Switching ABS to Conventional.

DOUG H

SCCoA Member
I was always under the impression that the gasket's primary function was to isolate the sound/vibration from the Teves pump/motor running from resonating through the whole firewall, secondary it was water/dust seal. I'd just cut out or make something that seal's it up, since that's all you'll need now.
 

gbabione

Registered User
I was always under the impression that the gasket's primary function was to isolate the sound/vibration from the Teves pump/motor running from resonating through the whole firewall, secondary it was water/dust seal. I'd just cut out or make something that seal's it up, since that's all you'll need now.
That's what I thought about doing. I've been looking around work for some rubber the right thickness
 

gbabione

Registered User
I have the booster and mc installed. I used both parts for a 90 base. When I was doing a bench bleed of the mc, I had to leave it sit overnight. When I went back to it, all of the fluid had leaked out. Shouldn't the ports be sealed off when no pressure is applied?
I read one person saying the rear ports are for the front brakes. Another person said the front ones are. The manual shows both fronts on the drivers side. Which way is it? What adapters are needed from the old system?
 

gbabione

Registered User
I have the booster and mc installed. I used both parts for a 90 base. When I was doing a bench bleed of the mc, I had to leave it sit overnight. When I went back to it, all of the fluid had leaked out. Shouldn't the ports be sealed off when no pressure is applied?
I read one person saying the rear ports are for the front brakes. Another person said the front ones are. The manual shows both fronts on the drivers side. Which way is it? What adapters are needed from the old system?
I figured out the leaking. I didn't think about the fluid having to be released back from calipers when brakes are released. Anyone have answers on which way to connect the lines.
 

MadMikeyL

SCCoA Member
The base model 90 had a diagonal split system, so one was for the left front and right rear, and the other was for the right front and left rear. This is why people generally use the crown Vic master instead of the tbird master, since that master bolts right to the tbird booster, and was meant for a front/rear split system like the SC has.
 

gbabione

Registered User
So what makes it diagonal, the way the lines are connected? Is there any detriment to connecting 1 front line to a front port and the rear and the other front line to the rear ports?
 

decipha

Registered User
There's quite a bit of balance that's needed to have a really effective braking setup. If the rears have too much bias then they will lock up before the fronts do under hard braking. If they aren't getting enough pressure then your stopping distance will be increased. You could also get brake steer if one side is getting more pressure than the other with a fully independent pressure setup.

Its up to you but no point in re-engineering what works.
 

gbabione

Registered User
So back to my original question. I read one person saying the rear ports are for the front brakes, another person said the front ones are. Which way is it?
 

MadMikeyL

SCCoA Member
Both and neither. One port is for the left front and right rear, the other port is for the right front and left rear. Save yourself a lot of trouble and buy the crown Vic master and a cheap 7mm shallow socket and be done with it.
 

DOUG H

SCCoA Member
There's quite a bit of balance that's needed to have a really effective braking setup. If the rears have too much bias then they will lock up before the fronts do under hard braking. If they aren't getting enough pressure then your stopping distance will be increased. You could also get brake steer if one side is getting more pressure than the other with a fully independent pressure setup.

Its up to you but no point in re-engineering what works.
I was under the impression that Crown vic's/Grand Marquis & base T-birds/cougars use a master that differs internally for use with drum rears vs the disc rears on the S/C/XR-7's. Drum brakes require less pressure, but more volume of fluid to apply then disk & this will cause a front bias when a drum type master is used for rear disc brakes. It cant develop enough pressure to fully utilize the rears & front will be doing 70% of the work. Any truth to that? It does make sense to me though.
 

MadMikeyL

SCCoA Member
That is handled by the proportioning valve, which will be different on a drum and disc brake car. On the base MN12 and Crown Vic master cylinders, that valve screws into the master, and can be swapped out to match what brakes you have. Unfortunately those valves are not sold new aftermarket, so your best bet for that is to get one off a car in the junkyard.
 

AdamG

SCCoA Member
So on my 93lx 5.0 and my buddy's 91 cougar ls 5.0 we have 4 line master cylinders. The master is also the proportioning valve basically. Both were drum brake cars, both now have cobra discs all around. Probably the best brakes I've ever had, super smooth, amazing peddle feel, no excessive nose dive, even nailing them at 150+.
 

decipha

Registered User
I'm not surprised. Going to larger front brakes and swapping from rear drums to discs would probably about cancel each other out in that the bias pressure should be about the same.
 
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