I've searched...no answer on 5 lug swap...

[93project]

Guys, I've been searching for an answer here and haven't found what I needed so here goes....

I just got the 93 GT running with 02 spindles(track width I know), 02 ball joints, and PBR calipers up front, Ranger rear drums. Couldn't afford 4w disc just yet...
Now, The car will stop if I push the pedal to the floor but it does not respond like its supposed to if I do a hard emergency stop. It crawls to a stop..
I bled the lines as much as possible and still no change. I saw a thread about air being trapped in the caliper but these PBR's have their bleeders up high. I have a stock booster, brand new 93 master cylinder and I just changed and bled the rear drums and cylinders with no change.
A buddy of mine says the left caliper isn't holding pressure like it should so I'm changing it tomorrow but I doubt this will help. I know I didn't properly bench bleed the MC so I have someone else do that for me with a new MC. Still no change. All I did was replace the steel lines from the master and the prop valve going to each front caliper, new calipers, new rubber lines up front and new wheel cyls in back.
Is there anything I should have done? Changed that I didn't? Bled better?
I'm stuck!

 

[wewfords]

one forum i read said that u have to change the master for 02 brakes b/c the master is differnet due to the bigger brakes than the 93 set up

 

[Mustang5L5]

Unless you change to rear disks, there is no correct mc to use.


With engine off...pump the pedal. Does it get hard as a rock? If so, no air in lines.

How's does the pedal feel when you hit the brakes? Mushy? Soft? Goes to floor?

 

[bdurham]

brakes

Are your drum brakes set right.. If they are too far away from the drums you can't set them. Ben

 

[old_blue]

stock MC is fine with rear discs. I know the bleeder is higher but air can be trapped in there. Try tapping it with the wood end of the hammer while you are bleeding it to see if air comes out. otherwise you'll have to **** it to where the bleeder is the highest point. good luck.

 

[93project]

Thanks guys. I'll get the car back tomorrow and check the air bleed. Again
I thought about using a 95 master. 1-1/8" bore
And ditch the stock proportioning valve for a baer unit. Whaddya think?
As for drums. They're all new and set well. The pedal gets hard when the car is off, and it feels firm at idle. Haven't gotten her out on the road to test. I do hear a normal sounding hiss when I press the pedal at idle. There's good vacuum but that booster is old
Might be the weak link. I'll report tomorrow

 

[Mustang5L5]

1 1/8" master is the 84-86 svo. It's too big.

1995 master cylinder is either 15/16" or 1 1/16". There is also a 1993 conra mc.


Drum brakes require very little fluid to operate. Swapping the front calipers shoudldnt change feel much. The stock mc is 21mm. I'd use the 15/16" mc if I were to change (or 1" 1993 cobra master since it's an easier install) if anything.

Read this post for some more clarification on sizing mc to calipers. Since the drums are staying constant, ignore them and focus on the fromts

http://www.stangnet.com/mustang-for...ke-conversion-upgrade-thread.html#post8075734

 

[Chrome_Rust]

I have the same stuff on the front of my car, and I am running the 95 MC from a V6 car. SVO brakes in the rear is the only difference. But I ditched my factory prop valve, t'd the front brakes together, ran them to the rear port on my MC, t'd the rear together and have a wilwood Prop valve in the rear lineto set the bias, have the rear going to the front port. Car stops, not now, but NOW....

 

[93project]

I have the same stuff on the front of my car, and I am running the 95 MC from a V6 car. SVO brakes in the rear is the only difference. But I ditched my factory prop valve, t'd the front brakes together, ran them to the rear port on my MC, t'd the rear together and have a wilwood Prop valve in the rear linesetupto set the bias, have the rear going to the front port. Car stops, not now, but NOW....

Sounds like a great setup. Do u think I'd need an aftermarket prop valve for the rear since I still have drums? Would u mind sharing pics of your MC line setup? Thanks

 

[Mustang5L5]

I think you guys are missing my point. Disks vs drums on the rear is a huge technical difference. They need to be thought of differently in terms of MC selection.

Front caliper are increased from 5645mm^2 to 6220mm^2 which is in increase of 10% of total system surface area

going to the smallest disk MC (15/16" 94-95 Cobra) is an increase of 28% total surface area. (94-95 gt/v6 MC would result in a 65% larger master piston surface area)

That's why i said there just is no correct MC to use for retaining the rear drums. Rear disks require MUCH more fluid to operate than drums, so installing an "oversized" disk brake MC with drums may result in a stiffer pedal...sometimes not a desireable thing. Sometimes, the stock MC/booster is best when ONLY swapping the front stuff and leaving the rear drums

Swap rear disks on...completely different story. It's a major difference

 

[SMOKEDYA]

What i noticed when i installed my 93 cobra M/C, is that it says to messure the distance of the piston.Then adjust out the rod in the booster.....Maybe you need to check this to be for certian??????peace













john

 

[93project]

5l5, thanks.. makes sense now. No point in putting a larger MC .. maybe adjusting the rod length?

 

[Mustang5L5]

Adjusting the pushrod takes up dead travel. If you have never unbolted the mc from the booster, it's more than likely okay. Adjusting it out will preload the mc and may cause format caliper drag.

Let me ask you this, I know this is a poor test of brake skill, but can you lock the front wheels up?

 

[93project]

Do you mean like hammer the pedal till it locks up and skid? No. It never locks up or makes the nose dive very hard..
It slows down and does dip the front a little but not like true non abs setups. It stops like it has an anti lock setup going haywire. Best way to describe it
i don't know what to do... I have so much to do besides put rear disc that it's far out on the horizon.