#1  
Old 02-26-2021, 08:26 AM
ponchorob ponchorob is offline
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Default pushrod mastercylinder gap

so have problem....in every explaination they say the pushrod from the booster to the master cylinder should have no preload and at least a gap of 0.020...
so have a new right stuff ac delco moraine booster mastercylinder combo for my 68 disc brake firebird ..i also bought the expensive bear brake measuring tool to check the gap...the combo has a massive preload on the combo you even feel it by putting the master cylinder on the booster the booster rod is not adjustable..so i turned off a good amount of master cylinderadapter to get the right gap.... but now to pedal is so near to floor tooks a lot of travel to activate the brakes....friend has the same problem...he installed it with preload so what is going on here...????? Check on my other car also preload !!!!!
Seems that all BOOSTER COMBOS HAVE A LOT OF PRELOAD:... but it shouldnt be there...??????

  #2  
Old 02-26-2021, 10:56 AM
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David Jones David Jones is offline
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So, if you stuck a couple of washers between the master and the booster, you could achieve the right preload? Not sure I'm understanding.

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Old 02-26-2021, 11:35 AM
ponchorob ponchorob is offline
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Have no Problem to correct the right clearence..its seems if i not preload it otherwise ill have much travel in the pedal......but everybody also the professionals tells there should be no preload in no circumstances otherwise ill have severe brake drag....

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Old 02-26-2021, 11:37 AM
Chief of the 60's Chief of the 60's is offline
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Everyone around these parts calls "Right Stuff"..... "Wrong Stuff"

I remember dealing with them on a brake line once. The one they sold me wasn't even close to being bent correctly. I pulled the original line off the car, laid it next to their line and sent them a photo of all the bends that were incorrect. They told me that they copied a line off of a 20,000 mile car and that my original was "wrong". I asked, "Then why doesn't your line follow the frame like every other car built?" Their only answer was, "Well, we sell a lot of them".

I contacted Inline Tube and in a few days had the correct line that followed all the factory clips in the frame and bolted right in as it should.


Last edited by Chief of the 60's; 02-26-2021 at 11:57 AM.
  #5  
Old 02-26-2021, 04:01 PM
JC455 JC455 is offline
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What year is the M/C? If you're using a pre-81 M/C on an 81- up booster (or vice versa), you're going to have fitment issues.
The amount the pushrod-to-M/C sticks out is different between the pre and post 81 designs.

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Old 02-26-2021, 04:16 PM
ponchorob ponchorob is offline
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Interesting............I ordered a complete master booster combo direkt from summit for a 68 firebird.....

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Old 04-10-2021, 01:49 PM
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NeighborsComplaint NeighborsComplaint is offline
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Most aftermarket boosters come with 2 different length pushrods. If using a more modern (Corvette) master, you need the long pushrod. If the master is original style, then the shorter one is correct.

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