Fox T-Bird/Cougar Forums

Technical => Suspension/Steering => Topic started by: BJL on November 01, 2011, 11:34:43 PM

Title: teves to vacuum assist, a few questions.
Post by: BJL on November 01, 2011, 11:34:43 PM
so this is what i have
88 TC
recent sn95 5 lug conversion

i been having issues with the pump and tired of it. i lost abs when i swapped to 5 lug so the teves electro boost isnt needed anymore.

i going to convert to vacuum assist.

the more i read the more confused i get.
i concerned about front/rear bias.
i want a good pedal feel too.

so what i got was 99-04 master cylinder and proportioning valve. plus the lines between the two and some after the valve
also grabbed the twin piston calipers.
i have 94-98 mustang rear calipers and 96 mustang front calipers.
will this combo work with out issues?

i have a 88 sport vacuum booster i can use, but was going to try and get the booster out of the car i got the master and proportioning valve from. its gonna be a lil bit of work since the strut tower is int he way (front end hit 99 mustang in the u-pull-it yard) which is better the 99 stang booster or 88 sport?

anything else i should be aware of?

thanks!
Title: teves to vacuum assist, a few questions.
Post by: Soul on November 02, 2011, 08:35:36 AM
From what I read, I would go with the SVO booster or look at its bore and specs and see which of the two you have is close to it.

This is the article I reference when some one talks about this:

http://www.turbotbird.com/techinfo/Convert_ABS_to_Vacuum.doc
Title: teves to vacuum assist, a few questions.
Post by: cougarman on November 02, 2011, 09:15:58 AM
For what it's worth, we always used the 5.0 Fox Mustang boosters. They are smaller around than the Tbird ones, allowing room for the clutch cable to run. :D

On my Sport I'm using the stock Tbird booster w/ a 1" bore sn95 master cylinder and adjustable porportioning valve.
Title: teves to vacuum assist, a few questions.
Post by: The Shredder on November 02, 2011, 02:33:27 PM
I have a SN95 v6 brake booster, master cylinder and proportioning valve on my TC.  I forget what year (maybe 98). 

I was able to get it to fit without denting the strut tower.  But I had to make sure and drill extra large holes for the booster studs through the firewall.  The sn95 booster is a different bolt patern, so you need to make a template and drill new and enlarge existing holes.

I still have stock TC brakes front and rear, but plan to swap to Cobra 13" front brakes and lincoln rear brakes when I swap to 5 lug.  Right now my brake pedal feel is stock.  I hope to get a stiffer feeling after my brakes swap.
Title: teves to vacuum assist, a few questions.
Post by: Chuck W on November 02, 2011, 03:02:12 PM
The 1-1/8" bore SVO MC would be a bit big. The pedal will be rock hard, with no modulation. Something with a 1" bore would be better, or even a stock SN-95 MC would be a good choice.  I wouldn't mess with the stock prop valve from the Mustang, and just go with an adjustable one.  The balance and weight distribution on your car is not the same as that of a SN-95.

My Scorpio has the same set-up, and when I swapped it to Vette brakes, I kept the rest of the stock plumbing in place.  Even with the front ABS disconnected, the brakes feel great, and the pedal feels awesome every time.  I had to swap out the pump assy a while back (had a spare), but I would probably do the same again if this one fails.
Title: teves to vacuum assist, a few questions.
Post by: thewestie on November 02, 2011, 04:38:57 PM
I used a 87 mustang booster and master with the Tc prop valve and pedal was mushy and faded not sure if it was the set up or a bad rebuild on the master. Redid the set up stayed with the 87 gt booster and used a 93 cobra 15/16 master and a adjustable prop valve and looooove the feel of the brakes firm pedal with little travel and no fade. Cant wait till I put the Cobra 13" brakes on this winter with a little more stoping power.
Good luck
Title: teves to vacuum assist, a few questions.
Post by: The Shredder on November 02, 2011, 04:50:51 PM
The 1998 Mustang has about a 56/44 weight distribution and weighs approx 3,400 lbs depending on the options.  The 1988 Thunderbird Turbo Coupe has about the same weight distribution and weighs 3,400 lbs.  So thats why I stuck with the sn95 proportioning valve.

An adjustable PV gives you more control, but may not be necessary.