What does it even do…i want to get a differtn shifter but it will take away that button…shouldi worry about loseing it?
overdrive is the fuel saving gear
it gives u almost no acceleration but good fuel economy
when it is on it does this?
i have an idea…
get a 5spd swap along with that new shifter. 
No worries about an overdrive button that way!
on the auto 240 (it is 4spd AT rite???)
it has 3 gears which the gear ratio is lower then 1(0.xxx)
and that ratio give u mechical adventage, so the engine don need to work as hard to move the car, but doesn’t give u as much spd…
and the O/D gear(4th gear) has a gear ratio over 1(1.xxx) which let u maintain at teh spd w/ less effort, but doesn’t have too much accelation…
when the O/D is on the computer let the tranny to shift up to 4th to give u gas mileage… when u locked it(O/D off) the computer will only let the tranny shifts up to 3th and holds it there…
this happens when u puts it in 2 or L as well…
it just holds in the gear…
neways…
this is a bit off topic…
does neone have a gear ratio chat for a S13 MT tranny???
i just wanna know if the MT tranny have O/D too
well i think it does, but just wanna confrim…
MT Gear Ratios From The s13 Factory Service Manual (Download It!)
1st 3.321
2nd 1.902
3rd 1.308
4th 1.000
5th/OD 0.759
Reverse 3.382
Intresting…anyone know the ratio for the auto trans?
o thx…
and damn i messed up on the gear ratio thing…
hahahhahahhaha