Hey guys I know this is not the Ef forum but I need and intelligent answer.

My father and I Autox and track his 88 CRX Si (see avatar). I have noticed lately that the brakes are soft for the first 3rd of the pedal. We have SS lines, new master cylinder, new fluid, new calipers, new rotors, Hawk HPS pad, new rear wheel cylinders, new rear shoes, and new rear drums. After this rebuild I have driven the car for about 70 miles and this has been stop and go street driving and harder 60mph to 25mph slowdowns getting off the local interstate. The pedal is still not linear. We have bled the lines to many times to count so I know its not air in the lines.
Here are my ideas:

The master cylinder has gone bad.

The master cylinder in for a 90-91 (rear disk car)

The brake booster is bad.

The stock brake valve assembly has gone bad or has trash in it for some reason.


Any help would be greatly appreciated.

 

my 89 crx si behaves the same way.....and i swapped in new master, discs, pads, rear shoes, rear drums, and stainless lines all the way around with blue ATE fluid and purge/bleed the lines at least twice a year....it does brake fine though....but all of seems to be in the last bit of pedal travel........bump for the man.......anybody got other ideas?

 

My Civic does the same thing. I adjusted the rear drums and it is more solid now but still real long.

 

Same thing here changed almost everything and bled many times, I am switching to rear disc this week.

 

Could be pad knockback...

Does the peddle stay high and firm right after NEW front pads are installed? If yes, it's probably knockback, and either your rotors are warped OR (more likely) your hubs/wheel bearings need to be replaced.

More on pad knockback: http://www.stoptech.com/tech_i...shtml

Thawley -- who is only one of the several Civic/CRX guys in WCHC who does a little left-foot-pump action before the turn at the end of the straight

 

https://honda-tech.com/zerothread?id=255804
maybe this will help.

-spenc

 

you're using the stock prop valve?

 

ohhhhh....

 

Lo-Buck: We are going to look into that adjustment.
rsca_crx: Yes its the original proportion valve. But it has to be an OEM valve because of the class we run the car in (STS2). Can they go bad?

We are going to replace the brake booster in the next few days. I'll post any findings.

Thanx for the help so far.