I've been considering fitting a brake booster to my '69 350 manual, as the braking is very poor. I'd like to go for the kit from Corvette Central or maybe chrome master cylinder and booster from Ecklers. I have had some good advice from the forum before on how inaccessible it is under the dash, but does anyone know if a non-power brake car was equipped to take a booster, so that all the holes were already drilled, or is this something you'd have to do before fitting the servo? It sounds like the job would be a lot more difficult if you had to do this from inside the car. Thanks.

 

I think you'll "have" to drill the holes and do it from both sides of the firewall....

But.........that's what I get fur thinking !

Experts ????? Chime in if I'm wrong...

 

if you are going to go through all that, put on a Hydro Boost rather than the vacuum assist....jmho..

 

Try using the brake booster gasket as a template as to where to drill the holes.

http://www.parts123.com/parts123/yb....Z5Z5Z50000050G

 

Yep gotta drill, I have the instructions for the hydroboost sitting on the shelf and it shows on non power cars you have to relocate the holes down and then move the point where it attaches to the pedal down as well. If you are going to go to the trouble of drilling the firewall, absolutely go with hydroboost. I got the booster, lines, and new mastercylinder for 350 bucks.

 

Manual brakes firewall;




Modified for power brakes firewall;



I addition to this, the pushrod has to be relocated on the pedal arm to the power position. You will need a power master cylinder as well

I looked into going power on my '69 but decided against it as I did not want to modify the firewall and give up the engine space the booster requires. Hydroboost was not an option as I wanted to keep it simple.

I stayed manual. Used the aluminum 7/8 bore Wilwood master and my car stops great - I can lock up the fronts if I really try. Saves a good 5-7 lbs as well

I'd troubleshoot your manual system first before making any permanent changes.

Good Luck, Ed

 

I had the same problem on my 71 the brakes just didnt feel safe.
After I saw how big of PITA installing a vac boosted system was going to be I found this
http://www.abspowerbrake.com/ehpm.html
My car is not only a manual brake car but a manual steering car to so no hydra boost.
The only problem with the ABS system is the nasty price.

 

Thanks to all who posted information regarding fitting power brakes. It looks like a big job all right - the ABS option looks easier to fit, but although I e-mailed the company to find out the cost, they didn't get back to me. I've had new calipers and kits fitted to the manual brakes but the braking efficiency is poor. My inclination is to go for the servo and power master cylinder, but from what you've all said it's going to be a difficult job to take on.

Regards, Barry.

 

Barry,

I'm by no means an expert but I have installed a hydroboost on my 72 big block, originally equipped with power brakes. Many years ago I tried doing the vacuum booster upgrade on a friend's manual brake '73 but gave up when we saw how much work it would be.

I purchased the hydroboost from a parts house, choosing a Chevy 1500 pickup unit because it had the lowest core charge. I bought all the parts and pieces from different vendors based on their prices (same parts, just different prices). One of the pieces I needed to buy was the mounting flange. For a power brake equipped 72 Corvette, this is the flange:


For a manual brake equipped Corvette, there is a different flange available:


The vendor that sells these flanges recommends you use an aluminum master cylinder with the two-bolt flange (for obvious reasons.

As I said, I'm not an expert but it looks like you can convert to power brakes without hacking up the firewall but you might want to ask the experts here on the forum about your master cylinder selection. I believe your manual cylinder has a 7/8" bore while the power brake cylinder is 1-1/8" bore. Your pushrod is going to be in the higher leverage position on the pedal so I don't know if that makes a difference. I'll let the experts chime in.

 

Hi Bob,

Thanks for the information on fitting a hydroboost. This seems to be a good solution, but do you or does anyone know where I can buy one, and all the parts I'll need?

Regards,

Barry.

 

A former CF forum member (durangoboy) sold me mine... i can get you his #'s if you pm me. the HB was $150 tested and all modifications done, and he has a parts list from summit that will run about $150 also... so a total of about $300 will get you into a HB... and they are nothing short of:wooho o:

 

Hydratech Braking Systems, Tallon Hydraulics and Vette Brakes & Products carry complete systems. I know that Tallon Hydraulics carries the manual brake mounting plate but the other two may have them as well. These systems are all more than double what PaulDana paid so if durangoboy still has the system, that's a good option. Here are the three sites (I mention them in alphabetic order but VB&P is a forum vendor so you might try them first):

http://www.hydratechbraking.com/C3Corvette.html
http://www.tallonhydraulics.com/stor...cPath=54_65_78
http://www.vbandp.com/C2-C3-Corvette...ke-Assist.html

 

I know the topic has already been broached in this discussion, but I just replaced the vacuum booster on my 1972 and man was it a pain getting under the dash, even with the seats out!

 

I have removed the seats, steering column and dash and it still isn't a picnic.

 

Just a note of caution.... Normally, the manual braking system for the C3's is just as effective as the power brake system; but, the PB system requires much less effort to apply. If your brakes don't stop properly, it may be due to other issues: perhaps only one half of the system is working (front or back not working); perhaps you have a PB system master cylinder which has a different pressure schedule than the manual unit; maybe the flex hoses at the calipers are shot and not passing adequate apply pressure.

I'm only suggesting that you verify that all the mechanical parts of your manual system be checked out thoroughly before you throw dollar$ at the problem...only to find that they work no better than before. Good luck with the solution.

 

Putting the brake booster on a non power brake car is not that bad.if you have an auto trans its even easier.do a search on it.hydroboost may work good but I couldn't stand the looks of it under the hood.took about 8 hours to convert it over.bleeding the brakes now thats another story.I took out the steering column and driver seat to make it easier to get at the brake pedal.

 

Thanks to all who advised me on fitting power brakes. I think the Hydroboost is the best option from what you have said. It seems the vacuum is too much trouble, but I take rugerm44's point that the Hydro doesn't look original under the hood. I took the Vette out today for the first time this year, and checked out the brakes again. There's a definite pull to the right. I've had all the brakes overhauled with new kits and calipers, but as 7T1vette pointed out, it could be that the manual brakes are faulty to start with. There's no air in the system, but something must be wrong. Before buying the Hydro I also have to fix the leak from the power steering pump. After that's all been fixed, I'll shop around for the best Hydroboost. Regards, Barry.

 

at first I thought that also, really did.... but with time........, now when i see the big old drum, looks antique now to me.... just saying... beauty is in the eye of the beholder i guess..... heres mine, some will like, some wont...

 

Pauldana - thanks for the picture of the hydro unit. It really doesn't look out of place at all, it fact I think I prefer it to the drum. I have other non-original things there anyway such as an MSD 6AL, so originality is not crucial, especially considering the difficulty of the alternative. I've got to attend to the brakes and steering before I buy the hydro, but I'm happy now that this is the choice for me. Regards.

 

If you love the look of a pure stock Corvette, this isn't an option. I've had mine for 34 years and it wasn't pure when I bought it. Never thought about the beauty of the vacuum booster, just the space it took up. Not ready to modify the heater side but the brake side is a lot more open...