sr5 to gts rear disc brakes

[drozy88d]

I recently replaced the stock rear drum brakes in my 88 sr5 to the 89 gts rear discs and shocks. I had to replace the brake booster and master cylinder as well just to make sure that the there wasn't a difference between the two different master cylinder's. I bled the lines very well, but my pedal still feels a little spongy. It's not real bad, but it is more spongy then it used to be. I also noticed that the discs in the front are a little bigger than the discs in the rear, so the ones in the front getter hotter than the ones in the rear do. My question is does anyone know why I could be experiencing the spongy problem. Maybe someone else has done a similar modification and could let me know what they encountered.

[Flashmn]

I also noticed that the discs in the front are a little bigger than the discs in the rear, so the ones in the front getter hotter than the ones in the rear do

its not the size, the brakes are front biased. It does sound like you have air in there, when you got the brakes, did you ovehaul the calipers? are they leaking fluid?

[drozy88d]

The calipers are good, no leaks. I was just making sure that I didn't have to switch brake lines as well. I didn't know if maybe the lines in the rear were a little bigger. But I will try to re bleed the brakes. Thanks.

[2wickedtoyz]

did you change the proportioning valve aswell?

[drozy88d]

If the the proportioning valve is inside the clutch master cylinder, then I would say that I replaced it because just to be safe I switched the master cylinder from the 89 gts into my car. Otherwise, I am not sure where that it is, please let me know. Thanks.

[2wickedtoyz]

the proportioning valve is actually on the fire wall . all the brake lines go into it before they go to the rear or the car

[drozy88d]

Yes, I see it. I will change that this weekend to see if that makes a difference. Thanks man.