Checklist for 2.3 to 5.0 front disk swap.

if you want to swap to the 87-93 5.0 brakes, and you have the smaller 10" 2.3 brakes (79-86 have the same ones regardless of engine size...) you'll have to get the 87-93 5.0 spindles as well, and with that, you'll have to get the same model struts, as the 2.3's and 5.0's have different mounting width at the spindle(found this out the hard way)

the caliper mounts on the spindle are specific to the disc diameter, so you can't just swap to the bigger disc without swapping the spindle and caliper as well.

another common upgrade when doing that is to swap out the stock caliper with the SVO/MK7 73mm calipers, which are readily available at your local parts stores (plus core charge), they have a bigger piston than the stock 5.0 and thus increase clamping force, and they fit the stock 11" 5.0 rotor.

spindles from an 87-93 5.0 should be available at a local salvage yard for no more than $30-$40 for the pair, you can also find them on ebay...I also have a set laying around with good rotors, calipers, pads, and lines if you're interested.

edit: ok, i lied i just looked at the parts, i don't have the lines, but they are availabe at the parts store, or you can buy stainless flex hoses..

good luck with the swap!

you'll also need brake hoses and the banjo bolts as well.you'll also need an alignment as the spindles have a different track width and stut mounting angle as well.my 88 was also an original 4 banger that i changed over to v-8 brakes.even the wheel bearings are different as is the dust shield so try to get the dust shield with the spindles.

When I did the swap. I used 5 lug Ranger front rotors and Ranger Axles. Then I switched to Strange 31 spline axles.

I have also heard in addition to the brake hoses that you need the proportioning valve and master cylinder too.

I'm all about upgrading for increased braking but if you are going to upgrade the brake system the stock fox brakes aren't that good. You can swap to 94-95 spindles and get much better SN95 brakes for just a few dollars more and the same amount of time and aggravation.

yes, stock fox brakes leave much to be desired, but an 11" rotor up front is still an improvement from the stock little 10" that he was using, but if you install the bigger calipers, then it's even more an improvement. and for most people-unless you're running road courses or autocross, then well maintained, fox brakes will suffice-especially with some good pads

the whole reason for gutting the stock proportioning valve is for the rear brakes...and there's bound to be several people on here who have swapped to the lincoln 73mm calipers up front with no other modifications.

now, whenever he does the back brakes, then yes, it will become more important (read: imperative) to gut the stock valve, and install an adjustable for the rears.

add'l info: the 11" rotors w/ 73mm calipers are what SVO's came with from the factory...seemed to work pretty well for them

Let me see if I have this right. There are 2 options.

1 You can use an adjustable proportioning valve. I would imagine that it would be best to remove the stock spring (for the rear) from the distribution block when doing this.

2 What I did was pulled a spring from a car that had rear discs and istalled that in my distribution block. This has worked very well for me, and was less expensive than the aftermarket proportioning valve.

Are there any other ways to compensate for rear discs?

Mustang5L5 said:

There is really only 1 option. Option #1.

Your car didn't come with rear disks, so using the spring from another car would still not be correct. It's not set up for the weight distribution and braking characteristics of your car. SN95's have more weight over the rear tires than a fox, so they will apply more rear pressure...which could be problematic.

#2 may work, but could also cause a big problem

Click to expand...

agreed

it may work, but I'd rather pay the $40 for a Jegs moniker p/v and $9 for the p/v plug from FRPP...good piece of mind IMO

Mustang5L5 said:

There is really only 1 option. Option #1.

Your car didn't come with rear disks, so using the spring from another car would still not be correct. It's not set up for the weight distribution and braking characteristics of your car. SN95's have more weight over the rear tires than a fox, so they will apply more rear pressure...which could be problematic.

#2 may work, but could also cause a big problem

Click to expand...

Manual GT Hatch
FR 1849 RR 1342 57.9%/42.1%

1994 GT
FR 1927 RR 1453 57.0%/43.0%

Although the rear weight does differ by 111lbs you are still looking at only a .9% difference in proportionate weight. Seems pretty insignificant to me.

I will even go as far to say that I would be surprised if most people could tune the rear brakes within 1% of ideal, with a proportioning valve. I can actually mess your brakes up more by sitting my 220lbs in the back seat.

That's just how I look at it