Brakes

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Brakes

Postby Greybeard » Sun Aug 14, 2016 10:12 pm

Since I got this car on the road, I've felt insecure with the brakes. Monza disc, ford drums, unboosted master. They had a bit of air in them so I bled them and now pumping them no longer raises the pedal. I haven't gone out and tried to lock them up, but I have pushed them hard enough to feel like I was bending the firewall.
I haven't got much vacumm in this sucker, so assist seems like it'd be a pain n d a. The pedal comes hard still off the floor a ways, and higher than before I bled them, so I don't think I'm bottoming the master. I don't know if it has bleed back restriction in it, but lack of would create pedal height issue, not stopping issue,?.
Oops, my bad. I just assumed I had Monza brakes as it has 5 lugs, but the rotor is non vented.
1937 Chev 2dr sedan
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Re: Brakes

Postby avewhtboy » Sun Aug 14, 2016 11:15 pm

The brakes on these cars are sub par for today's roads traffic etc. Then add 200hp and 200 extra pounds and in my opinion you have a recipe for disaster if you are driving
much on the street.

I upgrade from manual to power using factory stuff and it gave me a lot more confidence but I went a lot further due to what I wanted to do with the car. I would start with a booster
if you think you have enough vacuum. Even if not they have electric vacuum pumps to take care of that.
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Re: Brakes

Postby chevyart » Mon Aug 15, 2016 10:17 am

mike i would first check under dash and i believe the rod going to master cylinder must be in the top hole for manual brakes to get the right leverage. secondly, the master cylinder bore should probably be aprox 7/8-1" bore size. you probably have the s-10 brakes and the s-10 master is a plastic one and should be the proper size (if you have that one). my buddy haS THAT SETUP AND IT WORKS FINE. THE ONLY PROBLEM WITH THAT IS IF YOU HAVE THE 2129 HEADERS, THE MASTER BRAKE LINES ARE VERY CLOSE TO THE HEADER TUBE. too big of a bore size equals too hard of a brake pedal and less brake pressure. jusr the opposite with a too small of a bore master. go to summit site and punch in phrase Quick Fix : master cylinder bore size FAQ. hope this helps. art
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Re: Brakes

Postby hammerdown7 » Mon Aug 15, 2016 11:03 am

If your rotor is non-vented you have re-drilled Vega rotors and a small master, adding larger rear drums only makes it worse. Your bolt circle is most likely 5 on 4 1/2 so that the re-drilled front rotors match the rear bolt circle.

Dick
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Re: Brakes

Postby chevyart » Mon Aug 15, 2016 12:58 pm

that makes sense what dick has just said. guess the next, eaSIEST STEP WOULD BE THE MONZA VENTED FRONT ROTORS, ALONG WITH THE 76 AND UP MONZA MASTER CYLINDER(7/8" BORE). BEYIOND THAT IS THE AFTERMARKET STUFF ( OR )THE S-10 SETUP WHICH WOULD GIVE YOU BACK THE 5 LUG ROTORS AND BETTER BRAKES AND BETTER BALL JOINTS. THE MONZA PARTS WOULD BE ONLY FOR 4 LUG SETUP. ART
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Re: Brakes

Postby Greybeard » Mon Aug 15, 2016 2:08 pm

I was up all night reading about small brakes in general. Found a discussion about a CW Vega and changing pads to ceramic. Also found Mustang guys changing from power to manual brakes and they mentioned this company: http://www.ctbrakes.com/pads.asp?Make=C ... del=MONZAh you can go to products, and then brake material to read about them.
I called this morning and had a good conversation with "Mike". The basic pad is a ceramic/carbon material that produces a stronger bite upon initial application, and a linear braking. The "linear" part sounds good. It feels like it would be impossible to lock this thing up. They recommend the pad for towing, fast street cars, and drags. The basic pads are rotor friendly, quiet, and produce little dust. The next ones up have a stronger initial bite, and get stronger as the heat builds. Recommended for auto cross. They can be noisy, and dusty.
Question? Are the solid rotors available?
1937 Chev 2dr sedan
1966 Chevy El Camino (daily driver w/300K miles)
1966 Chevy V8 Corvair https://greybeard.shutterfly.com
1972 Vega GT
1985 Corvette
1999 Safari Sahara 30' with Cat 330
1999 Jeep Cherokee 'toad'
Next: 1964 289 slabside Cobra, LS525 power
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Re: Brakes

Postby hammerdown7 » Mon Aug 15, 2016 3:32 pm

Both solid and vented are becoming very hard to find for stock h-body's. Last pair of vented on eBay sold for $149 I believe.

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Re: Brakes

Postby Greybeard » Mon Aug 15, 2016 4:02 pm

1937 Chev 2dr sedan
1966 Chevy El Camino (daily driver w/300K miles)
1966 Chevy V8 Corvair https://greybeard.shutterfly.com
1972 Vega GT
1985 Corvette
1999 Safari Sahara 30' with Cat 330
1999 Jeep Cherokee 'toad'
Next: 1964 289 slabside Cobra, LS525 power
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Re: Brakes

Postby Smiley » Mon Aug 15, 2016 6:13 pm

you are better off switching to S10 brakes up front, if your wheels are drilled for 4 3/4" x 5.
larger dia vented rotors, already 5 lug, parts are cheap and widely available.
sell the solid rotors to recoupe some of the cost.
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Re: Brakes

Postby chevyart » Tue Aug 16, 2016 11:17 am

mike guess you will be in the state of confusion for a few days trying to figure these choices out. a few years ago i haq a similar braking problem, but with my 67 nova dragcar. had the big ford brake shoes on the back and the smaller chevy nova front brake shoes. car really didnt want to stop good and i was coming through the 1/4at aprox 122 mph. and on a short stopping area, downhill, in new jersey it was not funny. i was too lazy to do a simple disc brake conversion(A NO BRAINER) SO I FOUND A COMPANY IN TEXAS CALLED PRAISE BRAKE DYNO that makes kevlar lined brake shoes that give an extra 15 to 20 % more stopping power. i put them on and the car really stopped a whole lot better. problem solved. just had to actually break them in before they worked properly. was hard to do that on a strictly drag car, but i did it. just some food for thought. good luck. art
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Re: Brakes

Postby Greybeard » Tue Aug 16, 2016 1:35 pm

Yes, I will be in a state of confusion for a bit. Don't want to reinvent the thing, and am inclined to try the pads/linings change first. I remember my Cosworth brakes took all you had to stop hard. We've got a lot of beautiful winding roads out here, and I was hurrying the thing through the forest. I was prolly 30 over posted, had just got into the throttle and came out of the corner to find someone doing a U turn and crossways in the road. Got stopped, but I remember I was pushing as hard as I could on those brakes. Didn't lock up.
At the track last month, I was using all the shutdown area, about 1/2 to 5/8 of a mile. There are guys running a buck and a half that aren't throwing out the laundry on this track.
1937 Chev 2dr sedan
1966 Chevy El Camino (daily driver w/300K miles)
1966 Chevy V8 Corvair https://greybeard.shutterfly.com
1972 Vega GT
1985 Corvette
1999 Safari Sahara 30' with Cat 330
1999 Jeep Cherokee 'toad'
Next: 1964 289 slabside Cobra, LS525 power
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Re: Brakes

Postby Monza Harry » Tue Aug 16, 2016 4:53 pm

GB, If you have solid rotors you have like Dick said the "F :censored: D bolt pattern so before going to the S10 setup you will need to see if your wheels are dual pattern or Uni-lug before going to the Chevy setup or at least find a buyer for your wheels and rotor parts to help offset the cost of new wheels, brakes, and, well we all know where this is heading! $$$$$ Keep us posted on which way you go and how it turns out. Harry
I'm not a hoarder I'm a preservationist 78 Monza Spyder (Soon To Be 2+2 with Spoilers)
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Re: Brakes

Postby hammerdown7 » Tue Aug 16, 2016 7:32 pm

Another thing to keep in mind is high performance brake pads will wear the rotors quicker, some times much quicker with heavy braking, not good when replacements are scarce.

Dick
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Re: Brakes

Postby Greybeard » Fri Aug 19, 2016 1:45 pm

Yesterday morning I went out early to a nice straight, level, rural road to actually try a panic stop. I'm easy on brakes, not waiting to the last 75' to start braking as I see lots of people do. In 310,000 miles, my Elco has had only two brake jobs, and both initiated by leaky wheel cylinders. So thinking I needed to to actually see what happens, I tried a true panic stop. The rears locked up, and the pedal pressure wasn't too severe. Coulda pushed a lot harder. I looked at the Monza ventilated rotors yesterday, and I can't see how they could possibly be drilled in a 5 bolt pattern without the four ribs interfering with the studs. Checked my wheels yesterday as well. The are dual pattern and using 5 on 4.75.
For they time being, I'm going with the pad change. I only put maybe 1000 miles on it a year and I'm pretty easy on brakes. Also, at 73 years of age, I prolly won't see 20,000 miles before they take it away from me. However, if the pads don't work out, then it sounds like the S-10 stuff is the answer.
I'll report on the brake pads when I put them in. May be a bit. Fuel pump failed yesterday. On my "want" list is changing to a Camaro fuel tank, in tank pump, to get ready for the FI on my list. It may be time, as the present pump cost the better part of a change over.
1937 Chev 2dr sedan
1966 Chevy El Camino (daily driver w/300K miles)
1966 Chevy V8 Corvair https://greybeard.shutterfly.com
1972 Vega GT
1985 Corvette
1999 Safari Sahara 30' with Cat 330
1999 Jeep Cherokee 'toad'
Next: 1964 289 slabside Cobra, LS525 power
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Re: Brakes

Postby Monza Harry » Fri Aug 19, 2016 4:38 pm

Greybeard the rotors can be drilled, but not with an electric drill motor [electric hand drill] or even an homeowner drill press. This requires a milling machine and a few cutting tools like an end mill to spotface through the ribs you mentioned and a welder to fill the one hole that will interfere with the 5 bolt pattern layout. This is tight and that is the reason for using the F :censored: D/Morparts required pattern the Chevy pattern will hit the raised "hat area" it is that tight. If you find the right guy on a Friday Night you may get this done at a machine shop for as little as a case of beer! :beer: Harry
I'm not a hoarder I'm a preservationist 78 Monza Spyder (Soon To Be 2+2 with Spoilers)
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