I'm thinking about building a 2L. I have most of the parts needed for the build. It will be 96mm,9550 raby cam with megasquirt. nothing crazy, it's a daily driver. I'm curios about the fuel economy.

What kind of mileage do you guy's get from your 2.0???

29 mpg with webber 40idf.

Left RRC with a full tank, and drove 208 miles to Draper Utah and it took 5.52 gallons to fill it again. 37.68 mpg on the highway cruising at 65-70mph.

Before I started having issues with my stock 1976 2.0, I was getting between 20 and 32 mpg depending on how hard I drove it and whether it was highway or around town.

29mpg when my 2056 was running the stock cam, stock FI, stock gears, 50 series tires.

Now with lower gears, 9550 cam, I can't stay off the gas so its way lower.

33.5 MPG on the 250 mi +/- stretch of I-70 between Grand Junction and Denver on the way back from RRC.

weber 40s and webcam-
Tuning REALLY influences mpg for me. When valves, linkage, balance, and the combo of 50 mains with 115 air correctors and 2.5 turns out on both air bypass and mix control screws all line up with the stars and planets, I'll get about 35mpg at a steady 75 mph, but only 20 or so around town. I could prolly get 25 or 26 in town with more restraint.
Recently got some crap in one of the carb passages and although performance seemed only moderately reduced (torque seemed low in mid-range RPMs) but it was sucking the gas big time.

I have a similar setup to what you want to build (except modified d-jet instead of MS). I average 24mpg if I drive conservatively. 20 if I am not so conservative.

With that set up and 8.3:1 (thats the recommended compression ratio for that arrangement) you should have no problem getting 30 MPG with stable driving and 25 wityh spirited driving..

Thats dependant upon the wear on your tranny, your tire size and how smooth of a driver you are..

I have had customers report 35 MPG from that cam set up in a 914, but the most I have experienced was 31 IIRC..

Stock 2.0 FI. Never really drive it in traffic, but normal use (50 series tires, canyon dancing) 22mpg. Trip to Moab (65 series tires, high speed cruising) over 30mpg, one leg 37mpg. Track weekend (200 mi RT to Willow, 1.5 hours track time) 20mpg. I do drive there with the 50's on.

Did I mention this is a great car? Cheap to run, race, maintain, and just play with.

20-25mpg driving somewhat like a normal person.

I certainly would question 35mpg or greater from a 30 year old car.

T

All the resposes aren't much different from what I am getting with my 1.7. I average about 25 mpg. commuting around town and to work (9 mi. one way). The motor is not exactly running perfect, I would think it should do better.

I'm running 195/60 tires, stock tranny and D-jet. I spins about 3100 @70 mph.

Is there a taller 5th gear for the 901 tranny's?

Its all in the combo..
I have have had many 100% stock engines get over 30 MPG in 914s with optimized tuning, most of the time even with mods the MPG stays up at that level or even more.

The engine in my 912E has now 107K on it after a build in 2002 to my best set up at the time. That engine, even today get 30-32 on average and thats after not having an oil change for 23K miles!

It has gotten a best of 40 MPG with a female driver, the best I have gotten with it is 37 MPG when it had about 20K miles on the clock

A fellow in the Netherlands that posts on the STF has gotten 36 MPG from his 140 HP 2056cc engine, follow this post to see the results.
Wally's post
He is a well respected tuner that has no reason to lie...

I won't even bother trying to explain how one of my Super 2 Liter builds is getting 45 MPG and makes 145HP... When I open the lid on that can of worms it'll be on my new forums :-)

The age of the engine has nothing to do with the MPG, its totally dependant upon the driving style, tuning and COMBO!

BTW- for many years I took care of a 912E that belonged to a little old lady that bought it new- she kept track of mileageand service like it was her only job.. One day while in her glovebox looking for the wheel lock I saw her mileage notes and looked at them closer.. It seemed the worst mileage she was getting was 36 MPG and a best of 44! I asked her about the notes when she came to get the car, she replied that that was nothing and after my tune up she had gotten 47 MPG before..

The next time the car came in my shop I made it a point to check the odometer with the old mile post method.. Hers was only about 1/10 off from the mile post...
She retired that engine with 321K miles on the original bottom end still getting over 30 MPG! Now I have it out back, as a parts car after it was totaled 4K miles after my full engine rebuild :-(

would this combo be the most efficiant 2.0 DD ?(96mm,71stroke)

I get about 20-25 mpg depending on how high my idle is that day (vacuum leak makes it vary from 1100-1600 at any given time)and if I have a loose valve and how much in town driving i'm doing.
I have a stock 2.0 with FI and drive the speed limit. (traffic permitting that I can even go that fast)

Its the best if you want something easy to create..

The "Best" so far in my experience has been the Super 2 Liter I have been working on for about 2 years now.. Its still a 2.0, weighing in at 2016cc, but it gains its displacement through a stroker crank and a smaller bore.. The combo is 78.4X90 and benefits from super intake velocities and excellent mixture quality. Couple that to a sweetheart of a cam and its a 40 MPG engine on a bad day.

I have one of these combos ready to go in the 912E as soon as the current engine expires, which may be a while..

I am building a Turbo version of this for my wife's convertible Bug.. :-)

Jake,
145hp is cool, but aprox what is the TQ? I know you don't want to "Open the can of worms", but can you just say over 100, 120, 500!!!! (I wish)

My dad swears he got 35 in his, and swears that it rean perfectly (ie: not lean). I have no reason to doubt that any 914 can get gas mileage that good. Why can't old cars get mpg figures that high. I mean, when the engines are worn they may get less mpg, but with a rebuilt engine to stock there is no reason you shouldn't get over 30 on the highways atleast with d-jet or carbs.

You guys haven't mentioned carbs before. Linda and Thomas are both getting over 40 on long trips. Linda got 49 at one point, but we had to change the dizzy trying to do better. Now the best she gets is 45mpg.
Dual singles.
:PERMAGRIN: Joe

We just had a thread about mileage...RCC I think was it. Many people aren't running stock tires and/or rims which throws off the odometer (and thus mileage) calculations. And remember, speedo offset is a percentage error, NOT a linear error.

Tq was 153@ 3,500

BTW- when my car topped out at 40 MPG it was carbureted :-)

Another reason our cars get higher mileage than might seem likely is the tiny frontal area. CD isn't so great (.36 or sumthin), but there just ain't much car there anyway. I wonder how much resistance (and maybe lift?) is generated by the rear valence. I've considered cutting sime "releif" slots even...

The 2007 Honda Fit gets 38MPG average HWY.

If people can get more than that using 30 year old technology, they should be very rich - IMHO.

Cheers,

T

Sure. But then you consider that the Fit weighs a lot more then the 914, is loaded with airbags and other tech that was not even around 30 years ago, etc.

30+ mpg is not something that is new. Old bugs got 40+mpg regularly. Cars were lighter and had much smaller engines. In Europe, this still holds true.

Today, most of those cars would be considered "underpowered death traps," and with every soccer mom in an SUV talking on her cell phone that may well be the case. But, its a lot easier to have a fuel efficient old car (so long as its not an american V8 land yacht) then it is to have a modern efficient car with 27 airbags, loads of sound deadening, AC, etc.

Zach

How do you figure out that error? I do know that my speedo reads 5mph slower at 65mph.
But what about the odo.??

Use the milepost method. set the odometer at a mile post and see what it says when you get to the next one..

I do it over a span of 10 mile posts to work out the margins for error a bit..

My figures are with a GPS. Still no control on how full you fill the tank each time, but over a few tanks it will work out. Simple non navigating GPS as low as $50 now will tell you actual speed, average speed, and miles driven. Cheaper than speedo/odo recalibration. Be a big spender.

I'm running stock rolling diameter size tires, so my gas miliage should be pretty accurate (minus vacuum leaking causing unsteady rpms).
People keep asking me why I run such big tires.

I know on I-5 there are speedometer check sections where you zero your odometer at the starting sign, travel five miles (there are signs along the way) and at the last post (the five mile mark) you look at your odometer. It should read 5. A larger number (meaning smaller wheel diameter) or smaller number (meaning a larger wheel diameter) indicate your odometer/speedometer are inaccurate and thus ALL mileage calculations.

Another way is to measure the time it takes to go from one mile marker to the next. Not quite as accurate since you're relying upon a human to start/stop the stopwatch (get a trusting passenger to do it). Just keep a steady 60mph and start timing when you hit the first mile marker. Stop timing when you hit the next mile marker. Your stopwatch should read 60 seconds. Again, above or below that time indicates a speedometer error -- remember, an inaccurate speedometer reading will also indicate an inaccurate odometer as well.

To get a 'true' odometer value for calculating mileage:
First, know your error. This will be a percentage e.g. 0.95 :
Error=OdometerReading/ActualMiles
This becomes YOUR speedometer offset -- technically it could be used by someone else with the same wheel combo but it's best for them to test their own vehicle. All odometer calculations will use this error %.
Second, calculate true distance traveled (in miles):
TrueDistanceTraveled=OdometerReading/Error

Example:
OdometerReading = 5.25 miles
ActualMiles = 5.00 miles
Error = 1.05 or 105%

Given our error % we can now calculate our true mileage or speed:
OdometerReading = 100 miles
Error = 1.05
TrueDistanceTraveled = 95.24 miles

Mileage = TrueDistanceTraveled / GallonsOfGas
GallonsOfGas = 3.5
Thus Mileage = 95.24 / 3.5
Mileage = 27.21 mpg

Assuming we didn't correct for speedo offset:
Mileage = OdometerReading / GallonsOfGas
Mileage = 100 / 3.5
Mileage = 28.57 mpg

To get speedometer error:
Error=Reading/ActualSpeed
To get true speed:
ActualSpeed=Reading/Error

My car is my DD and I see about 20 around town and 25 on the highway(>60 MPH). That is accounting for my 50 series tires. I do drive my car like its a Porsche, not a VW. Stock 2.0 with a stock replacement K&N and a Triad muffler.

I have a stock 2.0 except with 8.0:1 euro pistons. I'm running 205-50/16 tires and I get 23 mpg in the city. I get about 32 on the hiway. On the race track with 205-50/15 tires, I get 9 mpg.

Rick

And she reminds you of how fast you really went.

Howard was doing the MPG for Linda and myself on the Route 66 run. Linda first got 42 then 44. Myself, I was getting 27, but Howad was getting 25 in the Carerra. I know that Lindas car tuned for MPG will beat 32 around town. She can get over 50 if she puts in some effort. She got 49.16 over 295 miles. Parker, Az to Huntington Beach, Ca.
:PERMAGRIN: Joe

My old 1.7 d-jet got around 35 mpg combined driving. after they mandated oxygenated gas in my area, the milage dropped by about 4 mpg. Just as predicted by the State, which told us to expect a 10-15% drop in milage, risk of fuel leaks in "older cars", and a higher price at the pump. Experienced simular drop in mileage in my Bug, and Ghia with the "better" gas. The better gas had MTBE in it, which is now being banned as a major pollutant. Gee wiz, wonderful politicians telling us what to burn.
Now the farm interests are pushing corn alcohol, wonder where that may lead????
at any rate the type of gas used needs to be considered when comparing mileage figures. else its a apples an oranges comparision. i believe the oxygenates are also seasonal in some parts of the nation, your milage may vary with the gas you use. If you see a 10-15% difference in milage, it may well be the type of gas unless you know it was the same stuff