1968 Mustang Fastback - Pro Touring - 4.3 SVT Cobra

This project is going to be a full on custom combining the body of a 1968 Mustang Fastback and the workings of a 2003 SVT Cobra into one very cool project. The basics of the build will include:
2003 SVT 4.3 Ford Modular Motor w/Whipple Charger - 750 rwhp
Modified Manual 5 speed
Rear Independent Suspension
Hybrid Ford/Fatman Front Suspension
Wilwood - 6 piston 14" front brakes & 4 piston 13' rear brakes
Retain and utilize all Ford SVT ABS & Traction Control Systems

The Fastback we found from a long time Mustang guy up in Brighton, Rod Holland with American Stang. He has been working on Mustangs since the early '80's. This was one he refurbished the body, frame and floors in. The best part is he has a "Frame Jig" that he purchased from Carroll Shelby way back when, that holds the car in true alignment while he replaced the rear quarters, roof, floors, and one rusty rear frame rail. 
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The donor car is a wrecked 29k miles 2003 SVT Cobra we found on Coparts. Our buddy Georgi , of Gerogi's Auto Sales in Denver out bid everyone else and secured it for us. Thanks Gerogi !!!!     Other than being slightly wrecked and dusty, it was in very good condition, obviously someone's baby. 

Got the '68 Mustang into the shop. First order was to get it fit onto the rotisserie. 

Parting out the donor Cobra. Since the car was wrecked, unibody bent, I just took the sawzall to the front and made life a little easier to ge the motor and trans out. Used the dolly we got with the Mustang body to hold the motor. Sometimes things just work out.  

The Fastback came with an old style mustang II front suspension the American Stang Crew installed. Let's just say it was anything but a clean and quality install. Booger welds and scabbed on parts. Plus these style of front ends are outdated and not strong enough for our build.

The car had new floor pans installed before we purchased it, which was good, but all the old areas under the car had been covered in a coat of paint, by covered I mean they cover all kinds of old junk, undercoating, and rust. Not good. So hired Blake to come out and hydo-blast the bottom. Fast and easy. Now I have a clean surface to weld to.

After the blasting we could see all the liberal use of seam sealer to conceal so poor installation of the new floor pans. I had to use a torch and wire brush to remove all this ugliness.  I did not photgraph all the repairs, but I did go through and tighten it all up and thoroughly weld all the joints.

Time for some fun stuff. Subframe connectors made from 2 1/2" square tube steel. I cut a slot in the floor to connect the front and rear frame rails, plus it strengthens up the floor and whole car.  Did one at a time so the car did not move at all while on the rotisserie.

Nice and tight. The sub frame in seen in the rear seat floor, which is not always desirable, but since we are eliminating the rear seat, it is not and issue for this build. I molded in the connectors where they tied into the frame on the front and rear. 

Fitting the rear IRS form the SVT Cobra into the project. The client purchased a 
"IRS for Vintage Mustangs Kit" to accomplish this from "Dave Stribling Restorations". We were both a little disappointing in the kit after getting it. Kind of amateurish bolt on thing, over priced for sure. The sad part was the client purchased a "drop cradle kit" that was supposed to move the IRS 2" further up into the car, thus lower the car 2", but Stribling failed to inform him that the kit was we were to send him the bare subframe and he would modify the subframe. This process we were to allow up the 8 weeks for.  Yea right. 

No way we were going down that road, so got that money back and proceeded with my own plan. The bolt on program was out, weak and inaccurate, weld on was my plan. I welded on some temporary struts on the subframe with 2" spacers on the car. So after cutting the subframe and removing the spacers the subframe would drop down to the correct height. Then I could pull measurements from my reference points on the front of the car to square things up, level things, plumb bob the wheel openings, and so on.

**Just a quick note, I love doing this work with the car upside down. Easier to use a lift to move stuff, clear area to work, easier to measure, and I don't have to crawl around on the floor. 

After the subframe was cut and dropped, correctly positioned, I just welded it back together in it's new place. Got ride of some of the bolt up bracketry and re-positioned the brackets, welded and braced them as I saw fit. Way stronger and nicer. When the IRS comes off the car to be painted and refurbished I will finish the welding and make it all pretty.

We will be pushing 800hp through 14" tires, so no weak ass BS on this build!!

The front suspension will be a "Heidts Pro G".  The kit is nice and beefy. We got the kit minus the coil overs, steering rack, and brakes. You'll see our upgrades later. This is the stock unit resting on our stock frame. 

The stock Heidts track width was 3 1/2" too narrow for our build, wanted to match rear IRS so I widened the cross member. I added some tube steel to the outside on the stock Ford frame rails and then notched the old frame rails. I also added some bracing from the frame rails to the torque boxes to help with strength, twisting, and rigidity. 

Now that suspension is established I started on the roll cage. I try real hard to keep my cages tight and flow with the lines of the car and the interior. This is more of a street car than full on race car. The cage will provide safety and rigidity to the unibody. 

These are my bending tools, a draw bender I built with plans from the die company, an old kink-o-matic i use for small adjustments, a tube notcher, and a roll bender I made as a proto type. The roll bender gives me the nice smooth bends. Lot of human muscle to roll the tube back and forth to get a nice bend, but worth it. 

Here is a shot of the drivers bar on the bench and installed. Tricky to make all the bends work just right.

I have attached the cage to the uni body in as many places as I can, sides, roof, ect, so it works together with the uni body.

The top of the front shock/spring will be mounted to the hoop over the cross member. The bar going back into the firewall attaches to the roll cage for support and twisting.  

"For this project we are using "Air Lift Performance" units with active ride height control. Since they do not make a kit for either the SVT Cobra IRS or the Heidts Pro-G, so we had to pick a kit we could modify to work with out setup. We picked the kit for the "Audi R8" as it seemed to be the only kit that was not based on a front strut suspension. The R8 had a similar weight to our project too.  We opted for two sets of rear shocks as they have 1/2" more travel than the fronts. 

These units have 30 clicks of rebound and compression adjustment, as well as "active ride height control". Have height sensors to install at some point. The whole system will be controlled via a tablet in the dash. I built some "mock up" struts to use when I build the mounting points and work on the usable travel. As it turns out the difficult part of the install is, the top and bottom mounts do not have much movement, so end of these mounts has to be parallel to the pivot of the lower control arm, no twisting or turning.