ok my 89 305 has got me scratchin my head lately.

since gas prices have been down ive been running premium
then ill reset the trip odometer at a fill up then go till im at the bottom of the red L line at e and my trip will be anywhere from 290-340 miles! how can this be?

my odometer so far has never been below 250 at a fill up an thats when im geting donw on it more and i mostly drive city. but im averaging about 55-60 mph....lead foot

once i hit open country roads im 90+ mph but thats on rare rare occasions since its winter

and on top of that this is NOT a low mile car by far im at 285,000 miles.. ive put roughly 6k miles since i bought it because it runs so good...if you ignore the damn check engine light when it comes on it runs better lol

 

When I'm driving my IROC-Z I get about 22, 23 mpg- I had it all figured out in metric but that's useless to you isn't it? I did a test once in which I drove 186 miles at an average of 85 mph, I got 21.75. That is slightly skewed because I got stuck in a 45-minute traffic jam right after I filled up, so in actuality it would have been a bit higher than that.

You should be going pretty close to 300, 350 miles on a tank, I think, depending on your driving style, conditions and such.

Since that's about what you're doing, I gotta ask what's the problem?

 

300 miles on 15.5 gallons (a full tank from full to completely empty) = 19.3 mpg. At 340 miles = 22 mpg. But, you're not draining the tank completely, so you would be getting slightly less than that figure. I don't think you're doing your math correctly.
BTW, on a recent road trip, I got 26 mpg with my 91 305 Camaro, while averaging 75 mph.

 

Yeah, my 92 RS 305 with 187k gets incredible mileage on the freeway...about 25-27 mpg. Blows me away! In town....forget it....about 12 mpg. The price we pay...I can live with it!

 

My 89 RS 305 w/ 5 speed 83K miles makes around 32 city/highway (my hometown is based around a highway so your normally doing 45 everywhere lol) and I have a lead foot lol

 

well ive been basing everything on 3/4 of a tank


...somehow i came up with like 28 mpg but i think it may be wrong.


so using 3/4 of a tank i get average of 300 miles and sometimes 400 if i drive normal
ive been figuring 14 tank~ roughly 3.3 gal as i was told the tank capacity is 13.2gal


whats the capacity of the tank?

next thurs ill start fresh filling the tank and driving at my usual pace and then post the info and my results

 

Should be a 15 gallon tank.

 

My guess is this guy dosen't know how to calculate his gas mileage. Math skills went south in a hand basket lately .

 

You can't calculate gas mileage going by 3/4 tank. You need to start from full, otherwise it's an inaccurate guess.

 

lol between being sick as hell. having my midterms coming and 3 english essays due and having to study for my technical mathematics exam my mind is prety much burnt out at the end of the day.

i re did the calculations this is a guestimate as im going only by 3/4 tank leaving 1/4 unused and got around 18mpg this week and thats reasonable since ive been doing lots of slow city driving matting the gas off every street light nearly