Gear Ratios?

[pygmypony]

Been wondering about gear ratios as I prepare for an SVO 5spd and rear swap into my 86 coupe. Right now I think I have a 3.33:1 ratio in the 7.5 rear end. Is that right?

Also, the SVO I believe has a 3.7 rear gear and a .73 OD? I'm trying to figure out the effects of ratios on the car before I go gung ho and swapping parts. I'd even try a shorter tire to help balance out any disparity

 

[Red_LX]

Is your car a manual?

I'm not totally sure about the pre-87's, but I'd venture a guess that your car probably has the 3.45 gears in the rear (those were standard issue behind the manual trans in Mustangs and Thunderbirds for several years)

SVO's had 3.73 gears (same as 5 speed 2.3L Mustangs), but they had different transmission ratios than other 2.3L cars. .78 OD, according to this chart, which is pretty handy: http://www.fordmuscle.com/archives/2000/09/t5swap/index2.shtml

My TC has 3.55's in it (of course, 8.8 rear) and I think they're about perfect behind a 2.3T.

 

[Anlushac11]

I think your going to be fine. SVO IIRC had 3.73: 1 gears and with 5th gear it should get snappy acceleration and yet still get good economy in 5th.

Heres some siites I have bookmarked that might come in handy for you

http://www.ricksontruck.com/calculators.html

http://www.miata.net/garage/tirecalc.html

 

[pygmypony]

my favorite is http://www.dakota-truck.net/TIRECALC/tirecalc.html

and using the chart with the correct OD ratio, I've got the final drive UP to 3.01:1 with 245/45R16 tires! About 3:1 final drive is where I'd like the car to be for its dual purpose setup.