newr style master cylinder in c3
11-21-2009, 07:57 PM
#1
Le Mans Master
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newr style master cylinder in c3
Is there a cheap and easy way to get rid of the big cast iron master cylinder on my 1980 'vette, and replace it with a newer plasic one? I'm talking about just the fluid reservoir here.
Scott
Scott
11-21-2009, 09:27 PM
#2
Race Director
Not cheap but I just bought this one from Wilwood 
http://www.jegs.com/i/Wilwood/950/260-8556-P/10002/-1
http://www.jegs.com/i/Wilwood/950/260-8556-P/10002/-1
11-21-2009, 09:51 PM
#3
Team Owner
I have had a Pirate Jack Racing m/cyl on my car for some ~5 years now....not a problem....it's aluminum...screw on top....
they have a site....
other guys say a C5 m/cyl works fine too....
they have a site....
other guys say a C5 m/cyl works fine too....
11-21-2009, 11:09 PM
#6
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It's much easier on the '77 and later models due to the difference in the booster design. The m/c bolts right up, fortunately. The big problem is the brake line fittings. They are obviously metric, and our brake junction blocks are SAE. You either need to have custom lines made, or do some flairing yourself. The big problem, as I mentioned, is that one of the line nuts is a very common thread (12mm-1.xx), and the other is an ultra rare 12mm-1zz size. (I can't remember the exact thread sizes. I can find out for you if you go that route.) Because I couldn't find the rare size locally, I got the m/c lines off of a wrecked C5, and reused the hard-to-find flare nut on a new metric line that I cut to length and flared correctly for my appliction.
The m/c is incredibly light (7 lbs lighter than the original), and the aluminum construction doesn't rust or have any paint/brakefluid compatibility issues like the C3 m/c. The C5 m/c piston/bore size is 1 inch.
11-23-2009, 01:12 AM
#7
Le Mans Master
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So, the c5 master cylinder just bolts right up, pretty as you please, but then you have to deal with the brake lines? I don't know much about flaring, could ya cut the flare off of the existing brake lines, and then slip a new metric bolt over the line, then reflare it? Or do you need the new lines, and then deal with conecting them to the old junction block by cutting, slipping the old bolts over, and reflaring the line? Or does it matter, as long as you wind up with a brake line with a new metric size bolt on the m/c end, and an old english one at the junction block end? Oh, wait, I just re-read your post, do you mean that the 2 bolts attaching the brake lines to the c5 m/c are 2 different sizes?
Scott
Scott
Last edited by scottyp99; 11-23-2009 at 01:15 AM.
11-23-2009, 01:46 AM
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Not cheap but I just bought this one from Wilwood
http://www.jegs.com/i/Wilwood/950/260-8556-P/10002/-1
http://www.jegs.com/i/Wilwood/950/260-8556-P/10002/-1
I believe this is one of those (few) parts I've left behind while lightening my Vette....
11-23-2009, 02:34 PM
#9
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So, the c5 master cylinder just bolts right up, pretty as you please, but then you have to deal with the brake lines? I don't know much about flaring, could ya cut the flare off of the existing brake lines, and then slip a new metric bolt over the line, then reflare it? Or do you need the new lines, and then deal with conecting them to the old junction block by cutting, slipping the old bolts over, and reflaring the line? Or does it matter, as long as you wind up with a brake line with a new metric size bolt on the m/c end, and an old english one at the junction block end? Oh, wait, I just re-read your post, do you mean that the 2 bolts attaching the brake lines to the c5 m/c are 2 different sizes?
Scott
Scott
If you're not comfortable doing brake lines, there are a couple specialty companies that make custom brake lines and hoses. Just give them the dimensions, flare type, and flare nut sizes (along with your credit card number, of course), and they'll make up a pair of lines for you.
11-23-2009, 04:15 PM
#10
Melting Slicks
I used a C5 master and had custom lines made locally since I can't make metric bubble flares to save my life.
I got my fittings from either "inline tube" or "classic tube" can't remember which one.
The front brakes attach to the rear port and the rear to the front. This is backwards from the C3, but the lines have to be tweeked to fit anyway. The front brake line uses a 12x1.5mm ISO bubble flare on a 1/4" line. The rear uses a 12x1mm bubble flare on a 1/4" line. The only fittings I could find were for 1/4" line so I have 1/4" for both front and rear then an adapter to drop it down to the 3/16" on one of them to match up to the stock lines.
And both feed to the stock distribution block.
I got my fittings from either "inline tube" or "classic tube" can't remember which one.
The front brakes attach to the rear port and the rear to the front. This is backwards from the C3, but the lines have to be tweeked to fit anyway. The front brake line uses a 12x1.5mm ISO bubble flare on a 1/4" line. The rear uses a 12x1mm bubble flare on a 1/4" line. The only fittings I could find were for 1/4" line so I have 1/4" for both front and rear then an adapter to drop it down to the 3/16" on one of them to match up to the stock lines.
And both feed to the stock distribution block.
11-23-2009, 06:33 PM
#11
Le Mans Master
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I used a C5 master and had custom lines made locally since I can't make metric bubble flares to save my life.
I got my fittings from either "inline tube" or "classic tube" can't remember which one.
The front brakes attach to the rear port and the rear to the front. This is backwards from the C3, but the lines have to be tweeked to fit anyway. The front brake line uses a 12x1.5mm ISO bubble flare on a 1/4" line. The rear uses a 12x1mm bubble flare on a 1/4" line. The only fittings I could find were for 1/4" line so I have 1/4" for both front and rear then an adapter to drop it down to the 3/16" on one of them to match up to the stock lines.
And both feed to the stock distribution block.
I got my fittings from either "inline tube" or "classic tube" can't remember which one.
The front brakes attach to the rear port and the rear to the front. This is backwards from the C3, but the lines have to be tweeked to fit anyway. The front brake line uses a 12x1.5mm ISO bubble flare on a 1/4" line. The rear uses a 12x1mm bubble flare on a 1/4" line. The only fittings I could find were for 1/4" line so I have 1/4" for both front and rear then an adapter to drop it down to the 3/16" on one of them to match up to the stock lines.
And both feed to the stock distribution block.
Is this for real? It looks like the brake lines just pump back into the reservoir! That's crazy!
It has to be some kind of joke. Scott
11-23-2009, 06:40 PM
#12
Melting Slicks
That picture was taken when I "bench" bled the master cylinder. Its easier to bench bleed it on the car than on a bench with a screwdriver. You just push the brake pedal until no more bubbles come through the lines.
11-23-2009, 11:41 PM
#15
11-24-2009, 12:03 AM
#16
Le Mans Master
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Ya know, it's one of those things that I would never think of in a million years, but then someone shows it to ya, and ya think "Why didn't I ever think of that......"
I think you may be right, I do need to get out more....
Scott
11-24-2009, 03:21 PM
#18
Race Director
I can't say 100% for sure it will work no problems but it is supposed to be the correct one for a C3 and I am proceeding not expecting any problems.....as soon as a learn how to make a double flare but you don't need to do this if your lines are OK
11-24-2009, 11:49 PM
#19
I haven't put it on yet but the lines line up and the thread sizes are correct when I tested fitted it.
I can't say 100% for sure it will work no problems but it is supposed to be the correct one for a C3 and I am proceeding not expecting any problems.....as soon as a learn how to make a double flare but you don't need to do this if your lines are OK
I can't say 100% for sure it will work no problems but it is supposed to be the correct one for a C3 and I am proceeding not expecting any problems.....as soon as a learn how to make a double flare but you don't need to do this if your lines are OK
11-25-2009, 12:03 AM
#20
Race Director