So I've been wondering something about the L15
 

Ever since the 1st FIT hit our shores, I wondered why neither version of the L15 isn't as frugal on gas as one would think. I mean the old D16y8 from 93 to 01 civic was VTEC, made more power (124-127hp), and got 30city/34hwy. Then you have the heavier '14 civic with 1.8 liters (140hp) getting 32city/39hwy. Even the '15 just squeezes those same number.

So I segway to my question at hand. WHY? Could it be that the gear ratios the the fit has is to keep it near or on its "sweet" spot. I don't really care either way. I'm content with what I bought. Just thought this would make for good conversation.

Those are the old epa numbers. They changed the test and the new results are lower.http://www.fueleconomy.gov/feg/findacar.shtml has revised numbers for old models.

The 1997 EX with D16Y8 engine was rated 30/36 but is now revised to 26/33.

I would doubt a new civic can get 40 mpg hwy or 39 for that matter. It probably gets 34 at best. But aerodynamics plays a big role for the Civic and again the Fit.

It actually gets better. My mom has '13 Civic EX-L w/ Navi. We drove to Charlotte. 190mi each way. She got 45mpg. I had her use 93 octane though. She drove 70-75mph.

I always thought the first gen had a poor power to weight ratio, thus MPG wasn't as expected. I had an '86 Civic Si hatch, 1600 cc, 5 MT, and I got mid 30's all the time on hiway. I have gotten as high as 40 MPG with my '13 Base 5 MT, but it's almost like, OK, 28 years later and MPG is not that much better.

If I'd compare the Si to the Fit, then Si was lighter, 1600 cc engine Vs Fit's 1500, 91 HP in Si Vs 117 HP in Fit. Both seem to have the same final gear ratio, as both do about the same RPM at 70 MPH. I'd think that the Si had a better power to weight ratio than my Fit. ?

I dunno, what is the best power to weight ratio for a car to get both decent acceleration and good MPG? The '15 Fit is on the right track, but what would it take to get 50 MPG outta the Fit?

I too have pondered that for years. My brother-in-law has had 2 Civics (current one a 2010) and he continues to outpace my Fit. He isn't fibbing either cause I have driven and measured the mileage myself.

Tend to agree. Its gotta be the cd design of the GDs and GEs.

Check out a fellow FF's (ODIE) actual experience with his brand new 2013 FIT A/T:

50 MPG!!! That is stellar for something that's EPA rated at 34MPG Hwy.:bowdown: He's got interesting articles too!!!

The Fit/CRZ/Insight's motors are big stroke tiny bore motors (we outstroke a 350 chevy)

In order to get more efficiency out of or motors, we really need a bigger bore and slightly smaller stroke, so that we dont have such a massive frictionloss.

For now, I run a Zinc oil additive that so far has proved itself to make the motor quieter and for the first 2 tanks of gas have gotten better gas mileage.

Measuring out 3 more tanks before I can trully classify it as an improvement because of the additive or because it has fresh oil!

Usually and in most cases a smaller engine revs higher, and also to give you the power you demand. Like the Prius for example; it has a 1.8L, heck they could go smaller but that would REDUCE fuel economy, so they went with a 1.8 because it revs lower and has a beefier torque band.


Our gearing isn't helping either.

You are aware all honda motors rev high. L15 rev limit 7000rpm, Civic SI K24 7200 Rev Limit, Acura J-series 3.2/3.5/3.7 rev limit 7000. Toyotas have never revved hi. the Civic LX/EX's R18 rev limit is 7000. Apples and oranges bro.

The issue is gears and final drive ratio. But if they lowered it, it would mean slower acceleration. I'd prefer the ratio's Honda chose over the other car makers choice for their sub compacts. 1st/2nd fits have better acceleration times compared to others boasting more hp.

1. New Civic has a bigger motor, more torque, more power can hold cruising speeds at a lower RPM effectively.

2. Old Civic has none of the emissions requirements or restrictions cast upon the new Fit as a ULEV vehicle. Can make more power and also weighs about 250 lbs less at minimum. VX and CX are almost 500 lbs lighter than the Fit.

Like PaleMelanesian wrote, EPA numbers for old cars have been revised.

The fact that the L15A7 can put out 117hp out of a 1.5L single cam with a bunch of emissions requirements is actually pretty amazing. Not to mention with a much better power/torque curve for daily driving than the old D series.

Besides, look at a GE next to an old Civic and it's a massive/tall car in comparison. I'd say Honda's done pretty well to keep the spirit alive in the Fit despite increasingly stringent EPA and NHSTA regulations.

I was just using Toyota as an example, what I was trying to say was about engines in general, and the common characteristics that come from having a larger vs smaller displacement.

The gearing is just fine. Just because toyotas dont rev high, doesnt mean they suck. My old camry was a 2.2 liter 5sfe. it revved to all of maybe 6k rpm.

That old boat still managed over 35mpg

Toyota engines are awesome. My Corolla was bulletproof. Got as good of mileage as my Fit, and never had issues. Really, Honda or Toyota, you can't go wrong as far as reliability and fuel economy goes.

my 96 civic with the d16y7 engine tends to disagree with those numbers by quite a significant amount every day. i get anywhere between 31 and 32mpg city and between 40 and 43mpg highway. since i have the DX i tend to equate that to the DX having the tallest gearing out of the majority of the trim levels lol

Ah, since it's a 96 DX the revised EPA rating is 28/35. I know, that's what I drove for nearly a decade. :D And yes, it's capable of well above the rated numbers. We just need to compare apples to apples (new epa to new epa).

The first gen had a fairly solid variance between the manuals and AT. My manual routinely gets mid 30's in mostly city driving and doesn't get below 31 with even spirited driving.

I can believe this. The auto seems to be tuned for a sportier feel it seems. It holds gears longer, revving higher, etc.

Using the paddle shifters and shifting manually helps me score about 2 mpg in city driving.