New 4 Wheel Disc Brake Setup

[beartooth]

Hi all, I've been lurking here for a while and this is my first posting of many that I hope to share as I begin my restoration (RestoMod) of my 84 Avanti I acquired back in May of this year.  I have just begun to work on it as I had many summer projects around the house I promised to get done before I touched the car 😂.   So my first project was to modernize the brakes and much to my surprise the front disc brakes are actually from an 84 Z28 Camaro thanks to the help of Mark Ritteringer over on the Facebook group. I'm just not a fan of the integrated hub and rotor setup along with the spacer and bolt pattern adapter that was used on the frontend.  I saw some older post using some Ford disc brakes and thought that was a good start.

Here's what I came up with, I have a good friend that owns a "Mustang" performance shop and they regularly change out the brakes and scrap the old stuff.  I obtained a complete set of 2004 Mustang GT calipers and rotors from a car that basically had 9K miles on it but had setup for 10+ years.  Here's what they looked like.

I completely took them apart, cleaned them, ordered all new hardware and rebuild kits and prepped them for painting.

Seeing how I didn't have original Avanti Hubs, I researched a ton of hours and came up using some Wilwood hubs.  Here's a drawing of how it all fits.

I have this in PDF and DXF format if anyone would like this.  In fact this entire setup I hope to document will be "opened sourced" to anyone interested as long as you use it for your personnel use and not for sale.

I did all my proto typing with plywood to make brackets.  I have in my shop a 4'x8' CNC router, 4'x8' CNC plasma table and a CNC laser and other wood and metal machines/tools so I was able to make everything.

For the Wilwood Hub I had to mill outer diameter down to allow the rotor to fit over it.  Turning it down would have been a bit of a challenge as there's not much to grip on for a lathe, so I opted to clamp it down onto my CNC router table and mill it.  I don't have a lathe but I have access to one at a local auto machine shop.

Note: I used the 3/16" spacer that was originally in the integrated Camaro hub to space out the inner bearing. 

Plasma cut brackets out of 3/8" steel plate, the holes were all spot pecked on the plasma and final center drilling and drilling were completed on the drill press, the rear brackets have a stand off spacer welded on to get the caliper centered correctly.  I'll explain the rear setup in a bit.

Final assembly, one note here it's a little hard to see but I used 3 thin bushings between the studs and rotor bolt holes as the rotors hole were larger than the 1/2" Wilwood studs and they don't have any shoulders.

For the rear, my axle tube ends have 6 bolts, I've seen others say they only had 4 and my axels are not tapered ends with a hub.  So this is where things get a little different through the years and even a year of production I'm guessing.  When you eliminate the backing plate on a Dana 44 rear end you have to have a spacer to fill that missing drum backing plate.  I found the backing plate is a little odd thickness, a little thicker than 10ga, so I made this plate and lasered a gasket to make up the difference.

Also, I had to have the axle flanges turned down and 3/16" to a 1/4" (can't remember the original diameter) to let the rotor to fit over it.  The studs have a rather long and large shoulder and I needed to drill the rotors to 5/8". 

Final assembly of the rear.  The nice thing about the Ford rear calipers is the emergency brakes will work with a pull cable setup and are return spring loaded.  You can use a universal e-brake kit from Wilwood or Summit.  I have all new stainless braided brake hoses as well now.

 

The next part some people will cringe but here it goes, wheels and tires...  Getting wheels with back spacing/offsets that will work for an Avanti is some what of a challenge.  As luck would have it, my brother lives about 2.5 miles away and he has a 67 RS/SS Camaro and he recently put on some nice Boze Flow-Forged wheels and I was able to mock the front up due to the fact that the Wilwood hubs are made with both the Ford and Chevy bolt pattern.  So we mocked up the front like this.

Made sure I had clearance all around, wheel lock to wheel lock, these are 18"-8" wide wheels with 245/40 tires.  Had miles of room!  I went slightly different as a) I didn't want to copy my brothers setup entirely and b) if we went to a car show together and were side by side it would look to obviously they were the same. 

Originally, my car had 15" wire wheels with 205/65 in the front and 225/70 in the rear.  Here's the original rear and the tire was clearly outside the fender.

I went with a different style Boze wheels, 18"-8" 235/40 on the front and 18"-9.5 275/40 in the rear, Nitto NT555 G2 tires.  We wheeled her out in the sun and my brother took a few pictures for me.  I'm going to work on the stance a bit, not much though, remove the front spacer inthe front coils that the factory put in and lower the rear a tad.

The rear wheels are actually slightly less sticking out of the fender wells than originally!

I do have all the bracket's in DXF format so if anyone is interested in them just let me know.  Once I get the stance were I want it, next up is removing the engine and transmission.  I'm going to rent a "hotsy" (steam) pressure washer and clean the entire under carriage, engine bay, rebuild the front and rear end, paint and detail the bottom of the car, lots of fun and more mods to come!

Kim