Quote:
Originally Posted by z71se
Has anyone actually done empirically accurate 60-0 and 100-0 testing before/after the NBS master cylinder swap? Because when I did the swap on my '99 Tahoe, extensive testing with my G-Force meter showed that braking distances actually got WORSE. Needless to say, I went back to the original master.
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With your "empirically" accurate leg pressure?
Did you ever do the "automatic bleed" procedure?
A drum system uses significantly less pressure then a disc system. Not sure if I even believe that changing the rear drum system to the pressure of a disc system would have a negative effect. Maybe the front system pressure goes down after the swap. Doesn't concern me.
Be that as it may, I rebuked this post a long time ago stating many people would gain the better feel/quality of the system by simply getting the automatic bleed done. I didn't think the ABS would have an effect on the normal feel of the brakes since under normal use, the ABS is not engaged. However after reading dozens of stories concerning the results of the automatic bleed, and after having it done it myself. I know it does have an effect.
Incidentally after having thought about this for years I have come to the conclusion that the ABS, although passive, is a restriction on the normal system. Allow me to elaborate. My son has a 1984 Sierra that obviously has NO ABS. His master cylinder is the same one that came on my GMT400 from the factory. He has tremendous pedal feel and incredible stopping power that I can't even get used to after having driven mine. And yet ours is always less than great. Even in the best of situations. Even after the automatic bleed, it's not as hard at braking as other vehicles including the Sierra.
There were 2 things I was going to do to prove this is the case (don't really give a crap currently). One thing was to measure the fluid pressure at all 4 corners of both mine and the Sierra. The second thing was to make a set of jumper tubing to go around the ABS unit in my vehicle to copy his system so to speak without ABS interfering with the hydraulic lines.
If I ever G A C in the future, I might try it. In the mean time, before anyone does any hardware changes, get an automatic bleed.
Can we now let this post die a dignified death?