BUILD THREAD 87 Cutlass EFI build: 5/29/21-CRUISING

Streetbu

Know it all, that doesn't
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May 22, 2011
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Central NY
Ok, let's start over since you don't believe me. Screw the fittings.. Which brake LINE is larger? Should be the one going to the rear of the master cylinder which in turn goes to the front brakes.
 

Injectedcutty

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Nov 24, 2014
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Louisville, KY
Ok, let's start over since you don't believe me. Screw the fittings.. Which brake LINE is larger? Should be the one going to the rear of the master cylinder which in turn goes to the front brakes.
Wellllllll.....I had issues with the stainless lines that go from master down to valve, so I'm using adapters and braided brake lines. On my master, the rear fitting is the larger of the two and I have it going to the rear already.
 

Injectedcutty

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I just got back from ripping around a bit to see how the brakes feel from swapping vacuum sources only. I want to isolate the issue if possible instead of changing multiple things at once.
Tbh, the brakes feel better with the intake vacuum source than they did using the pump! I did some panic stops and such and it felt good. I looped onto the highway around the corner and quickly got to 70. I didn't hear the roar like I have been hearing. It rides a bit rough, but there is alot of poly on this car and everything is still basically new.
I'll consider it a win for today, and keep eyes/ears on it moving forward.
 

565bbchevy

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Aug 8, 2011
8,337
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the brakes feel better with the intake vacuum source than they did using the pump!
Does your pump store reserve vacuum in a canister, if I remember correctly yours was in the trunk with just an on/off switch and not set up to sense vacuum from a source
 

Injectedcutty

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Does your pump store reserve vacuum in a canister, if I remember correctly yours was in the trunk with just an on/off switch and not set up to sense vacuum from a source
No. It was setup the way the instructions said. The hose went straight to the booster, but it did sense vacuum loss as it would build to stay at 22" of vacuum.
 
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Injectedcutty

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Also to note, I just went and checked the setup on the stock master and it's as depicted by Mike earlier. The larger fitting is on the front which goes to rear, smaller on rear closest to booster which powers front. I'm sure I'm overthinking it, just wanting to be sure I don't destroy parts and such.
 

malibudave

Greasemonkey
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Mar 12, 2010
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Houston, TX
Most stock type master cylinders have the rear port going to the front brakes.

If you don't have a hard pedal, you booster is holding vacuum.

Even though the booster may be holding a vacuum, that doesn't mean that it is not the cause of you having to pull the pedal back up with your foot.

Some aftermarket master cylinders can have the rear port going to the front brakes. I believe that Wilwood does this.

Smaller boosters produce less assist.

Larger boosters produce more assist.
 

Injectedcutty

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Nov 24, 2014
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After seeing Donovan post about waxing Olds Cool it dawned on me I've yet to wax my car since being painted, doh! So I checked with the expert and went to get a Mother's clay bar kit and some wax.
No joke, the detail spray that came with the clay bar smells like hot tamales and dang near had my eyes watering lol! Anyways, I went full Daniel son and clay bar'd and waxed the car tonight. It's nice and smooth now, and the wax definitely helped with the clarity some! Be nice to see it outdoors if the weather will cooperate.
That's it for now, here are a few pics as usual...
20210507_204040.jpg
20210508_004935.jpg
20210508_004912.jpg
20210508_004840.jpg
 

Texas82GP

Just-a-worm
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Apr 3, 2015
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Spring, Texas
What ever became of the master cylinder brake line issue?
 

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