ROCKET JO

What kind of mpg should I get with a 1985 delta 88 307 auto fresh tune up low miles-40k ciry and hiway??

J-(Chicago)

20 highway
16 city.

about.

J-(Chicago)

Let me know if you get or have this car.
I have had and still have many 80's Deltas.

Redog

I got about 16 city/hiway, before a tune up, after about 19 cit/higway, until I took out the 2.73's. But it still got around 15 cit/hiway with the 3.42's

Olds64

I think that is reasonable mileage and decent for an older car. That is about what I was getting when I had a 90 Buick Estate wagon with the 307. It was essentially the same car as an 80s Delta 88, just a little bit bigger.

J-(Chicago)

Yeah, mine gets about 9 mpg at the moment though, with the carb and timing the way it is.
I'll be on my 3rd rebuild this weekend.

Olds64

J, don't forget to have the throttle plate bushings redone. You also need to seal up the bottom part of the jets with a fuel proof compound. Good luck. 9 mpg is a bit more normal for an older muscle car.

84oldsDelta88

wow i actually get 18 mpg city and 25 highway with my 1984 oldsmobile delta 88 307 v8

zed

Canadian gallons ,right?

Redog

What gears do ye in the rear? I'm guessing 2.56's

Toro68

My 1985Buick Rivreia , that has a 307 OLDS motor- get about 24mpg

84oldsDelta88

no its u.s. and it was a type not 25 highway i wish i think im around 22-23 still ok for a v-8



im not sure. im still trying to figure out my tranny the shifter indictactor is PRND2L but i clearly hear 3 shifts 1st to 2nd 2nd to 3rd 3rd to 4th so if i do have a 4 speed it would be the th 200-4r with OD. but wheres my OD selector on the dash? unless the previous owner changed the transmission without changing the gear selector. is 2.56 the stock differentail?

Lady72nRob71

The 3-4 "shift" you hear may be the torque converter solenoid kicking in at about 40-45mph. My 86 Cutlass with a 307 does this, but I do have the OD tranny. Almost feels like a "5th gear". 18 city and 25 hwy is about right for mine.