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Discussion Starter #1
Looking to upgrade the brakes in my 69 GTO from regular old drum brakes (not power) to disk brakes all the way around. So I have a few questions I'm hoping someone can help with.

- Is it worth upgrading to power disk brakes? If so where does the vacuum hose connect to? Intake? Carb? I've read that with high lift cams (which I have) there might not be enough vacuum for the brake boost. Really don't want to add an electric vacuum pump unless its very well worth it.

- Is it worth spending the money on the slotted / drilled routers? I just drive the car around town, on the highway ect.

- Any other thoughts / suggestions would be much appreciated.
 

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Disc brakes are good, no doubt about it. But there are alternatives.

Power brakes are also a good idea.
First you need to measure your vacuum to determine what type and size of booster you will need.
Or you can go with a hydro-boost system if your vacuum is to low for a vacuum booster.

Drilled and slotted rotors are intended for heavy brake use such as towing or racing. Unless you plan to do either then its mostly the bling factor. Cheap drilled rotors have been known to crack so get the best you can afford (Brembo?)

Front disc brakes changeover is fairly common and easy to do. The rears are a bit different and there are various options using other GM models (Corvette, Cadillac, Camaro). Put some thought and research into it.

Me, I went with the Muscle Car Brakes for my drum brake car. I've driven the car since new and never felt the need to change.
 

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Discussion Starter #4
Thanks you guys. So with a little more investigation I learned that 15”-18” of vacuum is required for a brake booster. Some get away with less but I don’t want to screw around when it comes to being able to stop. So I found a threaded plug on the back of my intake (edelbroke performer RPM), got myself a vacuum gauge, took out the plug and checked vacuum at idle (900 rpm). Got about 7” of vacuum. Yes I have a moderate street/strip cam in it. So that’s not going to work. So I decided to go with an electric vacuum pump that I’ll mount on the firewall and go with 4 wheel power disk brake conversion kit from Ames. Not the drilled and slotted rotors. Although they might look cool behind my Craiger Ss wheels I just think it would be way overkill for the driving I do. Thanks again!
 

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Look into the hydro boost system. Utilizes hydraulic fluid from the power steering pump instead of vacuum for the power brakes. Astro mini vans, HD Chevy trucks use this system. From what I understand its a much better system than a vacuum booster.

 

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Unless you're autocrossing or stopping it from 140mph drags, Front disc/rear drum with a modern master and prop valve will stop you plenty.
I'm sure it will be an unpopular opinion, but rear disc brings more pain than benefit. You're either going to have an actuated caliper or a rotor/parking brake drum combo back there. More to go wrong, and doesn't like sitting around if you live where winter is long.
Not to mention nice ability to control tire spin off the line with drums if you've a mind to.
So much of "4 wheel disc" on a 60's muscle car is the equivalent of drilled/slotted rotors.
OK, pulled on my fire retardant undies...flame away :)
 

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In the mid '70's I bought a new Plymouth Duster, 318, 3 speed manual on the floor (I converted to Hurst), manual steering and manual (non-power) front disc brakes from the factory. I never had a problem stopping that car, even after a 340 swap, even at the end of the 1/8 strip we have. Only reason I see for PS is for a quicker ratio and and being able to turn ithe wheel faster. When I do the brakes on my GTO (factory power discs) I wll have put in my Lunati Voodoo cam which has <10" vacuum according to Lunati. I'm already researching a swap over to manual discs, getting a master cylinder with the correct bore I need and raising the brake pedal. I was 20 when my GTO was made and can still walk several miles so I find no need for power assist. (My late father-in-law had a new '72 Ford Torino with factory frt disc brakes and no power booster from the factory) Not uncommon to have discs w/o a power booster.

I agree with Mine'sa66 on his post as well as O52 on the MuscleCarBrakes link. Also try :: #1 Race Specialist in The World :: � for some good pads and shoes. Best of luck with your car.
 

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EdR, You really don't need one of those disc kits as you can use the entire set-up from another '69 with discs as you probably know. I did not like the "old" calipers on my '68 and used a setup from a '69 Grand Prix for the single piston caliper and D52 pads (much easier to find parts for and less expensive.)
 

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Discussion Starter #10
Just when I thought I had my mind made up!! Hahaha. Thanks so much for the input. Very interesting. I guess I could always go with just the front disc set up without power booster. See how I like it. And add as a I go if I want.
 

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Just when I thought I had my mind made up!! Hahaha. Thanks so much for the input. Very interesting. I guess I could always go with just the front disc set up without power booster. See how I like it. And add as a I go if I want.
I would go with the power. Modern 2 chamber master with prop valve. 11" smooth rotors with single piston calipers. The pedal feel and the stopping will be just like your "regular" car. That kit is available most everywhere. Not too expensive, not real hard to do. As others mentioned, it's basically gathered up early f-body disc brakes. Like you said, you can always go back and add the rear disc if you really think you're missing something. 1 downside...you'll have to re-change the prop valve if you do this. Diffferent one for disc/drum vs disc/disc. But, they're cheap and easy.
 

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Looking to upgrade the brakes in my 69 GTO from regular old drum brakes (not power) to disk brakes all the way around. So I have a few questions I'm hoping someone can help with.

- Is it worth upgrading to power disk brakes? If so where does the vacuum hose connect to? Intake? Carb? I've read that with high lift cams (which I have) there might not be enough vacuum for the brake boost. Really don't want to add an electric vacuum pump unless its very well worth it.

- Is it worth spending the money on the slotted / drilled routers? I just drive the car around town, on the highway ect.

- Any other thoughts / suggestions would be much appreciated.
Just thought I would throw this out there. I bought this 4 wheel disc setup on ebay for around $1200. For the amount I drive it, I didn't need anything expensive. Stops on a dime and the brake pads will last me 10 years lol. Easier than I thought to install, tho my engine was out at the time. You will need to make/buy and bend some of your own brake lines. Like from your rear pumpkin to their rear flex line, and the front proportioning valve to the rear block thats mounted on your frame by below your steering column. I did it for both cosmetic and function since I had manual drum brakes on all 4. But if you are not able to see your discs because of oem rally's...I would stick to fronts only. Well worth it to me.
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I'll throw in my 2 cents here. What rim size are you planning to run? I upgraded my front brakes a few years back to a Wilwood disc with 4 piston calipers and it fit under 15 inch stock style rims. I left the back brakes stock drum. Unless you are going to autocross your car, you really don't need rear discs. My car didn't have power brakes either and I left it that way to prepare for future upgrades (those are coming sooner than I expected due to a failed engine). I used a newer style master cylinder with a disc/drum proportioning valve and everything plays very nice together. The brakes are great compared to what they were. Nice part about the Wilwood conversion is you don't need to change the spindles. You do have to drill and tap out the top guide hole but that is pretty easy if you take your time. There is already a big hole there, you just need to make it bigger and tap it out. One thing to keep in mind if you plan on leaving your brakes manual rather than power. Be sure whatever master cylinder you choose is designed for manual brakes. This piston size is different. Also, your original brake lines to the cylinder will not work and I couldn't find a pre-bent set for manual brakes. I bought the power brake line kit from inline tube and had to modify the front lines to match up with the master cylinder. This was not hard, just took time to get it right.

I have an old thread on here from a few years back that shows some of the conversion.
 

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Discussion Starter #14
Thanks very much everyone! I have 15" Craiger SS wheels. The disc brake packages at Ames (my preferred source of parts) is on back order until August so I have a little time to think about all the input. At a minimum I'll be doing disc brakes up front and I really like the idea of the power brakes. Although its not a numbers matching car i do try to find a balance between keeping true to the original car, and performance, so I'm not to thrilled with the idea of adding an electric vacuum pump to make the booster work properly. Although I guess I could hide it low on firewall someplace. Also just one more thing to fail.
 

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Thanks very much everyone! I have 15" Craiger SS wheels. The disc brake packages at Ames (my preferred source of parts) is on back order until August so I have a little time to think about all the input. At a minimum I'll be doing disc brakes up front and I really like the idea of the power brakes. Although its not a numbers matching car i do try to find a balance between keeping true to the original car, and performance, so I'm not to thrilled with the idea of adding an electric vacuum pump to make the booster work properly. Although I guess I could hide it low on firewall someplace. Also just one more thing to fail.
Before you go the whole electric vac pump or even hydroboost. Try an old fashioned vacuum reserve canister. Your engine will make good (decent anyway) vacuum up off idle. A reserve canister is just a simple chamber with a one way valve. It stores vacuum. It's not a perfect solution, a lot of pedal depresses in a row without bringing the rpms up will deplete it, but there's one heck of a lot of stout engines out there that get by with this type of system. Cheap, easy and no moving parts.
 
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