R33 Gtst With Gtr Brakes Pedal Feel Issue

[S13q's]

Okay so I have a 180sx which had R33 GTST brake gear on it (drum handbrake and all) and last year I decided to upgrade to GTST calipers to Brembo's from an R33 GTR.

Whilst I was at it I installed a BM57, new DOT 5.1 fluid, new pads, new DBA4000 rotors, new ADR approved braided lines etc.

Now the issue is that when the brake pedal is pushed upon the first push it is soft, then the second, is hard like it should be. The car still brakes by all means but its as if it has 50% of play.

Me and my mechanic bled the system 5 times and it still did the same thing, he had installed these brakes a couple times before and told me he's never had this issue. Thinking its vac related we did a smoke test but nothing came out.

But speaking of vac, when I give the car a hit and let off the accelerator or brake suddenly the revs drop rapidly and at times the car will stall. I just thought it was due to a lack of a BOV but I thought I would mention it if it's related to this.

Recently I have been driving my car pretty hard and I really would like the problem fixed, I just don't know where to start. Any tests I can do would be appreciated.

Here are the possible culprits I've been told it maybe:

- Faulty booster

- Play in the pads

- Air trapped somewhere it cant get out like the ABS unit

[Dose Pipe Sutututu]

I would try bleed the ABS lines first, go around the block and safely try and kick the ABS then head back for a rebleed of the unit followed by bleeding your brakes again

[jiffo]

A long shot but you didn't mount the callipers wrong side for side. (bleeder would be upside down).

Apart from that like John said, bleed the ABS unit again, does sound like air in the system.

[KiwiRS4T]

Did you get a booster with the BM57? If you have a spare try changing the booster. Did you drain the old fluid or push it out with the new? As above - bleed some more.