What causes brakes to drag

[Les_Sr]

I have a 90 LX 2.3, When I bought it I put new calipers (stock) on it and new pads and shoes on all four corners, I have since swaped the master cylinder with a 93 Cobra MC and used Matt Bobbitt's 2-3port conversion kit. Since then the brakes drag on and off, I went out lastnight and the brakes started draging 2 minutes after I left my house and continued untill I got to where I was going. After letting the car sit for a few hours, The brakes did not drag at all the entire way home! It is normal for them to drag for a bit, then stop and not do it for the rest of the day. Any ideas what could cause this? I have flushed the entire brake system and filled it with DOT3. I am guessing the brake booster but I wanted a second opinion before I spent $110 for the cobra Booster! also when the brakes are acting right the pedal is slightly soft (Normal) but when the brakes are draging the pedal gets really hard!

 

[Asha'man]

That seems like a lot of MC for stock 2.3 brakes. Is everything else stock? You should be running that combo with 73mm calipers.

Ash

 

[Les_Sr]

I upgraded the MC so I can install rear disk, but haven't gotten to it yet! could just the larger MC be the problem?

 

[Les_Sr]

bump

 

[Duanetc1]

I am guessing since you have a cobra m/c in there the back brakes drag-Rear caliper take more force to move than brake drums thus the need for a bigger m/c since you dont have rear calipers yet maybe you are overloading the wheel cylinders with too much pressure??? Just a thought, Duane

 

[Les_Sr]

Actualy it is the opposite, The rears are fine at the moment but the front drag! I re-bled the calipers while they were still locked yesterday and white foam came out and the pedal has gotten much softer! but it seams like they are slowly getting tight again.

 

[Dr_EluSivE]

probably too big of a master for the tiny 4 banger brakes.i would throw so dual pistons, or at least a set of GT calipers and brakes on there for using that Mc.

Dr.

 

[Les_Sr]

Are the dual piston a direct bolt-on? I am going to install SN95 spindles, hubs, calipers and rotors in the near future, also the SN95 rear disk. I have all the parts I just have not installed them yet.