I want to replace the stock break booster on my 69 with a blown 502. I need the clearance for the valve covers.

What are some suggestions? I've seen the smaller boosters (diameter) as well as the hydraulic boosters?

I'd really like to see some pictures or listen to some ideas.

Thanks folks.

PS, any assembly tips ??

http://i7.tinypic.com/281c3y9.jpg

That motor is saweet:thumbsup: I'm using a 9" and have no problem with my power brakes. Especially with those valve covers that you have which are angled, you shouldn't have any problems. I have pics of mine in my sig.

I would seriously look into hydroboost. I am putting it on mine.

I recently upgraded my power drum to power disc on my supercharged chevelle. The booster was a 11" single diaphram, it fit with tall valve covers but the cover had a dent to miss the booster, a stud girdle still fit tho. The brakes sucked when i was finished. Not 100% sure but with around 8" of vacuum i dont think the booster was working. Anyway to make a long story short i changed to manual discs and its 100%. Not like i thought it would be, it doesnt take 2 feet to stop at all. Just thought u might want to think about manual as it opens up a lot of room in the engine bay and they work well. Just food for thought, i also thought id never lose the power but it really isnt that bad.

I agree that the hydroboost is a good system. I couldn't use it because of my type of steering pump and looking at that picture, it's hard to tell if it has power steering and where the pump is. Hard to tell with the driver's side alternator.

What do you currently have for brakes?

Cheapest option is to go manual brakes if your calipers have the proper piston area to make that an option. If you are still running stock discs a 15/16" bore master cylinder will work just dandy and the pedal will not be all that hard. I drove my car with that configuration for quite a while.

A hydroboost is a fine option too but much more expensive, I'd try going manual first. I run a hydroboost now only because my C4-PBR calipers required more force than my right leg could muster in a manual configuration. A 15/16" bore MC was too hard, a 7/8" bore MC was OK for effort but the pedal stroke was too long and put the pedal near the floor-- so I had to go power. The hydroboost works fantastic, but I'd still prefer a manual setup but that's not really an option unless I change calipers.

Troy, I must be ignorant because I didn't know you were running hydroboost with your system(even though it's right there in your signature). I didn't think, for whatever reason, that the type-II was compatable with it. Did that require a lot of your engineering skills?

I recently upgraded my power drum to power disc on my supercharged chevelle. The booster was a 11" single diaphram, it fit with tall valve covers but the cover had a dent to miss the booster, a stud girdle still fit tho. The brakes sucked when i was finished. Not 100% sure but with around 8" of vacuum i dont think the booster was working. Anyway to make a long story short i changed to manual discs and its 100%. Not like i thought it would be, it doesnt take 2 feet to stop at all. Just thought u might want to think about manual as it opens up a lot of room in the engine bay and they work well. Just food for thought, i also thought id never lose the power but it really isnt that bad.I appreciate your post, because I just dropped the tall deck 632 inch motor in my Chevelle, and it also has the tall valve covers for clearing the stud girdles, and I've been thinking about using manual brakes too.

But do I need to do anything different with any other brake parts such as the rod that goes to the master cylinder since I'm doing away with the vacuum booster??? You can send me a PM if you like. I don't mean to hijack this thread by getting too much off topic.

Troy, I must be ignorant because I didn't know you were running hydroboost with your system(even though it's right there in your signature). I didn't think, for whatever reason, that the type-II was compatable with it. Did that require a lot of your engineering skills?

Works great with the Type-II. No special requirements for plumbing in a hydroboost except making sure you route the lines correctly and use hoses rated for the pressure. Only thing to watch for is how you plumb the return lines especially if you use a T-fitting, if you plumb it wrong the P/S return can back up into the hydroboost and cause it to apply the brakes lightly as you rev the engine because of fluid backpressure.

Manual brakes are still my #1 choice as it offers the most communicative pedal feedback. When that isn't a viable option (such as my PBR calipers which require loads of line pressure to clamp on the pads decently) then the Hydroboost is my #2 choice. TONS of assist and better pedal feedback than any vacuum booster I've ever used.

Billy,
Don't worry about hijacking the thread. I also think that just changing to manual brakes might be the best option...

I have stock disks on the front and drums on the back.

Like Billy asked, is there anything special to do to remove the power breaks?

Like Billy asked, is there anything special to do to remove the power breaks?

Need a different brake to MC pushrod, need to move the pushrod to the upper pivot on the brake pedal, need to readjust the brake light switch, and need new MC to distribution block brake lines.

You may also need a new master cylinder, power MC's typically have larger bore sizes and manual MC's smaller bore sizes.

What brakes do you have on the car now? If you're running factory discs up front and drums out back a MC with a 15/16" bore works great, a MC off a 77 Malibu with manual brakes is the ticket.

I have Baer disc brakes brakes on all four corners of my Chevelle, and the guys at Baer told me that the M/C that they supplied me with which came with that system can be used for power brakes or manual.

I have Baer disc brakes brakes on all four corners of my Chevelle, and the guys at Baer told me that the M/C that they supplied me with which came with that system can be used for power brakes or manual.

That's what they told me too with their provided 15/16" bore MC... good luck. I tried it and my pedal was extremely hard. I could stop the car "normally" with a decent amount of leg effort but it was extremely hard to push on the pedal hard enough to make a fast panic stop-- it was what I would call a "two-footer." I tried a smaller 7/8" bore MC and while the effort was reduced to a more reasonable level the travel was now so long the pedal was almost on the floor when stopping hard.

The C4-PBR calipers that Baer uses on their Track and Serious Street setups just don't lend themselves to a manual MC because of their small piston sizes mean they have high pressure requirements to generate the pad clamping force. Combined with our heavy cars that means lots of leg effort is needed. The C5-PBRs should be a little better because their pistons are larger but I have not tried a set of those with a manual MC.

That's what they told me too with their provided 15/16" bore MC... good luck. I tried it and my pedal was extremely hard. I could stop the car "normally" with a decent amount of leg effort but it was extremely hard to push on the pedal hard enough to make a fast panic stop-- it was what I would call a "two-footer." I tried a smaller 7/8" bore MC and while the effort was reduced to a more reasonable level the travel was now so long the pedal was almost on the floor when stopping hard.

The C4-PBR calipers that Baer uses on their Track and Serious Street setups just don't lend themselves to a manual MC because of their small piston sizes mean they have high pressure requirements to generate the pad clamping force. Combined with our heavy cars that means lots of leg effort is needed. The C5-PBRs should be a little better because their pistons are larger but I have not tried a set of those with a manual MC.Uh ho, then I guess I'll have to change my plan of going with manual brakes. I have the Baer "Serious Street" set-up. Thanks for the heads-up. I guess it's time for me to purchase a 7" booster, and hopefully the 268/271 degree @ .050 camshaft that's in my engine will allow enough vacuum to operate the power brakes.

Maybe you should take a vacuum reading before making your decision. I went thru the same situation. When I almost wrecked the car twice in traffic because I had to literally stand on the brake pedal to stop the car, I decided the Hydroboost was the answer. And it works awesome. A couple a friends with high hp cars went manual and are unhappy with the results. A small booster with low vacuum will probably be worse.
If your already have power steering (I didnt see it in the pic), you should seriously consider Hydroboost. Ya, its expensive, but how much did we spend to go fast?? Hydroboost is about 3-5% of that to stop fast.

As for me, you guys have been very informative in this thread, and I just went on the summit racing website and ordered a hydroboost set-up. They sure aren't cheap (as was mentioned). $600 & change for a powdercoated one, and that's the model that doesn't even include the master cylinder, ( I already have one) but I agree that since I've already spent tens of thousands of dollars to go fast, what's another several hundred dollars to have adequate stopping power for safety reasons? I'm sold. Thanks for all the tips guys! I hope that your advice has been as helpful to others in this thread ( esecially to the thread originator) as it's been to me. You guys have obviously prevented me from making some time consuming and costly mistakes. And with winter on it's way, time is of the essence for me right now! :thumbsup:

One piece of advice, completely flush your power steering system prior to installing the hydroboost and only run genuine GM over the counter PS fluid. ATF will foam too much and make the booster noisy and inconsistent.

One piece of advice, completely flush your power steering system prior to installing the hydroboost and only run genuine GM over the counter PS fluid. ATF will foam too much and make the booster noisy and inconsistent.Okay, got it. My pump, and steering box are brand new, and haven't seen any fluid yet, so once again, your advice is right on time. Does the hydroboost set-up normally make any sound that can be heard from inside or outside the car?

That's what they told me too with their provided 15/16" bore MC... good luck. I tried it and my pedal was extremely hard. I could stop the car "normally" with a decent amount of leg effort but it was extremely hard to push on the pedal hard enough to make a fast panic stop-- it was what I would call a "two-footer." I tried a smaller 7/8" bore MC and while the effort was reduced to a more reasonable level the travel was now so long the pedal was almost on the floor when stopping hard.

The C4-PBR calipers that Baer uses on their Track and Serious Street setups just don't lend themselves to a manual MC because of their small piston sizes mean they have high pressure requirements to generate the pad clamping force. Combined with our heavy cars that means lots of leg effort is needed. The C5-PBRs should be a little better because their pistons are larger but I have not tried a set of those with a manual MC.

How do you like your FAST set up? I am also running FAST EFI. We should compare notes one day. Would be fun. I did not see your name posted..

Okay, got it. My pump, and steering box are brand new, and haven't seen any fluid yet, so once again, your advice is right on time. Does the hydroboost set-up normally make any sound that can be heard from inside or outside the car?

Depends on what lines you use. If you use braided stainless teflon lines on the high pressure side as I did, a little bit of power steering pump noise can make it up into the passenger compartment during low speed turning. It's not annoying, but you will hear a bit of noise. If you use the fabric braided lines on the high pressure side (like from Aeroquip) the unit will be a little quieter. It also depends on the power steering pump used, some are just noisy regardless of the lines you use and you will hear it since the unit is bolted directly to the firewall. In OEM Hydroboost installations they've done all sorts of weird stuff to help keep the noise down, usually resorting to special hoses and bizarre looking inserts in the hoses. Then again, these aren't factory new cars with whisper-quiet exhaust systems so it has to be much louder for us to notice it.

How do you like your FAST set up? I am also running FAST EFI. We should compare notes one day. Would be fun. I did not see your name posted..

It's a good system, yes. A bit basic and lacking in some features I would like to have (A/C control tied in with IAC/timing control, TPS & RPM based decel fuel cutoff rather than having to do it via the VE table, timing retard based on IAT) but it works well. I bought it mainly because a good friend is very experienced with them and being my first EFI setup I bought what I could get help with. If I had to buy again today having more experience I'd go with AEM or Autronic as my primary choices based on the features they offer with BS3 or the FAST XFI as secondary options, since they're still a bit more "beginner" and more user friendly compared to AEM & Autronic which give you so many options you can very easily bugger up the entire system if you don't know what you're doing. :p

Re: Break Booster Suggestions???

Well it all depends on how strict and observant your boss is.

I've noticed that smokers get about 10x more break time than non-smokers, so maybe if you take up smoking, or even pretend to, you can boost the amount of break time you get throughout the day.

:D