Wheels-Tires Need Some Help - Brakes Upgrade/Wheel fitment

[jaygee15]

I am still very new to Fox body cars/mustangs in general. I have an 86 Mustang that I am building. Its a 6 cylinder car that I will be doing drivetrain swap, suspension, brakes , basically everything. This is a budget build compared to other cars I've built.

My question is in regards to Brake and wheel fitment. I've read this thread https://stangnet.com/mustang-forums...5-lug-brake-conversion-upgrade-thread.801400/

along with others regarding doing a 5 lug swap and am looking at doing the cadillac ats brembo brake swap/upgrade, as its seems to be a great option for a tight budget and still getting a good setup for brakes. I am looking to figure out what wheels will fit. One of the wheels I want is the Saleen SC style wheels in 18 inch, would these fit without a spacer, or with no more than 1/4" spacer? I dont want to put a big spacer on the car. If they wont, what all wheels have people fit on this setup. Any links to threads or info is appreciated.

thank you.

 

[86HO5.0]

The stock 86' K-member is .5" narrower on each side vs 87-93 K-member. SN-95 front LCA's and S197 wheels (45mm offset) fit great on these cars and will allow more clearance when turning due to the ball joint being closer to the center of the wheel.

I'm running a complete 94-98 Cobra brake setup with the 94-98 M/C and stock 86 booster, pedal feel and modulation is excellent. SN-95 front LCA's, SN-95 length rear axles and 17x8 S197 wheels. No spacers needed up front, running 1/4" spacers in the rear to improve stance/looks. Front stance is stellar, turned out amazing. 245/45-17's on the front and I can turn lock to lock w/o any rubbing.

Hope this helps. It's proven setup that works amazing.

 

[AeroCoupe]

I will tell you that going to the larger front diameter brakes looks great behind the wheel but I noticed very little between the SN95 V6/GT front brakes with 99-04 calipers vs the current Cobra setup I have on my Coupe. If you want to do this on a budget and you are not going to road race the car the larger front brakes are just bling. Don't get me wrong it looks cool and all but you are spending a lot more money for not much more brake performance on the street.

If you want better braking spend your money on an ABS system because that does make a difference in hard braking. I put a 1995 GT system on my Coupe and that was worth the money.

 

[jaygee15]

I will tell you that going to the larger front diameter brakes looks great behind the wheel but I noticed very little between the SN95 V6/GT front brakes with 99-04 calipers vs the current Cobra setup I have on my Coupe. If you want to do this on a budget and you are not going to road race the car the larger front brakes are just bling. Don't get me wrong it looks cool and all but you are spending a lot more money for not much more brake performance on the street.

If you want better braking spend your money on an ABS system because that does make a difference in hard braking. I put a 1995 GT system on my Coupe and that was worth the money.

So would the sn95 calipers/spindles/rotors be my cheapest option for an upgrade? Compared to the cadillac ats setup. And the sn95 will have much better wheel fitment options.?

 

[86HO5.0]

You're going to need SN95 spindles/rotors regardless IMO. One nice about utilizing OE style calipers is the ability to run a OE style M/C, there's no guess work regarding pedal travel or feel. Stock SN95 cobra M/C's are very close to the same size as a fox M/C so retaining the stock booster isn't an issue.

Here's a good thread on ATS vs Cobra brakes.

https://www.corral.net/threads/cost-of-foxbody-swap-to-ats-brakes-vs-03-04-cobra-brakes.2515090/

EDIT--Just did a quick search on cost difference of rotors and calipers for Cobra vs SN95 with PBR's. Cobra front setup will cost about $100-150 more.

 

[jaygee15]

You're going to need SN95 spindles/rotors regardless IMO. One nice about utilizing OE style calipers is the ability to run a OE style M/C, there's no guess work regarding pedal travel or feel. Stock SN95 cobra M/C's are very close to the same size as a fox M/C so retaining the stock booster isn't an issue.

Here's a good thread on ATS vs Cobra brakes.

https://www.corral.net/threads/cost-of-foxbody-swap-to-ats-brakes-vs-03-04-cobra-brakes.2515090/

thank you. Yes I am planning on the spindles already as I am doing 5 lug swap as well. So it would probably be the cheapest, easiest route to just go sn95 everything, including rear end, rear brake setup, front spindles, calipers, rotors, mc and bb? Thanks for the link as well.

 

[86HO5.0]

IMO--Go SN95 with almost everything. Use the stock Fox booster if utilizing 2 piston calipers up front. (94-98 are 38mm, 99-04 are 40.5mm).

You can using the stock fox rear housing and just upgrade the brakes. A different caliper bracket will be needed if using Fox length axles.

Buy some MM caster camber plates as well, you'll need em.

 

[jaygee15]

IMO--Go SN95 with almost everything. Use the stock Fox booster if utilizing 2 piston calipers up front. (94-98 are 38mm, 99-04 are 40.5mm).

You can using the stock fox rear housing and just upgrade the brakes. A different caliper bracket will be needed if using Fox length axles.

Buy some MM caster camber plates as well, you'll need em.

I have a 6 cylinder car so need to upgrade to the 8.8 is why i mentioned doing the whole rear end.

 

[86HO5.0]

If you buy a 94-98 rear axle assembly, you can use it as is w/o swapping caliper brackets. SN95 front LCA's will match up nicely.

 

[jaygee15]

So If I bought a 94-98 donor car, I could pull all this from it, and as you mentioned including the front lowers which will help with steering.

 

[86HO5.0]

Yes, if it was a Cobra. 94-98 GT's come with different calipers than the Cobra's, these have more displacement and a larger M/C which will require a booster swap.

If you buy a donor car, use the steering rack as well. Much better steering feel.

 

[jaygee15]

ok so it has to be a cobra, or I will have to swap booster as well.

 

[86HO5.0]

Yessir. Cobra or PBR calipers require less fluid and a smaller M/C than the stock 94-98 front calipers.

 

[86HO5.0]

Another alternative would be a 99-04 GT as those came with PBR's on the front, the pistons are larger than what the Cobras use. The rear axle housing is 1.5" wider on these cars vs 94-98.

EDIT: DO NOT run 96-04 Spindles on a Fox.

 

[jaygee15]

thank you for the help

 

[AeroCoupe]

So if you are keeping the stock k-member you should try and get the 94-95 spindles. I ran the 96+ spindles with a stock k-member and just used a tapered bump steer kit and it was fine but everyone (including Maximum Motorsports) says the 94-95 are what you should run with a stock k-member.

If you have a 7.5 rear end and want to move up to an 8.8 then get the complete rear end out of a 94-98 GT. I would encourage you to replace the rear calipers, pads and rotors as well as service the rear end with a traclok clutch kit and new fluids. You may want to chang the axle bearings and seals while you have it torn down but that's up to you. This rear end will bolt into your car with the exception of the brake line connection. I would buy this:

https://lmr.com/item/LRS-2073BRKT/mustang-v8-rear-upper-brake-hose-bracket-86-93

Modify the brake line on the car to get to the fitting above and then use the brake lines on the existing rear end.

As for the front brakes you will need the front spindles, hubs, rotors, and calipers. If you install the spindles on stock Fox ball joints you will need 0.330" of washers or shims between the top of the spindle and the castle nut so the cotter pin will lock in the castle nut. If you are going to rebuild the stock control arms or buy new ones look at installing the low friction SN95 ball joints in the Fox control arms.

Low-Friction Ball Joint, 1979-2004 Mustang

You will not need any shims with these ball joints.

Check the hubs and if they roll freely then just reuse them. IF not then get new ones but be weary of what brand you buy. I will only use the Timken, BCA, or Motorcrafts. Replace the rotors and use the existing calipers as your cores for rebuild 99-04 calipers. I would either replace the rubber lines from the hard lines on the body over to the calipers with rubber or if you feel the need go braided stainless steel. You may or may not need the adapter for the passenger side soft line so if you do it is a Weatherhead 7828.

Your car was already a two line car at the master cylinder so a Cobra master cylinder will work just fine. The issue will be that your car has SAE fittings and the Cobra MC has metric. This kit may work but your car is a V6 and not a V8 so I am not 100%:

Master Cylinder Installation Kit, 1994-95 Cobra master cylinder in 1980-86 Mustang

The other thing you should do is gut the combination valve on the proportioning side and add a manual proportioning valve. Here is a cutaway of the combination valve:

You need to remove the plug on the left side to gain access to #5 and remove it. Use this plug in place of the one you removed:

Mustang Brake Proportioning Valve Plug M-2450-A - LMR

Plug your factory proportioning valve with this 5.0 Resto direct fit Mustang Rear Disc Conversion Proportioning Valve Plug!

lmr.com

And here is the manual proportioning valve you need:

https://lmr.com/item/M2328C/Mustang-Ford-Racing-Adjustable-Brake-Proportioning-Valve?utm_source=google&utm_medium=cpc&gad_source=1&gad_campaignid=20122150522&gclid=EAIaIQobChMI34Wr47C2kQMVTl1_AB20LTNgEAQYASABEgI8VvD_BwE

Here is the location of the manual proportioning valve that most people use:

I would also stronly suggest you get a 1993 Cobra booster as it is identical to the SN95 booster but it has the Fox firewall bolt pattern. The SN95 system was designed with this booster and I have it on both of my cars and can tell you that there is a difference between it and the Fox booster.

Mustang Power Brake Booster (1993) Cobra - LMR.com

1993 Cobra power brake booster will restore the proper function of your Mustang power brake booster!

lmr.com

All of the links to buy stuff are just so you get the idea. Shop the parts and you will most likely save money. For the used parts a good place is www.car-part.com or your local salvage yard.

 

[jaygee15]

.

Awesome write up of info. Thank you for it all. I do have a question, right now the car runs and drives although I rarely drive it as its a project and am saving to make moves on it. Recently I went to take it for a spin and have no brakes(pedal to floor) I found no leaks and suspect mc or bb is seized. Would I be able to do a portion of this brake upgrade/swap so I am not spending money twice on brakes. Rather than getting the stock mc or bb , whichever is bad, replacing it or both with the sn95/cobra stuff but keeping everything else(lines, calipers, etc) stock for now.

 

[AeroCoupe]

You are probably looking at a failed MC but it could be the booster or both. I would try to bleed the brakes and if that fails then go ahead and install the Cobra booster and MC. You will need the tubing kit so the brake fittings are the right thread on the MC. If you can swing it gut the combination valve and install the manual proportioning valve.

 

[jaygee15]

You are probably looking at a failed MC but it could be the booster or both. I would try to bleed the brakes and if that fails then go ahead and install the Cobra booster and MC. You will need the tubing kit so the brake fittings are the right thread on the MC. If you can swing it gut the combination valve and install the manual proportioning valve.

Does this look correct? Besides some of the small stuff mentioned.

94-95 spindles(f5 on back)
Sn95 hubs, front lca, brackets, steering rack, master cylinder
pbr caliper and rotor
93 cobra booster
94-98 rear end
Ford Performance or Willwood adjustable manual proportioning valve

 

[AeroCoupe]

Rear end has to be out of a GT. V6 cars have a 7.5 ring gear. Axles out on the 7.5 and 8.8 are identical but the ring gear size are different which means the gear area of the housings are different. If you cannot locate a complete 94-98 8.8 rear end then you can use a Fox 8.8 and use the axles out on a 94-98 V6 rear end.

You want the front calipers off of a 99-04 GT or V6 to get the twin 44mm piston design. I forgot to mention with the 94-95 spindles you will need to clearance them but it’s zero work with a 4” grinder and 80 grit flapper wheel or a little elbow grease with a coarse hand file. You will immediately see where when you bolt the caliper up on the spindle. 96-04 spindles do not need this modification. Here is a a picture of the modification looking down on the spindle.

I think it’s a little overboard but they were cast so the tolerances are not like a billet piece.

Why do you want the SN95 lower control arm up front? This will push the wheel outward and pretty much limit you to a 8" wide wheel. If you reuse your stock control arms and rebuild them you can get a 9" wide wheel up there pretty easily. You will need rack limiters so the inside of the wheel does not rub the subframe but other than that it works really well.

Rotors can come off a 94-98 GT or V6 car.