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Opel Adventure # 77 NC
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648 Posts
Discussion Starter · #1 ·
Does anyone know what the mileage should be for a 69 Kadett wagon w/ 1100SR & automatic?
On a recent trip to Chicago ~300 mi round trip, I got about 24 mpg :confused: . I really expected to get closer to 35, traffic was relatively light, and speed was around 70 mph.
The carbs have been adjusted per FSM, as well as timing, and valve clearance. It has new tires w/ 31psi all around, and only about 20k total miles. I am also using new K&N air filters.
Any ideas?
TIA
Kevin
 

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Old Opeler
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5,564 Posts
Sucks Gas!

Some manual Kadetts have been reported as getting 35 to 50 mpg so I guess the automatic is having a big effect on gas milage - that and pushing a "brick" (Wagon!) through the air at 70 mph! Best gas milage is usually achieved at 35 to 45 mph - also how big a load did you have in that poor wee Wagon?
 

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Opel Adventure # 77 NC
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648 Posts
Discussion Starter · #3 ·
GTJIM
Not too much of a load, just my daughter, me, and the 13" aluminum slots I picked up in Chicago :D .
I am also running w/ Pertronics!
Kevin
 

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Member
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2,054 Posts
Are you sure you had the transmission in "D" and not "3"? 24 mpg just doesn't sound right. Were the windows rolled down?
 

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Old Opeler
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5,564 Posts
Winter!

West Coast GT said:
Are you sure you had the transmission in "D" and not "3"? 24 mpg just doesn't sound right. Were the windows rolled down?
"Were the windows rolled down?" In mid-winter on a trip to Chicago! :eek:
He ain't in California !! :D
 

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boomerang opeler
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5,636 Posts
West Coast GT said:
Are you sure you had the transmission in "D" and not "3"? 24 mpg just doesn't sound right. Were the windows rolled down?
wow opel must have been leaders in the field :eek:
that might be "D and not 2nd" :D

and whats more invigerating on a crisp winters morning than insticking your arm from the window rail :D
 

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boomerang opeler
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5,636 Posts
the answer to all our gas milage problems
go to evil bay and put up item

7949085068

i think i will get 10 and put them on in series should be good for 400 bhp!!

well you've got to beleve haven't you :D :D :D
 

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Opeler
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86 Posts
Sounds like a driving opportunity

Opels are funny creatures. When my father bought the 1100 Kadett two-door coupe back in 1981 from the original owner, it was not uncommon to get upwards of 43 mpg. However, it has a four-speed and was the two-door version of the Kadett 'B'. It would sip gas and run like a banshee.

On the other hand, he was always perplexed and puzzled why his '70 GT would consistently get 32 mpg, but the '69 GT could at best manage 26-27 mpg. Same body styles, engines, carbs, four-speeds, etc. Identical mechanically in every way! Both cars ran Solexes, etc. Driven under similar conditions, the '70 always was slightly more economical. He probably never did unravel that puzzle, as the challenges of raising a couple of teenage boys 30+ years ago kept him otherwise distracted!

My guess is that if you were to go through the fuel system from the tank to intake manifold, you might discover the odd leak here and there, which is likely contributing to the reduction of mileage. The 1.1 ought to be delivering better than 24 on the highway.

The fun part is that you now have a bonafide opportunity to get the car out on the highway more often to confirm your efforts! Good luck!!
 

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There are probably a few contributing factors here. First off the aerodynamics, or lack thereof. Secondly, the automatic tranny will not only rob hp (about 15%) through driveline 'slippage' (hydraulic coupling, not a true mechanical coupling), but it will also effectively change the final drive ratio to the point that the rpms are essentially 300-400 higher than a comparibly geared 4-speed model. Third, the actual gearing in the vehicle may be as high as 3.89:1 or 4.10:1, which is not very good for economy!

Bob
 

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Your '69 11SR A/T Model 39 wagon

RallyBob said:
There are probably a few contributing factors here. First off the aerodynamics, or lack thereof. Secondly, the automatic tranny will not only rob hp (about 15%) through driveline 'slippage' (hydraulic coupling, not a true mechanical coupling), but it will also effectively change the final drive ratio to the point that the rpms are essentially 300-400 higher than a comparibly geared 4-speed model. Third, the actual gearing in the vehicle may be as high as 3.89:1 or 4.10:1, which is not very good for economy!

Bob
Just looked it up in my '69 FSM and your 1.1SR A/T wagon (Model 39) uses a 4.11 rear end, the only one offered, BTW . . . real peppy around town and from a stop light, but AWFUL for highway gas mileage! As Bob said, coupled with the slippage in the non-lockup torque converter, it won't ever make very good mileage. Just curious, but what RPM are you turning at 70?

On another note to all the TH-180 drivers here, does anyone know of any GM lock-up torque converter from a later model that would fit the TH-180?? :confused: RBob?
 

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Opel Adventure # 77 NC
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648 Posts
Discussion Starter · #11 ·
Yes the windows were up,and the trans was in D.
Not sure what rpm it was turning, but it is made to reach the rated HP @ 6000 rpm. I may have to put in a tach to see just what it is turning.
I guess I will have to take a closer look at the carb adjustments, and make sure all the hoses are good.
Anyway, winter is not the optimum time of year to worry about high mileage.
later,
Kevin
 
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