It is my experience that unless people keep an actual log book you can't
believe their gas mileage claims.

==> i agree 100% with what you said. now, here's a different tale....

background - in the 70's and early 80's, i owned 6 opel cadet autos.
they are like volkswagens, in the sense, that they pretty well get the
same gas mileage, regardless of vehicle. the 70's were not known for
fuel effecient engines either.

my gas mileage was around 21 mpg, with the very best i could do was 26
mpg one time.

basics - in automotive class, they would constantly say that the
air/fuel ratio is 14 to 1. so, how do you get better mileage if this
is the standard ratio that engineers build the gasoline engine on???

experiment - opel cadets were the cheap end of opel and there were
only three major problems with them. the clutch was made out of almost
paper material and would give out at around 50k miles. the rear end
would go bad in them, but couldn't put a mileage on how much wear you
could get out them. but the carburetor... oh, the carburetor sucked
the big one.

it wouldn't hold a repair but about six months. and the kick in the
pants was that you only had two options. buying a rebuild kit for 8
bucks and doing it yourself, or pay 275 bucks for a new carburetor.
after about 3 or 4 rebuild kits, you would have to throw the carburetor
away and get another used one.

one day at the junk yard, i was talking with the owner about how nice
it would be if they made a carburetor that last forever and doesn't give
out. he reached over and gave me a vega single barrel carburetor and
said that he NEVER gets a call for them. said to try it out and see if
it works.

so, i went to the local machine shop and we built the adaptor plate to
mount the carburetor on and even with the original vega air filter, it
would all fit under the hood with no modifications.

i had installed this on a station wagon. the rear end had gone out of
it and i had installed a GT rear end with 4:11 gears. so, my gas
mileage wouldn't be the best.

the results - i kept a 15,000 mile log book. EVERY drop of gas was
logged in.

no other modifications was made. no timing adjustments. just the carb
exchange. the car always started quickly and not like it did before,
where you had to prime the carb to get the engine to fire up.

this car averaged overall 28.6 for the 15k miles. far better than the
best day with the original carb. the highest i ever got when i was
keeping the log, was 34 mpg.

one time - i filled the car up and drove on the interstate to teach
class 60 miles away and ran it 75 mph on the interestate, up to class
and after class - was riding in the cradle between two truck drivers on
the way back at 80 mph and when i got back to the same gas station, i
filled up the tank to the very top and figured the gas mileage. was
expected a big drop because of the type of driving that i had done. it
came out at 32.8 mpg. the next fill up average 31.9 mpg.

so, what's the final verdict???

my conclusion is this.. if i can change the carburetor and not modify
anything else on the engine and get a 25 to 30% jump in fuel economy, i
say that something is wrong - somewhere.

and to further check this out. i built THREE MORE of the same set ups
and put them on standard stock opel engines and got the same results.

the downside - you better pack a lunch if you want to pass. the
engine would accelerate, but it was a constant slow ramp up time, but it
did not ping.

anyway, that's my story and i'm sticking to it.

~ curtis

knowledge is power - growing old is mandatory - growing wise is optional
"Many more men die with prostate cancer than of it. Growing old is
invariably fatal. Prostate cancer is only sometimes so."
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