#$$@& HydroBoost Swap

4 hours into my Hydroboost upgrade on my 1997 2 door.
What's the trick to getting access to the nut and bolt on top of the brake pedal??
Old MC is off, Vaccuum booster off, new MC bench bled and ready to go in, new hydroboost ready to go in......WTF is with this old pedal.

I have column down and can see/capture the nut but can't contort my hand to get the bolt.
Any tricks??

8 PM update; 6 hours in.
Old pedal is out and new one in; That was the toughest part of this whole upgrade. I replaced the offset mounting plate on the HB unit with a centered one and mounted to firewall; MC is on.

Plumbing lines and bleeding brakes in the AM.

Tbruz

you would have demounted the SRS controller and remove the metal bracket it mounts to. once out you can reach in up and forward to feel the bolt. 18mm head I believe. Use extensions as needed to get straight on it. Remove that bolt only. The nut is spot welded on the other side so you don't need to get that one. And that would have been the procedure.

3 additional hours on Saturday and I'm done; hydroboost upgrade is complete.
Initial impressions are that the braking performance is definitively improved; ie shorter distance required to stop.
I am a little disappointed in the pedal though, its not "instantly" firm at its uppermost location as I expected(maybe erroneously expected). It does firm up about a quarter way down and system is capable of locking brakes up with ABS pulsing.

1st cold start on Sunday am had a fairly soft pedal, pumped up fine after about two,three or four pumps; thinking a re-bleed is in my immediate future
Tbruz

Still a little air it sounds like but you are on the right track. Pedal will not firm up like others say the nbs mc does. You have to travel the pedal so far to get the mc pistons to seal and put massive pressure on the brakes. But when it does, OH BABY! My abs is out of order for now. it complains of a motor issue and random vss issue. speedo still work tho. Have a spare vss but the motor issue may appear to be a bad connection or relay in the electronics half. No shops are willing to repair it so I may just grab a jy unit for it computer and disassemble the hydro unit to examine and look at possible parts for rebuild and develop diagnosis steps. or I could buy a new electronics half for $500+. until then I got to be careful to prevent lockup. Had to panic brake once and fishtailed it about 40°.

Thanks for confirming my suspicions Sunlit.
two questions:

1) Does your HB upgrade suffer from a softer pedal at first cold start?

2) Now that we have Hydroboost system installed, Is it true that we cannot use the NBS master cylinder fix to firm the pedal travel due to the size difference in the back of the NNB MC versus the opening on the hydroboost unit?

Thanks
Tbruz

no. try bleeding it again until clean new fluid comes out. Mind you it is very easy to press the pedal it hardly takes any effort. if you press it down hard and far enough you should hear the pump bog the engine slightly. Means pump and booster are working well. yes it needs to be enlarged but unless you put an nbs mc without changing over to some rear disc brake system it just won't be right. the brake balance will be off an will require more effort by you at the same time.

So I finally got around to re-bleeding the brakes.
Pedal got a little bit firmer, slightly higher up as well.
I then borrowed a friends Snap-On Solus Pro and ran the ABS Activation test 4 times as per the factory shop manual. This test cycles the ABS pump and valves in sequence.

Pedal got a LOT better, still not perfect(say 8 out of 10), but the shop manual says to re-bleed again to improve pedal feel.

I love this new hydroboost brake performance.

I'm waiting on some Super blue brake fluid so I can flush the entire system and ensure I have no air bubbles left in any line.
Tbruz

have you smurfed your brake system yet?

Tbruz said:

2) Now that we have Hydroboost system installed, Is it true that we cannot use the NBS master cylinder fix to firm the pedal travel due to the size difference in the back of the NNB MC versus the opening on the hydroboost unit?
Tbruz

Click to expand...

You can only use a nbs master cylinder if you machine out the booster.