Brakes The Ultimate 4-lug/5-lug Brake Conversion/upgrade Thread

Discussion in 'Fox 5.0 Mustang Tech' started by Mustang5L5, Nov 28, 2009.

  1. Ah, sorry just saw this.

    Gonna need a calculator...let me get back to you
  2. Also curious
  3. So guys, I came up with this list to upgrade the breaks on my 1990 Mustang. Please can you help if there is something wrong or I am missing something….

    -95 GT parts from junk yard:
    •Spindles and hubs.
    •Axel shafts
    •Rear Brake lines
    •Complete rear brake (rotors , calipers and other hardware)

    -My 1990 stock e-brake.

    -Front COBRA STYLE 13" DISC 94/04 MUSTANG (Mustangs Unlimited - The Premier Source for Mustang, Shelby and Cougar Parts and Accessories )

    -BRAKE MASTER CYLINDER for 93 Cobra (Mustangs Unlimited - The Premier Source for Mustang, Shelby and Cougar Parts and Accessories )

    -Brake booster for 93 Cobra (Mustangs Unlimited - The Premier Source for Mustang, Shelby and Cougar Parts and Accessories )

    -BRAKE ADJUSTABLE PROPORTIONING VALVE (Mustangs Unlimited - The Premier Source for Mustang, Shelby and Cougar Parts and Accessories )

    -BRAKE PROPORTIONING VALVE ELIMINATOR KIT 87/93 (Mustangs Unlimited - The Premier Source for Mustang, Shelby and Cougar Parts and Accessories )
  4. Good luck dealing with mustangs unlimited...
  5. I was quoted less that $50 each for reman Cobra Calipers (wholesale) today from a Ford dealer, is that possible?

    I need to start my upgrade package. Not quite clear on the other stuff yet, Im still learning.
  6. ^^^^ what year? Core required? ^^^^
  7. Any info on Svo rear discs? I got practically everything but it seems no one uses it.. so hard to find info. Just wondering if they are any good or no or should I sell and get something else?
  8. What's your front setup?

    They are heavy and parts tend to be a bit more costly than sn95 stuff.

    There is a way to modify them to rub stock fox length 5-lug axles.

    Seems the site is down now. Perhaps an Internet back history search on the page might work

    Sent from my iPhone 4S using Tapatalk
  9. Ill be running 04 Cobras up front. I have everything needed for the rear I think, will need to buy pads but that's it. Got the brackets, calipers, lines, e brake cable, rotors, and a Svo master as well. Also have the 5 lug axle shafts as well as the whole svo rear end if I wanted it. I plan on just swapping everything to a stock fox 8.8 that has 3.73 in it.
  10. I converted my '88 LX as follows:
    A '95 Cobra donated front rotors, calipers, hub & spindles, rear axle complete.
    Also purchased: New 1" bore M/C (93 Cobra), Wilwood prop valve, set of steel '95 Cobra flex lines for the rear calipers, set of '87-93 steel flex lines, MM "prop valve eliminator kit" MMBAK-6, the 3-2 port conversion MMBAK-3, and a pair on new brake hardlines for the rear axle.

    I made the .330 tall spacers for the front hubs to Fox ball joints. Bolted up the new stuff, and used the Fox flex lines. They attached to the Cobra calibers with the bolts that came with the calipers with no issues at all. I'm considering some type of tie-back on the driver's side, as they will lightly rub the tire on a hard left turn, but they're Russel, so they're pretty tough.

    I used the stock '88 booster. The '93 Cobra M/C bolted right up. No slotting any holes, no blacksmithing the shock tower. (The '93 Cobra M/C seemed the best compromise for my application. One thing to consider in the brake discussion is overall vehicle weight. Foxes are a few hundred lighter than SN's on average. Besides someone beat me to the one in the donor car.) I pulled the factory prop valve off, connected the 3-2 conversion kit directly to the lines that formerly connected to the bottom of it, and moved on to the rear.

    I took the stock '95 axle hard lines, cut the flare off at the "tee" end as short as I could, slipped on a compatible fitting for the Fox body tee, and re-flared them. I used new '95 stainless flex lines on the wheel ends and bolted them up to the Cobra calipers. One of the brake tubing companies makes the hard lines already done. Classic Tube maybe? I found this out AFTER I borrowed, broke, and replaced a friend's double flare set.

    Being both lazy AND cheap, I was not about to fork over $2600 for the K kit, nor was I going to spend a month of weekends pulling crap off in junkyards. I bought the totaled donor, stripped what I wanted in the comfort of my own driveway (WITH air power), and parted out the rest. I actually made money on the car! Yes, I got lucky that it WAS a Cobra, but you could do the same with ANY '94-'99 Mustang. There are no adapters, cut/welded/machined/modified/redneck engineered parts in the system. I am still experimenting with front/rear proportioning, and will consider pad and rotor upgrades as things wear out. As of now when I stomp the pedal the car stops N-O-W.

    Pictures or further details on request.
  11. That's the portion I always wondered about. I hear mixed reviews with the OEM booster and I LOATH the thought of having to beat on towers etc. So brakes work well for you? No spongy feel or hard pedal?

    ...and by all means... post the pics!
  12. Modulation is as good as stock. But bringing the car down from double digits is a real hoot! Pedal travel is acceptable from light to max pressure. I think the fact that there are no rubber lines anythere in the system firms up the pedal considerably. I just realized I don't really have any pix of the front brakes. I'll get some in the next day or 2. In fact, this shot of the rear was back over the winter. LOTS of parts have been added since. View attachment 72252
  13. Took me a while to get around to the pix...
    Here's the RF corner. Fox flex lines with bolts that came with the calipers. RF Corner.JPG
    This is the body-to-axle flex. Fox part. Rear brake line.JPG
    Underhood shows manual prop valve in typical spot. July 2012 engine bay.jpg
    Noobz347 likes this.
  14. OldbutNew

    Just saw your update to this thread. Very nice. :nice:

    Thought about doing your own build thread with all the step by step and pics?
  15. Can 07 wheels be used with 94,95 spindles.
  16. im using 91 v8 fox brakes on my 86 4 cyl. what hydro boost and mc should i run?
  17. I've been reading and I'm confused. I want to install the sn95 front spindles and rear axles 5lug disk all around
    Which wheels will work with this set up on a 1990 vert.?
    Does this wheel work on all 4 corners: 17X9 backspace: 6" Offset: 25mm deep dish
    245/45/17 front 265/45/17 or 245/45/17 rear

    see link:

  18. The old K kit called for 17's with a 5.75 backspacing. The 6" would probably be good if you use SN-length rear axles. I would bet you'll need to roll the lips to clear those tires. If you are lowered, even more so. If you use a Fox-length axle, the 6" offset with those tires will probably rub on the inside. I used SN length axles with the 17x8's and 245/45's. No rubbing anywhere.
    In the fronts, it could be a bit close to the strut, but you would have to put them on and check ALL the clearances to be sure. I put a pair of steering rack limiters on mine, and my wheels are 17x8 with 5.75 backspacing. I'm running Eibach Sportlines, so the car is pretty low. Those wheels a er sharp! I hope you make them work.
  19. Can anyone identify which setup is on mine as I have no idea. Wheels are 17 x 9 with 245/45 tires. Sorry about lousy pic, it's been raining all day. If a better one is needed I'll try again in the am. There is a 1/4 spacer on rotor, haven't measured the wheel offset yet. Even with the spacer wheel rubs control arms on hard turns slightly. Trying to figure what I'm working with prior to replacing anything or new brakes, wheels etc.
    View attachment 133443