i have a problem with my brakes on my 1200 ute i have done the ca18 silvia convertion im now running the twin resivour master cylinder and still the standard rear brake cylinders what is happening is th front brakes are staying on and they are dragging does any on know how to fix this

What master cylinder? Are you using the correct distribution block? Does the front line go into the front or rear of the master?

Are you using a master cylinder that is intended for a drum brake car, on a car with discs?
If so, then simply remove the 'residual pressure check valve' form the front brake portion of the cylinder. Check the appropriate service manal for this. [or get help from someone who knows what they're doing]

Other poossibilities.
Piston in caliper is sticking
Master cylinder push rod does not have free play at back of piston when pedal fully up.