i have gsr brakes on my hatch including the rear disc conversion and i heard if you change the d-series brake booster to a b-series (gsr) that it will make you brakes better does anyone know if this is true? and is it worth it?

 

yes.

 

so i should do it if i have a gsr brakebooster

 

Getting a larger master cylinder will improve brake feel. Get a 91 Civic EX sedan (15/16") master cylinder. It will bolt onto the stock Civic brake booster.

 

or 94+ and any teg booster.

 

No. A larger brake booster does not make braking performance better. In fact, it has no effect on the way anything in the braking system operates. A larger booster will simply make the pedal easier to push. This is not necissarily a good thing though. The human body respondes much better to "pressure", rather than position. This means that a person will be able modulate the brake pedal much easier with a good firm pedal instead of a mushy pedal with little feedback.

You would do much better to keep your stock brake booster. And since you've already upgraded to larger than stock front brakes, you will need to also upgrade to a larger master cylinder. The integra front calipers require a 15/16" master cylinder for a non-ABS system. As BlueIntegraBoy already pointed out, the master cylinder found on the 90-91 Civic EX 4dr will bolt directly to both your stock brake booster, and your fluid hard-lines. I believe Fastbrakes sells it for $120 brand new and that is a good deal for the OEM Nissin part.