General Questions on a 5 Lug Swap -

Car RamRod said:

Ok I recently bought an 89 coupe, 5.0 conversion car. Its not goin on the road for about 2 months. Instead of putting a dime into my current brakes and rear, and buying new tires, Im just gonna do a good 5lug swap. My neighbor has connections with mustang scrap yards. Infact he's scraping a 96 cobra right now, but the rear is already sold. So getting parts isn't a problem. And Ive got a set of wheels I can get real cheap.

What I want to know, is what parts work especially well. Im pretty sure for the rear Im gonna get an sn95 cobra rear bc of the 3:55 gears. But what should I look for for the front? And also, whats intailed in the rear disc conversion from the stock drums? Thanks.

Thanks alot and feel free to share your setups.

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What I have, is spindles from a 96 in the front. They set the front wheels out just a little bit wider than the 94 & 95 units. Some people say the 96+ units lead to rub. I know 96-98 spindles are the same. I don't know about 99 and up. When you use these spindles, you will need to get spacers to go between the shocks and the spindles on either side, as the slot in the spindle is quite a bit larger than the foxbody spindles. You will need washers for the balljoint crown nut if you don't get sn95 balljoints pressed in. Because the spindles are narrower on the bottom, so the crown nut goes quite a bit lower than the hole for the cotter pin on foxbody balljoints. Finally once installed you'll see that the front wheels are toed in now several inches, so you'll need to toe them out alot by eye, just to be able to drive the car, then have an alignment done.. but I'm sure you expected an alignment anyway. Then I've got 99 GT calipers and rotors in the front. I believe on the passenger side you'll find that the foxbody solid brake line nut doesn't fit into the rubber hose for the caliper. You can use an adapter, or cut the end off the line, put the correct fitting on, and re-flare the line. I've done both, they both work. You'll also find the bracket that holds the foxbody rubber line won't hold the new rubber line. You can get a file and re-shape the bracket to make it work, which sucks, I've done that. Or get some zip ties, which doesn't suck, I've done that too

In the rear, for rear disc brakes you need a disc brake backing plate, there's a little support thing with a U bolt that bolts to the plate, and clamps to the axle tube also. AFter that you just put the new 5 lug axle back in, (94-98's work great, don't get 99+'s) slide the rotor over it, and bolt the caliper bracket, or cradle, to the new backing plate. Use a caliper from an 94+ mustang. (v6, v8, cobra, doesn't matter, they're all the same) Finally if you use non-cobra rear discs, you can pull the springs off the stock parking brake lines, unscrew the retaining clips/bracket thingie that hold the cables to the floorpans, and attatch the cables to the calipers. The reason you remove the spring is because the caliper has a spring on it, and it makes installation 10x easier. And you remove the retaining thingie to give you that extra couple inches of slack you'll need. Then screw the clip back in wherever it looks like it should go now... it has a self tapping screw factory.

Finally all this is going to call for a newer bigger master cylinder (I used 86 SVO, but there are MANY choices, do your homework for happyness), and you need to re-work your proportioning valve for the rear disc brakes to work correctly. I suggest gutting the stock valve out completely, and getting an installing an adjustable valve on the passenger side firewall, near the hood hinge. You'll see a factory coupling there that makes install a breeze.

With the smaller wheel wells of the 89 and and the extra track width the 96+ spindles give it probably will rub. Just take the brakes and brackets off and sell the spindles. I got a set of 94 v6 spindles from a junkyard for $100 so they are pretty cheap to get. Rear ends as long as you dont get a 99+ you should be good. Check out this site too ... http://www.svo73mm.cjb.net/

Car RamRod said:

great writeup, thanks alot.

Im just gonna get a new rear all together, with discs already on. With I still need to do all of that modding?
And Im on a tight budget. What kinda master cylinder could I use thats more common than an SVO (I could prob get one from a more common car dirt cheap.)

Thanks again

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Only when it comes to hooking up the parking brake cables. The 98 cobra rear I think has bigger discs on it than the GT does. Although I'm not 100% sure on this. I know that the brakes that came on my 03 cobra rear put the caliper too far away for the stock cables to work. So I had to get some longer ones.

For what it's worth, my 86 mercury has 96 spindles with 255 40 17's on the front with no rub using 94GT 17 inch tribars, or 99GT 17 inch 5 spokes. I don't know if the 89 has a larger or smaller wheel well. However, 5lugfoxfanatic has the same setup on his 86 ford and he says it does rub a little at full lock. I believe he's running a 245 tire.

As far as master cylinder, I got mine from autozone or something. They're really not very expensive. You would have to convert your lines out of the MC from 3 lines down to 2. I did have to get an adaptor fitting for one of the lines however, which I forgot to mention earlier. Your other choices are 93 cobra, 85 lincoln (i think it's the same as SVO but iron instead of aluminum), or any sn95 car. They all have their pro's and con's.

there used to be a handy reference for doing the job at mjbobbitt.home.comcast.net but apparently now the author wants 15 bucks to be able to view those pages

Car RamRod said:

perfect. If its gonna save me money, Im not gonna go with a cobra rear. I can change the gear set, and my cars light so I think a gt's setup would suffice. curious though, what year did gt's go to a disc rear? Im thinkin 95 but im not sure.
thanks

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All mustangs went to rear disc in 94

Dont' forget anti-moan brackets for the rear brakes. Otherwise they'll moan when you're reversing. And it's very annoying

I used 96+ spindles up front. Also have 245/45/17s and no rubbing issues