Speculation and comments;
I think the reason the KH system was used for only 1955 was for the following reasons:
It was the first year the master cylinder was moved from under the floor to the firewall.
It was the last year that Chrysler used the Lockheed brakes.
I speculate that the KH master was an oddball and only an stop gap for the 1956 system.
Vacuum can have a huge effect on brake systems and I say this from personal experience. When I rebuilt the engine in our 300C I used a cam that was highly recommended and should have looked much closer at the figures attached to it. That is another story that a few of you know but we don't need to go there.
Bottom line is the car was very difficult to stop going forward and you couldn't stop it in reverse. The plus and the ONLY plus to all of this is when you arrived at a show it really had a roll to it and sounded very nasty but if you stood behind the car for a short period you could hardly breath due to exhaust fumes.
I dropped about another $500 and spent the weekend changing out the cam to something very close to the original but with a more modern grind. The car immediately stopped, idled well and had much more power through the entire driving range. Once again I should have known better as with my 54 years of high performance VW engine building I've seen it over and over when builders "over cam" a motor because they think that is the way to go. As my late father (a very wise man) use to tell me in my youth, "The engineers made it that way for a reason". He was right.............
I've had two Letter Cars with AAJ Disc and both worked well on the stock master cylinder but one must remember the rotors and calipers are somewhat small compared to what cars use today. For me they work better than the drums but not a major difference.
From: "'Jack Boyle' jackcboyle@xxxxxxxxx [Chrysler300]" <Chrysler300-noreply@xxxxxxxxxxxxxxx>
Sent: Tuesday, April 4, 2017 1:31 PM
Subject: [Chrysler300] 3rd update: AAJ brake install on C300
First, thanks to Marshall Goodnight for putting a vacuum gage on several
C300 engines. The vacuum from Marshall and others range from 14" to 17",
with 17" marginal but adequate. My car sees 14" - 15" under most conditions.
I wonder if the factory took the cam into account when designing the system?
I also wonder if the K-H system was only used for one year - then to
mitigate a problem we started to see Vacuum canisters on most of our cars.
So, after 120 miles on the pads and considerable research I am down to 3
1. Add a '56 style vacuum canister which may help a little in city driving
but the 14" is still a problem?
2. Add a vacuum pump ($200+). These are marketed specifically for cars
with radical cams. They make noise but are switched on at 17" and run to
keep the vacuum at 21" . See: http://www.getdiscbrakes.com/evp01#
3. Live with the system as is which offers about the same braking ability
as the '55 factory set up but with the safety of dual M/C and no fade.
(913) 544 4650
Enjoying the same C-300 since 1967
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