I had a similar, spongy/soft/low-pedal, brake problem on a '54corvette race car converted to disc brakes. It tuned out to be the standard (NAPA) flexible brake lines which were not capable of handling the excess pressure of the disc brake system. They were expanding/inflating causing a variable soft pedal much like the effect of air in the lines. We bleed the brakes repeatedly with no avail, until one day I observed while the mechanic was doing the bleeding that the flex lines were moving. We found some high pressure ones and all problems went away..... J D Jung Retromobilia.net ----- Original Message ----- From: "David Schwandt" <finsruskw@xxxxxxxxxxxxxxx> To: "Paul Martin" <paul_martin78ca@xxxxxxxx>, "Ray Jones" <hurst300@xxxxxxxxxx> Cc: chrysler300@xxxxxxxxxxxxxxx Sent: Monday, May 21, 2012 4:48:45 AM Subject: RE: [Chrysler300] Brake problems Could vacuum leaks have anything to do with all the problems folks seem to have w/disc brake conversions?? Sure seems to me that this topic is cropping up very often on this forum as well as the FL forum. One would think by now the process of converting to front discs would be pretty much SOP w/good results and performance. I have considered the switch, but have been putting it off because of all the problems people seem to be having with them. I have never been 100% happy with the stock brakes on my F, but I suspect vacuum leaks may be playing a part here. Jim McGowan has my carbs at present for a complete rehab and I am hoping tightened up throttle shafts will improve Braking by upping the vacuum. Or.....am I just wishfull thinking here?? Dave Schwandt -----Original Message----- From: Chrysler300@xxxxxxxxxxxxxxx [mailto: Chrysler300@xxxxxxxxxxxxxxx ] On Behalf Of Paul Martin Sent: Sunday, May 20, 2012 10:36 PM To: Ray Jones Cc: chrysler300@xxxxxxxxxxxxxxx Subject: Re: [Chrysler300] Brake problems Niels Just completing an AAJ install on my 300F and have experienced similar issues with brake pedal travel. Followed adjustment procedure recommended by members here. I have got some improvement but am still experimenting to get proper pedal height. I think we are experiencing typical spongy brake pedal with disc brakes. Paul [Non-text portions of this message have been removed] ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to http://autos.groups.yahoo.com/group/Chrysler300/join and select the "Leave Group" button For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylangYahoo ! Groups Links [Non-text portions of this message have been removed] ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx To unsubscribe from this group, send an email to bob@xxxxxxxxxxxxx or go to http://autos.groups.yahoo.com/group/Chrysler300/join and select the "Leave Group" button For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/search.htm#querylangYahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: Chrysler300-digest@xxxxxxxxxxxxxxx Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/