[L20068]

What are the 3.20s that my Mustang is equipped with? Just wondering.. I've heard "311s" and "373s" and "411s" and "278s" and such, but I have never actually heard what each gear ratio's purpose was.

 

[2bav8]

Gear ratio, its the amount the driveshaft will turn before the rear wheels will turn. Think of it a lot like the gears on a 12 bike. If you have a big gear in the back, its a lot easier to pedal right... but you can't go as fast as you can only pedal so fast.

Gears like 4.11s and 4.86s are for drag racing. The allow the engine to rev quicker and hence the car will acclerate quicker, but at the expense of higher engine rpms. This is because the engine doesn't have to strain as much to turn the rear wheels. Just like trying to take off on your 12 speed bike, its a whole lot easier in low gear as opposed to high gear.

Gears like 2.80s, 3.20s are the opposite, they are better suited for the street. The engine won't rev as fast when trying to acclerate, but you also will have less rpms when crusing on the freeway. You'll notice better fuel milage because of this.

[color:red]1966</font color=red> [color:blue]V8</font color=blue> [color:red]Coupe</font color=red>
http://www.geocities.com/2bav8
5 speed, 4.11s, 10.13 in the quarter mile.
Oh wait, that was a Sammy Haggar song...

 

[L20068]

Interesting, then, that I am (all of a sudden seemingly) only getting 10 miles to the gallon. I get MAYBE 160 miles to a 14 gallon tank... With a 1 barrel carburetor.

 

[grabberblue]

Your wheels will turn 3.2 times for every 1 turn of the drive shaft.
You are only getting 10mpg? What engine-trans do you have?

John


[color:blue]66 coupe 289 2v C4 needs restore</font color=blue>
[color:blue]70 coupe 351W 2v c4 almost done (?)</font color=blue>
[color:red]71 coupe 302 2v C4

 

[Guest]

Close...you just got it backwards John /forums/images/icons/wink.gif

[color:blue]'68 Coupe
250/C4, 221 Argentine Head
Breakaway Converter, 9", 3.50's/T-lock</font color=blue>

 

[L20068]

Its a 200 cubic inch L-6 mated to a C-4 automatic. I used to get about 25 miles to the gallon, so I don't know what's going on...

 

[DENVER]

THE GEAR RATIO ISN'T YOUR PROBLEM IF IT AT ONE TIME YOU WERE GETTING 25 MPG AND NOW YOUR NOT. YOU NEED TO LOOK CLOSE FOR A FUEL LINE LEAK. CHECK YOUR OIL AND MAKE SURE IT'S NOT OVER FULL. SOMETIMES THE FUEL PUMP DUMPS THE GAS INTO THE CRANK CASE. DENVER