Gas Mileage & Final Drive Ratio

[Radical540]

I'm looking for a consensus to see what kinda of "average" fuel economy I should expect to see on my '93 ATX??

Also, does anyone know what transaxle final drive ratio is in these cars-- or where I can find that info?

On both accounts, mine seems to simply not get the gas mileage I would have expected. Someone told me that the final drive ratio was "bumped up" when the ATX was introduced into the SHO.

Any insights??

 

[FastAndFurious]

Final drive ratio is 3.77 for atx, and I think you should be getting 25+ mpg on freeway and about 20 city driving.

 

[Radical540]

Final drive ratio is 3.77 for atx, and I think you should be getting 25+ mpg on freeway and about 20 city driving.

3.77 feels about right. She really gets up and goes from a dead dig.

20 city would probably be a stretch from what I'm seeing. Although, I'm not working with entirely accurate figures; since I've never completely driven the car "dry". But when I've gotten close to what I feel is ragged 'empty', the mileage figures are looking more like 17-19. And I haven't driven the car enough on the HWY to get an accurate HWY mileage figure.
I found this link from a gov't mileage report: (warning-- it's pretty somber)

http://www.fueleconomy.gov/feg/noframes/29005.shtml

I used to see mileage increases of up to 5mpg by adding 4ozs of acetone for every 10 gallons of fuel. Guess I'll have to try this out with the SHO.

Also, acetone is a good additive to negate the ever so harmful effects of ethanol in gasoline!!!

 

[Phokus]

yay! V8 gas mileage!

Well I've been using fuelly to keep track of my fuel expenses
http://www.fuelly.com/driver/waldo (click on the car for detailed info)

for my SHO I get around 17 or so in all city and mid 20s with a best of 28 of all highway. which is not too much better than getting ~17 city and 24 highway in my Vic
But then again I have a MTX

 

[Radical540]

I hear ya. Thou I think my Z28 gets better mileage than the SHO on the HWY (although my Z28 only has a 2.73 final drive ratio)-- but I attribute that to the extreme aerodynamics of the Z28.
All in all, at least it's better than the 3 gallons-to-the-mile that my Chevelle gets.

Cheers!

 

[TwistedD85]

Don't need to run it dry to get accurate figures anyways. You'll never have accurate figures, the gasoline itself changes the weight, the air temperature and density will change how it delivers the fuel, a ball park figure is about all you're going to get. I usually get like... 16 mpg, 15 now that the cool air is rolling in, I need to get it fixed. Oh and this particular forum is merely for archiving the How-to's, it'd get more attention elsewhere

 

[vortex2450]

My 93' with 215k, super sucky tires, some front end suspension woes, and in need of a 60k gets a consistent 25 MPG combined with some intermittent throttle stomping

When I'm being a better and more cautious driver I snag 26.5 mpg combined

On a straight highway run a managed 27.8 mpg while feathering it.

I do get ~ 22 mpg in the city which is pretty good.


Once I rebuild that engine and tranny and re work the suspension I am expecting better numbers.

Hope that helps.

 

[auto.guru]

3.77 feels about right. She really gets up and goes from a dead dig.

20 city would probably be a stretch from what I'm seeing. Although, I'm not working with entirely accurate figures; since I've never completely driven the car "dry". But when I've gotten close to what I feel is ragged 'empty', the mileage figures are looking more like 17-19. And I haven't driven the car enough on the HWY to get an accurate HWY mileage figure.
I found this link from a gov't mileage report: (warning-- it's pretty somber)

http://www.fueleconomy.gov/feg/noframes/29005.shtml

I used to see mileage increases of up to 5mpg by adding 4ozs of acetone for every 10 gallons of fuel. Guess I'll have to try this out with the SHO.

Also, acetone is a good additive to negate the ever so harmful effects of ethanol in gasoline!!!

http://www.snopes.com/autos/techno/acetone.asp

acetone in the gasonline is a hype. if you want better mpg, look at your engine and how to increase its efficiency. Run 87 octane and not 93, makes your engine burn warmer, and more cleanly. Change your oil more often, and reduce engine friction.... things like that

 

[SuperHO]

pffft....want fuel economy? Buy a 3 cylinder Metro. The SHO is meant to drive, not putter around trying to get high mpgs. If you're seeing anywhere near 20mpg, you're doin it right.

that said, my 95 MTX averages around 24mpg, mostly city, with frequent runs through the RPM range.

 

[auto.guru]

^ agreed