tires. I guess slushboxes are only inefficient when accelerating.

 

[CrxCarl]

Well, once in Yellowstone with the future wife, I got 44 mpg out of my stock 89 Si.
Usually I would get 36-38 driving around during college in Chicago. And I did not take it easy on the throttle.