66 brake upgrade
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Instructor
Joined: Aug 2018
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From: Harrisburg, Pa
66 brake upgrade
Finally time to get rid of my original 66 single master cycle and convert to dual. I’m looking at the kit from ZIP #DB-503 with th 67 style master and appropriate lines and fittings. My thoughts are should I go ahead and ad power booster while I’m at it ?
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Jun 3, 2026, 05:19 PM
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Le Mans Master
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From: Temple Terrace Florida
I added the 67 style dual master and booster when I did a body off on my 66 years ago. I also changed out all the hard and soft lines at that time. I used the 67 hard lines as well. Worked well for me with no surprises. The older I get, the easier I want the car to be to drive. I still like to row the gears the old fashioned way. Jerry
Drifting
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From: Edmonds Washington (Stunning view of Olympic Mtns and Puget Sound)
2024 C2 of the Year Finalist - Unmodified
2023 C2 of the Year Finalist - Unmodified
The factory original brakes are sufficient enough to throw you through windshield on a panic stop. Dual reservoir not necessary IMHO. 
begee22
begee22
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Drifting
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Drifting
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From: Australia
If it makes no difference, why was it an option ?
I’ve added one to two cars I’ve owned and it definitely takes less effort to stop quickly in heavy traffic or when you have little warning.
If you live in a small town and just putter around, you probably won’t ever need it.
I’ve added one to two cars I’ve owned and it definitely takes less effort to stop quickly in heavy traffic or when you have little warning.
If you live in a small town and just putter around, you probably won’t ever need it.
Team Owner
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From: Middle TN by way of KY, OH, VA, IL, CA, FL, NY, SC, HI
I'm planning on redoing the brake system on my '65 single circuit non-power brakes shortly after we move into our new under construction house in which the C2 gets its own garage (it's in storage now 
). I am old school and part of the appeal of my low optioned '65 (but for the L76 engine) is the no power anything on it. However, the few occasions where I have allowed others (family members only) to drive it, the brake effort has been disconcerting to them, so yes, I'm planning on adding a vacuum booster when I do the conversion to dual master cylinder (which I'm doing for safety sake). I have had one caliper seal fail, dumping the brake fluid out, which would be no fun with a single circuit. YMMV.
). I am old school and part of the appeal of my low optioned '65 (but for the L76 engine) is the no power anything on it. However, the few occasions where I have allowed others (family members only) to drive it, the brake effort has been disconcerting to them, so yes, I'm planning on adding a vacuum booster when I do the conversion to dual master cylinder (which I'm doing for safety sake). I have had one caliper seal fail, dumping the brake fluid out, which would be no fun with a single circuit. YMMV.
Le Mans Master
Joined: Feb 2014
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From: Richardson Texas
I'm planning on redoing the brake system on my '65 single circuit non-power brakes shortly after we move into our new under construction house in which the C2 gets its own garage (it's in storage now ). I am old school and part of the appeal of my low optioned '65 (but for the L76 engine) is the no power anything on it. However, the few occasions where I have allowed others (family members only) to drive it, the brake effort has been disconcerting to them, so yes, I'm planning on adding a vacuum booster when I do the conversion to dual master cylinder (which I'm doing for safety sake). I have had one caliper seal fail, dumping the brake fluid out, which would be no fun with a single circuit. YMMV.
). I am old school and part of the appeal of my low optioned '65 (but for the L76 engine) is the no power anything on it. However, the few occasions where I have allowed others (family members only) to drive it, the brake effort has been disconcerting to them, so yes, I'm planning on adding a vacuum booster when I do the conversion to dual master cylinder (which I'm doing for safety sake). I have had one caliper seal fail, dumping the brake fluid out, which would be no fun with a single circuit. YMMV. It only takes one time to get your attention. A little bit of peace of mind (and, additional safety) is always nice in these old cars
Team Owner
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Le Mans Master
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From: Richardson Texas
Leif, you're exactly right! As a result of being an old submariner - which, like aviation - use a checklist for everything, finding the puddle of brake fluid dumped out on the garage floor as I was heading out to give my MIL a ride in my '65 (imagine if I had a wreck with her in the car?) triggered my use of a pre-drive checklist that includes the brake fluid reservoir level check as well as a check for any puddles of liquid on the ground under or around the car.
Drifting
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From: Sacramento, Ca
Concerning the OP's original question about whether or not to add a power booster, I personally highly recommend it.
Ted
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From: Shamong, NJ
Many years ago I drove a 74 I had to the Memorial Day IMSA race at Lime Rock Part CT. In bumper to bumper traffic leaving the race, I blew out a rear caliper seal in Amenia NY. Without a dual reservoir master cylinder I would have surely hit the car in front of me. We managed to drive the 200 miles back home that night with just front brakes, and maybe a little help from the mostly useless OEM parking brakes.
By the way, the 74 had manual brakes and I liked them more than the power brakes in other Corvettes I've had and/or driven. I've just always felt the Corvette's manual brakes had better feel and feedback than the stock power assisted brakes.
By the way, the 74 had manual brakes and I liked them more than the power brakes in other Corvettes I've had and/or driven. I've just always felt the Corvette's manual brakes had better feel and feedback than the stock power assisted brakes.
Team Owner
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