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Big Ur-q Brake swap
Here's the scoop on the "big brake upgrade" on my 1983 Ur-q.
After taking the entire lot of parts; new Girling 60 calipers (ala B. Howell),
PBR metal master pads, used 87 5KCStq carriers, new rubber covers,
ATE Super blue racing fluid, Brembo 276mm drilled rotors (ala B. Howell)
and my coupe to Libra Racing for the switch over, I have a driving test to
John Buffum slid this job in right before flying out to the Wild West Rally
in Washington, so they were a little short on time but did it none the less.
John remarked that the pedal "feel" was very different than before they
switched it over (guess he took it for some errands and got a feel for my
stock coupe before working on it...) After the switch over, he remarked
that the pedal goes consiberably down, 1/3 of the way to the floor before
everything starts to work, and they haven't seen anything like this...?
But do they work..!!!
Well, bleeding the brakes twice confirmed that there was no air in the lines.
He did test the brakes, as he does all his rally cars, in his lot and showed me
the long 20 ft plus FRONT tire lock ups and just a trace of rear lock ups.
"Way too much front brake, Thompson, maybe a different proportioning
valve would help this..." he said. Ok, sounds good to me. But I'm still
by the way in which the pedal goes way down, and just trying to get used to
this feel before I've got the monster brakes kicking in.
A quick phone call to Keith Anderson, Ben Howell (and John Buffum called Bruno)
confirmed that when you install this set up, the pedal feel changes to
1/3 of the way" (soft feeling like the master cylinder isn't working) and then -
WHAMO very progressive SUPER brakes, much like the way in which the wifes
86 5KCStq feels right off the top. I do get some very noticable front end dip
when the big ass twin calipers kick in, but the Konis help out here.
It is just wierd to jump on the brakes and feel the pedal go down so far before
everything starts to work. Is this correct or am I just dealing with a itemized
problem with my coupe...? (two other Ur-q's do the same with this set up...)
Does the stock proportioning valve create this pedal feel or is it a function of
the brake booster system compensating for the additional hydraulic fluid that
the twin piston Girling 60 calipers use up before really kicking in...? I will
get to the bottom of this pedal feel thing one way or another, but in the
meantime man do I have some REAL monster brakes. This
set up by far is the single most improvement to my Ur-q coupe.
Ur-q's all go like stink, but stopping them is another story. Compairing
brakes to my experience racing and autocrossing my old 72 911RS replica,
dads 76 Carrera 3.0, and an his 'ol 69 911E Porsche, the Ur-q's biggest
dissapointment is the brakes. This set up puts the Ur-q right up there with
the powerfull brakes of a 911. Just short of the pedal feel and getting the
proportioning of front to rear just right will take some time, and experimenting
with different parts, but again does it STOP.
If anyone else has done this setup and has additional information, please
on how your pedal feels, performance, etc... Keith Anderson say's, "when
I'm at Brainerd
Raceway I can go WAY past the last braking point BEFORE getting on
the brakes, I'm still up on the cam, full throttle when your supposed to
braking for the turns..." Yoweee...!!! can't wait till I take it on the track.
Thompson Smith - New England Region, QCUSA