4cyl LX to GT Brakes

[marine_2003]

I need to change my brake set up from LX 4cyl Brakes to GT brakes, the guy i bought the car from did the 4 cyl swap and left the 4 cyl brakes, it has hardly any stopping power. Do I need to change spindles and everything?? Also do I need to change the rear brakes??

 

[bullitstang1313]

Yes, the spindles are different. The bigger GT rotors and calipers will not bolt up to the 4 cylinder spindles. I believe the rear brakes are the same as the 5.0's though.

 

[mattmcdan]

Im in the same boat, let me know how it turns out.

P.S. Thanks for the T5 trans, I'm about to put it to use.

 

[thehueypilot]

Yes, the spindles are different. The bigger GT rotors and calipers will not bolt up to the 4 cylinder spindles. I believe the rear brakes are the same as the 5.0's though.

The spindles are thicker where the struts bolt to as compared to the GT. I found this out when I tried to install adjustable struts (Strange Engineering)onto the 4 cylinder brakes and it would not fit. The solution was to mill down the pad on the spindle and they work fine now. I still run the 4 cylinder front brakes but with the 93 Cobra MC/PB and Explorer rear discs and it works well but I only drag race with it.

 

[marine_2003]

I talked to one of my long time friends Tim that works at my local speed shop American Motorsports and he said that the spindles are the same on the 89's whether they are 4 cyl or not. I guess that they went to the thicker spindles then. The GT stuff should work. I trust this guy, he has been building Mustangs and been around alot of Ford Cars all his life. I will be starting to collect my parts and keep everyone informed. If anyone want to call Tim to confirm his number is (407) 290-6565. They are open from 9-6 M-F and 9-3 Sat
http://www.americanmotorsports.net/

 

[bullitstang1313]

My vehicle is 88 4cylinder LX and the donor car was an 88 GT. The spindles were different for me. The GT has larger calipers which did not fit the 4 cylinder spindles.

 

[MrKwik]

I talked to one of my long time friends Tim that works at my local speed shop American Motorsports and he said that the spindles are the same on the 89's whether they are 4 cyl or not. I guess that they went to the thicker spindles then. The GT stuff should work. I trust this guy, he has been building Mustangs and been around alot of Ford Cars all his life. I will be starting to collect my parts and keep everyone informed. If anyone want to call Tim to confirm his number is (407) 290-6565. They are open from 9-6 M-F and 9-3 Sat
http://www.americanmotorsports.net/

Your freind is wrong....sorry. On earlier cars, the 4 and 8 cyl were all 10" rotors. I'm wanting to say it was 82-86 but may have been 83, not positive. Before that, there were even smaller 9" front rotors on 4cyl cars. From 87-93, 4 cyl cars still used the same 10" rotors as the earlier cars but V8 cars (GT or not) got 11" brakes. The spindles ARE different between the 4cyl and V8 cars and you can not bolt the bigger rotors on the 4cyl spindles, and even if you could the caliper would adviously be in the wrong place. The "thicker" part poeple are talking about is just where the strut bolts to the spindle. If you have ever bought auto parts store replacement struts for a V8 car, you will find that that area is wider than your spindle but they come with some spacer plates. I have accomplished the same thing in a pinch with washers and never had an issue. The top mounting hole in the strut is also slightly elongated because the spaceing between the 2 different spindles is slightly different.

In most cases I believe you can just swap the complete spindle assembly and attach the V8 rubber hoses to the factory hard line. I have found that earlier cars use a smaller fitting on the hard line so you have to replace it with a larger end and replare it.

 

[Mustang5L5]

I talked to one of my long time friends Tim that works at my local speed shop American Motorsports and he said that the spindles are the same on the 89's whether they are 4 cyl or not. I guess that they went to the thicker spindles then. The GT stuff should work./[/url]

He is wrong, sorry.

The 4 cyl uses a 10" rotor while the GT uses a 10.8" rotor. As a result, the mounting points for the caliper are in different locations.

To do the swap, you need spindles, rotors, calipers, brake lines.

You should also change the brake booster. The 5.0's use a dual diaphram booster while the 4-bangers and the 79-86 Mustangs use a single diaphram. The dual booster offers more power.

I would swap the prop valve and MC on from a 5.0 as well

 

[RBRANDX]

If you are interested I have everything you would need to do this sitting in my garage...make me an offer!