Yes another C3 brske issue...
Old Pro Solo Guy
Joined: Dec 2017
Posts: 8,095
Likes: 4,449
From: Marlton NJ
Factory C3 brake pedal has about 7" total travel.
Specified free play is roughly 1.5"?
Then 2.5-3.5" of brake travel. For PB.
Then should get firm.
2-3" off the floor?
Manual brakes are similar but they have more brake travel during use due to less leverage, on the pedal linkage itself.
So maybe 3.5-4.5" of brake travel, during use. It feels like double to the driver. The ratio difference is almost double.
Gets much closer to the floor before they get firm.
I never cared for the long stroke during braking.
It was far too slow for my autocross use.
But the long stroke and no booster did make for an excellent firm pedal and excellent braking feel or modulation.
Specified free play is roughly 1.5"?
Then 2.5-3.5" of brake travel. For PB.
Then should get firm.
2-3" off the floor?
Manual brakes are similar but they have more brake travel during use due to less leverage, on the pedal linkage itself.
So maybe 3.5-4.5" of brake travel, during use. It feels like double to the driver. The ratio difference is almost double.
Gets much closer to the floor before they get firm.
I never cared for the long stroke during braking.
It was far too slow for my autocross use.
But the long stroke and no booster did make for an excellent firm pedal and excellent braking feel or modulation.
Melting Slicks
Joined: Jun 2011
Posts: 3,116
Likes: 598
I have spent 2 days reading every c3 brake brake post on CF and google. With engine off I can build pressure after 2 pumps and pedal is hard. With engine running i can push pedal to the floor easily, ni firmness at all, and it return up when released. I can pull vacuum hose off booster and can hear the woosh of air.
I have replaced:
the booster twice
the master 3 times, two stock, now with Wilwood. Used push rod tool to measure correct length for adjustable push rod.
Calibers Wilwood 6R and 4R
Braided lines
added vacuum canister
I have bench bled the master, and bled the calibers using gravity, power bleeder, and old 2 person method. There is no air coming out of caliber bleed screws at all.
I have been fighting this for 5 years. Any ideas?
Thanks
I have replaced:
the booster twice
the master 3 times, two stock, now with Wilwood. Used push rod tool to measure correct length for adjustable push rod.
Calibers Wilwood 6R and 4R
Braided lines
added vacuum canister
I have bench bled the master, and bled the calibers using gravity, power bleeder, and old 2 person method. There is no air coming out of caliber bleed screws at all.
I have been fighting this for 5 years. Any ideas?
Thanks
Get the last bit of air out from the brake master cylinder. - CorvetteForum - Chevrolet Corvette Forum Discussion
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 1,095
Likes: 5
From: Oldham County Louisville, KY
I got the proportioning valve and will install tomorrow or Saturday. Fluid comes out of the rear bleeders pretty slow so I'm this is the issue. I'll update when complete.
Thread Starter
Burning Brakes
Joined: Mar 2006
Posts: 1,095
Likes: 5
From: Oldham County Louisville, KY
Have you ever tried this. Fixes spongy brakes for most C3 brake problems. And for wilwood rear calipers they need to be removed to bleed the first time. Seating completely vertical.
Get the last bit of air out from the brake master cylinder. - CorvetteForum - Chevrolet Corvette Forum Discussion
Get the last bit of air out from the brake master cylinder. - CorvetteForum - Chevrolet Corvette Forum Discussion
