RE: [Chrysler300] Magnum Force disc brake conversion
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RE: [Chrysler300] Magnum Force disc brake conversion

There is a Miller tool you are supposed to use to get the pin centered
I believe I have one somewhere.
I had to have a D/S built for Newport Conv we did years ago and the shop in
Dubuque cut the original joints and welded them
In to a new tube. I think I had a length problem is why I needed a new tube
It had no problems whatsoever when done.

-----Original Message-----
From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On
Behalf Of 'John Grady' jkg@xxxxxxxxxxxxxxxxx [Chrysler300]
Sent: Monday, February 22, 2016 2:27 PM
To: 'David Schwandt'; dverity@xxxxxxxxxxx; 'Jean-Yves Chouinard';
Chrysler300@xxxxxxxxxxxxxxx; 'Andy Mikonis'; 'Jamie Hyde'
Subject: RE: [Chrysler300] Magnum Force disc brake conversion

Well, Dave, ----on those joints , they are right! Housing often gets an
outward  "dent", or loose place, from repetitive rubbing in one place , or
Banzai launch, shaft vibrates. About 60-70 mph. No real cure, except all
new, but then try to center that pin and shim it just right? 1930 design.
Careful rebuild , dent still there,  so is the vibration, but mileage
dependent . If driven like a silver toyota, no problems. Must have design
origins way back in patent squabbles over the spicer joint. They knew that
torque problem, --- there are two sizes , so small early MOPAR one was not
going to cut it on later 300. 


We need the nice 1350.


Got a cure for that too. But long email for here . 


I have learned over many years to listen, but then see if it really makes
any sense. The noise about two leading shoe  brakes has been loud and
constant since new. Despite from a pure engineering perspective,  a much
better technical design..if it works?  Worked great for me when new, I was
there, 2-3 cars.. And non power brakes.


Sort of irrefutable fact, not just "opinion" that C300, 300B cleaned
everybody's clock with those brakes. NASCAR racing is brutal on brakes ,
every aspect of them--- let alone an almost 5000 lb car. So it is NOT the
brakes.given that knowledge.   So someone who cannot get them to work blames
the brakes ?? Problem ,of course, cannot ever ever be between the ears of
very adamant,  loud,  critical and opinionated speaker.


To go even further, 100%  at my own risk, as an engineer, --the ability to
store heat short term (a minute or so, before air cooling )  is proportional
(only ) to the metal weight you can sink it in to.=temp rise you get.  .
Those 12 " drums are ? same or more lbs than 11" discs. ? a solid disk
CANNOT cool as fast as a big  drum,  as cooling is by surface area exposed
to air , drum wins that too , up to a point . But cooling rate also related
to temperature, and extremely hot disc will cool (throw off heat) fast.
Vented discs with fan scroll in between surfaces ,may be better--- over 15
minutes interval or so of cooling , if moving.. 


But look at those  Buick 12x3" finned aluminum drums used in later racing
with these drum brakes.( and stock on Buicks 60-62 or so)  Looks to me to
have ~ 2 X the radiating area to air of any reasonable disc brake.  What if
these are better than discs-for first 2-3 hard stops? ? And then fins throw
off more average watts than  a disc? But drum distorts when hot, bad, so can
get to mimic fade,  as it may go bell mouth shape. But not real fade
,although same end point to driver ? Maybe Buicks do not? Discs can run
almost glowing hot and work, why hi temp fluid etc. Better pads etc . But
inherently better?  even for racing ? Caliper gets too hot = you are done
for, suddenly no brakes, boiling fluid,.. Drums will catch fire first ,
wheel cylinders are  back from friction materials. "Discs are
better"---seems to be in question, especially was in 62-65  or so. .   300B
did not have the benefit of Buick drums back in the day. Did ok anyway. So
better than Carl had readily available.


Last, my brand new 82 Dodge truck with discs burned them all up to nothing,
as in locked solid by boiling fluid,  carrying full load of wood 40 miles in
traffic. Drums never did that. Nor did Chevy 70's-80's trucks more to the
point. ( nice brakes) . Dodge truck brakes were awful in that period. Discs
looked like toys. JEEPS too, same thing,  burning up discs , my 97 and 02
both did that. 


While on Nascar,  I read somewhere way back that the Mercury outboard 300's
ran imperial wheels , to get 5 or 5.5 bolt patterns ,because the 4.5 "
pattern loads would fatigue the wheel disc  enough with high speed corner
loads to have the center come out. (!!!) Not sure if 55  or 56 Imperial
limos or something (??)  might have had even bigger brakes that the 12" on
300. And whether the Nascar 300's used them. Carl went after everything, he
must have gone after brakes #1. Any one know about that? A really thorough
technical analysis of what he did and learned on those cars would be
extremely valuable today. I wonder how wide those wheels were? If you look
at that pix of Vicki and 300B, that car has seriously wide rims. 


Loved that clip of 300 B racing a few weeks back..and doing just fine with
these "awful brakes" ---and that maybe U joint too! 


You got me going..!


From: David Schwandt [mailto:finsruskw@xxxxxxxxxxxxxxx]
Sent: Monday, February 22, 2016 10:00 AM
To: 'John Grady'; dverity@xxxxxxxxxxx; 'Jean-Yves Chouinard';
Chrysler300@xxxxxxxxxxxxxxx; 'Andy Mikonis'
Subject: RE: [Chrysler300] Magnum Force disc brake conversion


Brake system doom and gloom is all I hear on the Forward look site as well,
how bad they are and should be pitched and replaced

Same story w/the ball and trunnion U-joints that were used for how many
years on MoPars?


From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On
Behalf Of 'John Grady' jkg@xxxxxxxxxxxxxxxxx [Chrysler300]
Sent: Monday, February 22, 2016 8:57 AM
To: dverity@xxxxxxxxxxx; 'Jean-Yves Chouinard'; Chrysler300@xxxxxxxxxxxxxxx;
'Andy Mikonis'
Subject: RE: [Chrysler300] Magnum Force disc brake conversion


With you 100% Don..


From: Chrysler300@xxxxxxxxxxxxxxx [mailto:Chrysler300@xxxxxxxxxxxxxxx] On
Behalf Of dverity@xxxxxxxxxxx [Chrysler300]
Sent: Thursday, February 18, 2016 7:38 PM
To: Jean-Yves Chouinard; Chrysler300@xxxxxxxxxxxxxxx; Andy Mikonis
Subject: Re: [Chrysler300] Magnum Force disc brake conversion



I think the 12 inch brakes were a heavy duty option on the Dodge and


I have never had issues with the original drum brakes that I haven't been
able to fix. Linings separating from the shoes, and stretched springs come
to mind. I always do new master and wheel cylinders, and don't turn the
drums unless they need it. If there are hard spots on the drums, you can't
remove them with a regular brake lathe. An old time shop that used to be in
this area had a grinder attachment that could be used on their lathe to take
care of hard spots. They also arc grinded shoes for many of my cars. I have
my own arc grinding machine now thanks to the late great John H.


I have had issues with disc brake conversions, and dual masters though. The
pedal ends up being way to low for comfort, and the stopping power is not
that much better. The plumbing is a pain too. Chrysler designed them well in
the first place. 




From: mailto:Chrysler300-noreply@xxxxxxxxxxxxxxx 

Sent: Thursday, February 18, 2016 6:36 PM

To: Chrysler300@xxxxxxxxxxxxxxx ; Andy Mikonis <mailto:r41hp@xxxxxxxxx>  

Subject: Re: [Chrysler300] Magnum Force disc brake conversion



Very interesting info Andy, thank you for sharing.

Surprising that a 2100 pound Daimler with disc brakes took 33 feet more to
stop!! Chrysler brakes were not that bad!! Dart a few hundred pounds less
than the G, explains the 125 feet for the Dart, which probably was equipped
with 11 inch brakes ...vs 12 inch for G.





From: Chrysler300@xxxxxxxxxxxxxxx <Chrysler300@xxxxxxxxxxxxxxx> on behalf of
Andy Mikonis r41hp@xxxxxxxxx [Chrysler300]
Sent: February 18, 2016 5:11 PM
To: chrysler300@xxxxxxxxxxxxxxx
Subject: Re: [Chrysler300] Magnum Force disc brake conversion 



Yes, John, I agree. One of my mechanic mentors who opened a service station
in 1957 always told me the problem with these brakes was with the mechanics
and not the engineers.


He always arc ground. (In fact, I have his arc grinder now.) The linings he
ground for me in 1990 are still on my G after 100K+ miles.


Other things I have published in the club newsletter the newbies wouldn't
have seen:


Paul Mallwitz, a Chrysler engineer who spoke at a club meet in 1982 was
asked: "How did you get the brakes to work on these cars?"


Reply: "With great difficulty. Those Center Plane brakes had to be put
together like a watch in order to make them work properly."

Next, in the April 1961 issue Motor Life magazine tested a 300-G and
recorded a 60 to 0 of 131 feet. That's average for today's cars. Mistake?
Don't think so. Dart D-500 in the same issue: 125 feet!


Other cars in the same issue:

Olds Super 88: 159 ft.

Olds F-85: 171 ft.

Daimler SP-250: 194 ft. (2090 lbs. with disc brakes)



300 editor

In a swiftly warming Chicago

On Feb 17, 2016, at 1:18 PM, 'John Grady' jkg@xxxxxxxxxxxxxxxxx
[Chrysler300] <Chrysler300-noreply@xxxxxxxxxxxxxxx> wrote:


Just a FYI< 


A lot of the fitment differences for a total upgrade are because they
changed at various times the lower (at least) ball joint OD , how it fits,
(press or screw in to lower arm) and the size of that ball joint taper that
goes into the steering knuckle. I know it was long ago, details not 100%
clear tonight , , but I put 67-68 Dodge police car package steering
knuckles, discs  and ball joints into 57 Dodge control arm by reinforcing
the end of lower control arm with added ring of 1/4" steel and then boring
that out for what I think was the larger (than 57) 67-68 lower ball joint. I
think top 57 one fit the knuckle or spindle ok, or found one that fit. .
That let us put on stock 67 or 68 police car disc brakes, the "big discs"--
hot set up long ago --before disc kits--- on 57 Mopar. 


Now they have kits that fit the old knuckle.and leave the small ball joints.
Two kinds of kits?? ..special adapter  knuckle-- or not . By way of
awareness, not comparing. But insight into why some years and not others.


This change to discs on my 57 was made , really, because I had frankly
screwed up more than one total contact brake setup,  through not knowing
what I was doing, after buying all new parts, ,  and was fed up with "all
the problems". They are real problems.   But is it the brakes? 


I had a brand new 60 dodge , in 60, manual brakes , bought then because I
liked  two leading shoes on the manual, had heard and seen many horror
stories about power brakes in general 55-60, --60 Dart was a great set up! I
beat it unmercifully. It was perfect in every way , brake wise; used to
laugh at best friend's GM 57 Pontiac power brakes with on-off feel. Beating
unmercifully,  was street drag racing several nights a week to 100 mph + ,=
going was the problem,  not stopping. No pulling no grabbing..


The basic torsion bar suspension design  is about the same across these
years ; all this by way of info, not advocating doing it, but good to think
or know about. . 


Do you need discs??   Sort of falls out of it? Idiot proof as far as
assembling the pads..


I am in the middle of doing some discs, but still ambivalent. Not if drums
are working right,  is one answer. They worked right at the beginning. 


Also looking back, many of the problems with total contact , or other
Chrysler brakes are errors caused by experts (who are not) in putting them
together right, especially arcing the new shoes to a turned drum. If you do
not, with all new parts, the brakes do not work. Discs get into front/rear
balance, another possible can of worms, despite that  balance "valve" . They
have inherently different actions..


They won all those NASCAR races with them, stories about "fade" on the
street leave me cold. Worse than fade--- -------if the shoes are not
touching the drum , most of the way around! 


Sure ,  not as good as modern discs, but awfully good brakes. 


Did you know GM put MOPAR total contact brakes on the racing Corvettes with
Buick drums about 1960??  they watched the 300B race,  brakes and all, and
win . . So would I. On a light corvette? Bulletproof . And the "fading after
3 panic stops from 120+ mph"  in contemporary 300 tests  is not exactly how
we use our cars today. What reminded me of all that , was seeing that 300B
race clip a few weeks back , on this site . No disc conversions , yet racing
competitively for real, in 2015? Braking hard on corners over and over...
(he did have Buick drums too..which have aluminum fins on them.  60 to maybe
62. That forces a wheel change too ). Before discs, that was the hot setup.
Rods, Bonneville etc . The brakes we take off. 


My problems with these brakes on 300F over the years was not fade..they were
pulling, grabbing, low pedal , poor stopping rate, squealing  etc etc . 300
B or 60 Dart was not like that ..  Why?


Just sayin..there is a disconnect here somewhere. Others see it? 




From:  <mailto:Chrysler300@xxxxxxxxxxxxxxx> Chrysler300@xxxxxxxxxxxxxxx [
<mailto:Chrysler300@xxxxxxxxxxxxxxx> mailto:Chrysler300@xxxxxxxxxxxxxxx] On
Behalf Of 'Bob Jasinski'  <mailto:rpjasin@xxxxxxxxxxx> rpjasin@xxxxxxxxxxx
Sent: Wednesday, February 17, 2016 4:46 PM
To: 'John Nowosacki'
Cc: 'Chrysler 300 List'
Subject: RE: [Chrysler300] Magnum Force disc brake conversion



I sent them an email.  I'll report back with what they send me.



Bob J


From: John Nowosacki [ <mailto:jsnowosacki@xxxxxxxxx>
Sent: Wednesday, February 17, 2016 1:22 PM
To: Bob Jasinski
Cc: Chrysler 300 List
Subject: Re: [Chrysler300] Magnum Force disc brake conversion


pictures say 57 to 61, but when I click on the link for picture or part
number, it says 65 to 72?


On Wed, Feb 17, 2016 at 3:42 PM, 'Bob Jasinski'
<mailto:rpjasin@xxxxxxxxxxx> rpjasin@xxxxxxxxxxx [Chrysler300] <
Chrysler300-noreply@xxxxxxxxxxxxxxx> wrote:

Has anyone  looked into or installed the disc brake conversion kit offered
by Magnum Force?




They offer several kits and appear to be fairly new offerings.  


Bob J







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Posted by: "John Grady" <jkg@xxxxxxxxxxxxxxxxx>

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Posted by: "David Schwandt" <finsruskw@xxxxxxxxxxxxxxx>

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