C3 "noob" brake questions
Thread Starter
Racer
Joined: Sep 2006
Posts: 395
Likes: 31
From: Gurnee, IL
St. Jude Donor '12
C3 "noob" brake questions
Guys
I posted up a month ago with my new/old '68 big block purchase. This month I've spent time going over all the issues I have as this surprisingly good runner needs a lot of love and restore work over the next few years.
I have a few early questions (please be kind) as I've restored a C4 with my son in the past and own a fun C6 Z06). I have brake fluid leaking down the firewall "cover" and I know the master cylinder (MC) is original. Safety is always paramount as my wife likes to drive the manuals and these big blocks don't come cheap. PS...Just got my 68 AIMs manual from NCRS (what a great helper)!!!!
Two questions:
(1) If I can't SEE the brake booster in the engine bay attached to the MC, than my car IS manual braking right (i.e. it's not behind the firewall cover)?
(2) If it is manual can and SHOULD I upgrade it to PB?
PS...when I get to good weather and clean up the '68 I'll update my picture to show both 427s side-by-side
I posted up a month ago with my new/old '68 big block purchase. This month I've spent time going over all the issues I have as this surprisingly good runner needs a lot of love and restore work over the next few years.
I have a few early questions (please be kind) as I've restored a C4 with my son in the past and own a fun C6 Z06). I have brake fluid leaking down the firewall "cover" and I know the master cylinder (MC) is original. Safety is always paramount as my wife likes to drive the manuals and these big blocks don't come cheap. PS...Just got my 68 AIMs manual from NCRS (what a great helper)!!!!
Two questions:
(1) If I can't SEE the brake booster in the engine bay attached to the MC, than my car IS manual braking right (i.e. it's not behind the firewall cover)?
(2) If it is manual can and SHOULD I upgrade it to PB?
PS...when I get to good weather and clean up the '68 I'll update my picture to show both 427s side-by-side
Last edited by z06roadkiller; Dec 26, 2021 at 10:57 AM. Reason: more info
Melting Slicks
Joined: Nov 2006
Posts: 3,416
Likes: 1,825
From: Apple Valley, MN
The only dumb questions are those that don’t get asked.
You are correct that if you don’t see the booster (it is very obvious in the engine compartment if you have one), you have manual brakes.
If you/your wife are happy with the braking pedal effort today, no need to add the power assist. Conversely, if you want the braking pedal effort to be decreased, bolt one on. Note that you’ll need to swap the brake lines from the MC to the distribution block and add the vacuum line.
You are correct that if you don’t see the booster (it is very obvious in the engine compartment if you have one), you have manual brakes.
If you/your wife are happy with the braking pedal effort today, no need to add the power assist. Conversely, if you want the braking pedal effort to be decreased, bolt one on. Note that you’ll need to swap the brake lines from the MC to the distribution block and add the vacuum line.
1967 Pedal Car Champion
Joined: Mar 2020
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From: US-PNW
I have brake fluid leaking down the firewall "cover" and I know the master cylinder (MC) is original. Safety is always paramount as my wife likes to drive the manuals and these big blocks don't come cheap. PS...Just got my 68 AIMs manual from NCRS (what a great helper)!!!!
2026 Loser of the Year
Joined: Sep 2013
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From: New Or-leens Loo-z-anna
The only dumb questions are those that don’t get asked.
You are correct that if you don’t see the booster (it is very obvious in the engine compartment if you have one), you have manual brakes.
If you/your wife are happy with the braking pedal effort today, no need to add the power assist. Conversely, if you e the braking pedal effort to be decreased, bolt one on. Note that you’ll need to swap the brake lines from the MC to the distribution block and add the vacuum line.
You are correct that if you don’t see the booster (it is very obvious in the engine compartment if you have one), you have manual brakes.
If you/your wife are happy with the braking pedal effort today, no need to add the power assist. Conversely, if you e the braking pedal effort to be decreased, bolt one on. Note that you’ll need to swap the brake lines from the MC to the distribution block and add the vacuum line.
It sounds like the rear o-ring seals in the master cylinder are leaking. There are kits to rebuild them and are easy to do IF the bore isn't pitted from rust. Pitting would require sleeving or straight-out component replacement. If you indeed have the original '68 master, don't core-trade it – offer it up to a restorer for the same core price (or more). You'll need to bleed the entire brake system after the master cylinder work.
(converting to a brake booster isn't fun/requires drilling holes in the firewall/takes up lots of space)
Is my vette stock?? HAHA
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
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Buy a master/ booster combo together. There are alot of mismatched pairs out there that dont work because of the plunger adjustment not being correct or not having the adjustable pushrod to do it and a manual master with the power booster. And some are just bad out of the box, mostly the reman ones you get from supply warehouses or box stores. I bought mine from TuffStuff. You need to buy the disc/disc model as they have them listed for drrum brake options as well. They are high quality, built in the USA and look good. You have to take out the seat and steering wheel to get under there easily. Taking out the column will make life easier. If you do take all this out, take pics along the way. In 68 they routed the harness 3 different ways so you need to take pics of it if you take out the dash pad. If you are restoring the car you may want to.
Use the advanced search to find the build threads on a manual to power conversion. Its pretty simple. Getting all the bolts out is the hard part. To swap you just have to egg shape the hole in the fire wall to match the metal support thats already there
Remember a lot of parts are one year C3 only but may be carry overs from the 67 C2.
Use the advanced search to find the build threads on a manual to power conversion. Its pretty simple. Getting all the bolts out is the hard part. To swap you just have to egg shape the hole in the fire wall to match the metal support thats already there
Remember a lot of parts are one year C3 only but may be carry overs from the 67 C2.
Team Owner
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From: Sitting in his Nowhere land Hanover Pa
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original born with M/C are worth a good bit. if original rebuild it. Lone Star Calipers is a great vendor for all of your brake needs. most vendors sell their stuff too
Melting Slicks
Joined: Oct 2003
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From: Dallas TX
St. Jude Donor '06-'09,'22,'25
If you have 4 wheel disks you shouldn't need to upgrade to power brakes if everything is working great. My BB '69 stops great with all original, new parts.
I had a local Corvette shop here in Dallas recently replace my master cylinder for less than $250 including parts and labor. Took them about an hour or so, and was so worth it.
I had a local Corvette shop here in Dallas recently replace my master cylinder for less than $250 including parts and labor. Took them about an hour or so, and was so worth it.
Last edited by TX427C3; Dec 27, 2021 at 11:58 AM.
Team Owner
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From: Sitting in his Nowhere land Hanover Pa
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Thread Starter
Racer
Joined: Sep 2006
Posts: 395
Likes: 31
From: Gurnee, IL
St. Jude Donor '12
Guys:
Thanks for all the suggestions...I'm sure the rear seal on the MC is worn out and probably really rusted. The braking is definitely harder that I'm use to but with time I'll get use to it. The last manual brake car I had was a '69 Chevelle SS396 that I got rid of late in college ('1984)....and wish I never did. So it's been awhile plus I'm manual steering so why not just stick to stock and use my muscles
I do have 4 wheel disks that are fairly new (looks to be within the last 2-3 years based on the shape of the caliper). I'll look into both ideas:
(1) Having someone rebuilt my original MC, or
(2) Buy a period correct rebuilt MC and sell my existing to a restore company
Either way I planning on putting in new brake lines while I have to bleed the entire system anyways.
Thanks
Thanks for all the suggestions...I'm sure the rear seal on the MC is worn out and probably really rusted. The braking is definitely harder that I'm use to but with time I'll get use to it. The last manual brake car I had was a '69 Chevelle SS396 that I got rid of late in college ('1984)....and wish I never did. So it's been awhile plus I'm manual steering so why not just stick to stock and use my muscles
I do have 4 wheel disks that are fairly new (looks to be within the last 2-3 years based on the shape of the caliper). I'll look into both ideas:
(1) Having someone rebuilt my original MC, or
(2) Buy a period correct rebuilt MC and sell my existing to a restore company
Either way I planning on putting in new brake lines while I have to bleed the entire system anyways.
Thanks
1967 Pedal Car Champion
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From: US-PNW
Melting Slicks
Joined: Oct 2003
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From: Chapel Hill NC
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My 66, 68, and 71 have manual brakes and I have no intention of converting them to power brakes, even though I'm getting older and weaker. I find it just take a minute or two for my leg to adjust to the pressure needed to adequatley stop the vehicle. I'm under the impression that your stopping distance will not change by adding power brakes- it just takes less leg effort.