going from drum brakes to 4thgen 12" disc brakes on a3rdgen other then a proportional valve do you have to change master cylinder too and if so can you use the 4thgen donor's car master cylinder

 

hmm I must not fit in here

 

@#$%^&*()_

 

Way too big of a question.... kind of like asking "how do you replace a motor, step by step with pics and a parts list" and then wondering why there's no responses, when you don't tell what motor you have and what you want to put in....

Yes, you have to change the master cyl & prop valve. I have no clue whether the 4th gen stuff will bolt to a 3rd gen. There are 3rd gen parts that will work right, but since we don't even know what year car you have, we can't say whether you have them or not, or what you need to change. There's all sorts of detail differences, the nastiest of which is the fitting sizes (SAE or metric).

 

first of all all 80's cars are metric right second the rearend will fit yes it's wider then the 3rdgen but 4thgen rims will take care of that just thought i seen a post here that i cant find now about the swap

 

well now have a 97 TA discbracke booster,master and factory proportional valve maybe it'll work

 

82-83 were not metric. I know, I have one. I had to make an adapter to put a 91-92 rear in my car.

84-up were metric. In case yours is one of those, at least you won't have to dodge that bullet.

Good luck, let us know how it turns out.

 

sorry Rb i have never clamed to be the sharpest tool in the shed DOH! its a 1984 berlinetta digital and electronic everything hell even the little 2bbl carb has 200 wires running to it.Well my son ist putting in a 13"disc in his 94TA and he is giving me his 12" disc setup and i really did not want to get involved putting a manual proportional valve in so that is why i am here (hehe ifen ya dont here from me again that means it didnt work and i am prolly stuck upside sum tree sumwere )