Manual Brake Conversion with Pictures

[malibudave1978]

Re: Manual Brake Conversion on a 1980 El Camino

Worked on the new 7/8" bore manual brake master cylinder for a 1978 malibu, Wagner part number MC101252.

I ground off the front casting "imperfections"

I ground off the bottom casting "imperfections"

I painted it with some aluminum color paint I had from a previous project.

 

[t5montecarlo]

Re: Manual Brake Conversion on a 1980 El Camino

How did you manage to grind slow enough not to heat up the rubber parts inside? or did you first disassemble the unit?

 

[malibudave1978]

Re: Manual Brake Conversion on a 1980 El Camino

How did you manage to grind slow enough not to heat up the rubber parts inside? or did you first disassemble the unit?

I used a belt sander with 80 grit paper. I covered all the holes and piston to keep metal from entering the master cylinder. It never got overly hot that I couldn't touch it with my fingers.

 

[malibudave1978]

Re: Manual Brake Conversion on a 1980 El Camino

UPDATE:

I had trouble getting the brakes bled. I bench bled the system, but for some reason I couldn't get any pedal after I installed the system. I am going to use a bleeder kit to push brake fluid up to the master cylinder from the wheel cylinders and calipers. I will not be able to get to it until January 21st or 22nd, so stay tuned in until then.

Let me know if you have any questions.

 

[malibudave1978]

Re: Manual Brake Conversion on a 1980 El Camino

I want to let everyone know that there has been one issue with the calipers that I recommended from Speedway Motors. Its the Speedway Motors Big Bore Metric Calipers - PN# 91031040 $59.99 for each.

Here are the links that describe the issue.

http://www.maliburacing.com/forum/viewtopic.php?f=2&t=111382

http://www.gbodyforum.com/viewtopic.php?f=14&t=35367&sid=fe32adcefeafad16021984241fd71525

I have not had any problems with the ones I have bought. I have been told that these calipers are made by U.S. Brake when I first bought mine from Speedway Motors.

There are other options for big bore calipers, but they are a little more expensive from Wilwood.

http://www.speedwaymotors.com/Wilwood-GM-Iron-Metric-Calipers,24192.html

 

[6426yy]

Re: Manual Brake Conversion on a 1980 El Camino

MalibuDave
Have you got your brakes working yet?

 

[malibudave1978]

Re: Manual Brake Conversion on a 1980 El Camino

Not yet. Got the master bench bled, but I haven't had the time to get out to my father's house to finish it up.

 

[malibudave1978]

Re: Manual Brake Conversion on a 1980 El Camino

Purchased an additional new 7/8" bore master cylinder just in case the older new one I bought doesn't work like it is suppose to when I install it on the El Camino. When I was bench bleeding the older, new one, the front port for the rear brakes would suck the fluid back into the master cylinder after the piston was released. The rear port for the front brakes didn't have this issue.

Is this normal? I don't know, but I will find out from the new master cylinder that I bought.

I also bought a rebuilt, aluminum master cylinder, with a 1" bore, from a 1979 Buick Riviera with the optional rear disc brakes. I did this because the reservoir is larger, it can be retro fitted to the 7/8" bore manual brake master cylinder, and it matched the angle of the firewall. You don't need it for rear drum brakes, but I like the extra fluid capacity.

Let me see if I can get this wrapped up the weekend after Easter.

 

[malibudave1978]

Re: Manual Brake Conversion on a 1980 El Camino

I want to apologize to everyone. I haven’t found the time to get out and get this done.

But…

Here is a link to a person that carries new Proportioning Valves for Ford, GM, and Jeep.

http://proportionvalves.com/

Here is a link to a disc/drum PV for a g-body from the http://proportionvalves.com/ site.

http://www.carolinaclassictrucks.com/78-86-malibu-PV2.html

Here is a link to a disc/disc PV for a 2nd gen f-body that looks like it will work with g-body brake lines if you convert to rear disc brakes. Please call to confirm it will bolt in.

http://www.carolinaclassictrucks.com/79-81-TransAM-PV4.html

MOPAR MASTER CYLINDER RETROFIT
I may have found a way to retrofit a 7/8” mopar (1993 Dodge Shadow) master to a g-body for manual brakes. I have not tested this yet to see if this works.

For the Front Brake port on the Proportion Valve:
Edelmann 258350 - Adapter-Standard To Dual Master Cylinder - 3/16" Tube - 3/8-24 Female Inverted Flare Seat x 1/2-20 Male Inverted Flare

For the Rear Brake Port on the Proportion Valve:
Edelmann 258340 - Adapter-Standard To Dual Master Cylinder - 3/16" Tube - 3/8-24 Female Inverted Flare Seat x 7/16-24 Male Inverted Flare

I don’t know the length of the brake lines from the proportion valve to the mopar master, but flared lines are less than $10 each from the auto parts stores. It should be about 2 to 3 foot of line. A coat hanger can be used to find the actual length needed.

If this setup works, this will be the cheapest way to get an aluminum master cylinder retrofitted to a g-body.

Let me know if you see any issues with what has been posted above.

 

[malibudave1978]

Re: Manual Brake Conversion on a 1980 El Camino

Update.

A Wilwood master cylinder will not work with the angle of a g-body firewall if the Wilwood master cylinder is bolted directly to the firewall. It physically bolts up, but there is a hole at the bottom of the master cylinder that regulates the fluid from one reservior to the other. When bolted directly to the firewall, the angle will let all the fluid run to the back reservior and the front reservior is left almost empty.

The Wilwood master should work on a TRZ or TNT adapter plates because these adapter plates correct the angle of the firewall and allows the master cylinder to sit horizontal (level) to the ground.