hey guys long time since i posted something....i have a slight problem, i have a 69 stang with an auto c4 transmission. I dont think the last gear is kicking in as when im driving 60-70mph it seems as though it would need another gear. i count the gears as it changes when i take off, i only count 3. dont know what to do....

 

Hiya
the C4 only has three gears. the last one of course being 1:1. and yes with a pretty normal rear axle and rear wheels you'd love another gear at 70

tell me the rear wheel tyre size, axle ratio (3.2:1? 3.5:1 ...) and i'll tell you what rpms you'll do at 70mph
if it's a stockish car it will change gears at around 60mph into the last one when flooring it. engine wouldn't survive 70mph in 2nd unless you changed rear axle ratio or have a 6500+ rpm engine. sounds perfectly normal .... american cars in the 60s weren't made for german autobahns ... ;-)

 

is there a way i can prolong the change in gears? meaning could i adjust the the way they change? i know when i removed the tranny there was a screw on the tranny that for some reason i think did that..

 

the car is all stock and i have 17's all around

 

no. the gear ratios are fixed. that's why so many people use eiter an overdrive tranny (AOD), or a manual T5.
give me your door data plate codes and the tyre size (not the wheel size). something like 255/40R17 or similar

 

by having no cable on the kickdown, what is this actually doing? is this preventing from having a higher gear and running on a low?

 

it prevents the trans from downshifting. in a passenger car if you go 50mph cruise you will be in 3rd gear. when you stomp the pedal (for example to overtake), the cable will actuate a valve in the gearbox which will cause it to downshift.
So in reality it should automatically shift into 2nd gear and when the revs are high (at around 60mph) shift back to 3rd

if the cable is missing it probably won't do that. bhowever i'd prefer someone who kows automtic gearboxes chimes in. i don't know anything about them. i'm manual myself

 

You are also not getting the pressure that is required by not having it. With it, you'll get higher shifts and by screwing your modulator in, that will also increase your rpm shift and firm them up. Don't go more than 3 turns in though.

 

Adjusting the modulator is only going to change the point the 3rd gear applies. Instead of shifting at 30, it may come in as late as 40. That won't do anything for the rpm's that you are turning at 70. That will be the same. You probably need a taller gear in the rear.