my buddy has a 97 tj sahara. he just bought a 8.8 from ecgs and installed it. he also bought new front calipers for the hp30 he swapped in. had a hard time getting brakes to bleed, but ran quite a bit of fluid through lines. The pedal is hard, very hard. you cant even stand on it to make it stop. the booster is hooked up properly. when you unplug the booster, the pedal would not be as hard and you could actually push it. my question for you guys is do you think it would be master cylinder or booster?
thanks for replies

sounds like it is the booster to me
but at the parts house you can get both as an assbley for around the same price
i would get both

Have your friend check to be sure his calipers are not upside down. The bleeders should be positioned up high, not down low. If they are upside down the bleeders will be too low to draw out air and the brakes will not bleed correctly.

Basically look and see if the bleeder would be positioned higher up if the caliper were to be flipped. This is a common mistake and an easy fix if this is the case.

he did make that mistake first but i told him and he flipped them so bleeders are at highest point now.

Upside down calipers wouldn't make the pedal impossible to push.

Did he mess with the booster or master during this process?

didn't mess with the master cylinder or the booster during the process

It doesn't make sense, but it could just be a coincidence that the booster went bad, although that's very bizarre that you can't push it with both feet and nothing was touched.

Is this with the motor on or off and is the vacuum line hooked up?

vacuum line is hooked up.
when it is running, the pedal is hard.
if you take the vacuum line off when it is running, he says you can push the pedal with your feet.

edit: he also mentioned it sat overnight with rear bleeders open..
possible airlock???

or would the check valve in the booster be causing this? im lost here