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1970 Mustang Fastback Boss 302 Tribute Coyote Restomod Build

96K views 509 replies 60 participants last post by  Boss5Oh 
#1 · (Edited)
Well after lurking here reading the build threads of others, it is time I stop procrastinating and get my build thread going.

This is going to be a long term project, likely 3 years or more, ideally will be done in 2021 or sooner. The build started with a mostly rust free two owner California car. Although I was not specifically after a Mach 1, I was after a 1970 fastback. The end product will be a Boss 302 tribute car, however the 302 will be a 2nd generation Coyote.

Before anyone gets annoyed with changing a Mach 1 into a Boss 302 tribute, please note that the original owner nuked the original 351 Cleveland and replaced it with a 302 of unknown origin. When purchased, the car did not run so there was no plan to restore the unknown stock engine. The original owner also destroyed the original Calypso Corral orange paint by doing several a really poor repaints in a silver blue metallic. Given the original engine, transmission, and paint are gone, any attempt to restore the car would cost far more than the gain.

So my build plan is as follows:

The car will be a Trans Am look 1970 Boss 302 tribute. No hood scoop, but with all the Boss 302 graphics modified somewhat from the original layout. I want to combine the 1969 Mach 1 hood treatment with the Boss 302 side stripes. A good example for the look is the 1969 Gateway Mustang built for Auto Trader magazine.

Body modifications will be very limited to removing the Mach 1 rocker mouldings and tail trim. No final decision on shaving door handles as yet, but I do like those trick door handles that Kindigit design sells.

Front Suspension will be the high HP front clip, splined anti-roll bar, 13” Wilwoods, and dual adjustable shocks from Total Control Products. The shock towers will be removed as part of the front clip installation to make room for the Coyote engine.

Rear suspension will be TCP g-link (4-link) rear. I am staying with stock rear tubs to maintain the rear fold down rear seat option. Going singal adjustable coil-overs with splined rear sway bar. Rear tires will be 285, with 295 as possibility.

Wheels will like be Team III mini-lite look alikes in a 18” size. I like larger wheels than stock but just large enough to clear the larger brake rotors and calipers. I would like to see 245’s up front and 285’s at the rear.

Interior will be mostly stock appearing with some updates. I plan to redo the Mach 1 seats with new more highly bolstered foam to keep original look but improve comfort and ability to stay planted in the seat. AC is a must and power windows are likely. Modern Dakota Digital analog instruments to replace the original gauges.

Motor/Trans – Second Gen Coyote with 6R80 automatic. Not sure if the engine will be left stock or modified with Boss 302 intake and new cams. I may just leave it stock to begin with and modify later should I decide to seek more power. More likely to install a 3rd Gen Coyote intake as they have been shown to add power while keeping driveability. I obtained a Lokar sport shifter for the 6R80. Looks more like a manual transmission shifter but has a sport mode where you can manually shift the transmission via the paddle shift signals to the PCM.

I am looking to build a vintage looking car with modern engine and suspension. Looking for a chassis that can handle the added HP and handle well enough to be auto crossed at times.

For color, a dark red pearl and staying with the dark metallic gray for the stripping.

So far I have taken the car down to not much more than a shell. The only serious rust issue is the lower cowl is rusted through is several places. I am hoping the repairs can be limited to patch panels, but access is limited to the openings in the upper patch panel. A new cowl assembly has been purchased, so full replacement is now more likely.

The OEM front sub-frame has been cut from the car and the TCP front clip positioned and tack welded. I am cutting out the remainder of the rear frame rails to make room for the new lower TCP frame rails.

Here are a few pics of the car after it arrived home in late 2016.






Alan
 
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#36 ·
holly crap man! I so just went through TCP's website and priced out what I would need to do this swap on my 69 vert. while the front clip is affordable, the suspension and steering to finish it out.. not so much. Is there a way to use others front suspension parts with this? without brakes im well over $8K in parts.


which brings me to this: why did you do with this over other kits that are complete?
 
#37 · (Edited)
holly crap man! I so just went through TCP's website and priced out what I would need to do this swap on my 69 vert. while the front clip is affordable, the suspension and steering to finish it out.. not so much. Is there a way to use others front suspension parts with this? without brakes im well over $8K in parts.
which brings me to this: why did you do with this over other kits that are complete?
Yeah, the TCP weld-in front clip with suspension, steering rack, and shocks is expensive, however not that different from their peers. At one time I considered doing the complete frame from Schwartz performance. A full chassis with suspension, IRS, brakes, etc. was on the order of $28K. Needless to say I rejected the idea. I then started looking at TCP, Heights, and Detroit Speed. The comparison was eye opening, TCP actually looked to be the least costly at the time. I also was leaning toward the weld-in front clip from TCP because my car had suffered some front end damage at the hands of the original owner. The passenger side frame was tweeked a bit and the sheet metal from the rear inner fender aprons needed replacement. So, based on the condition of the car, it appeared to be easiest to ditch the OEM front sub-frame, sheet metal, and shock towers. I am installing a 2017 Gen 2 Coyote, so I wanted the front of the car to be stronger and more twist resistant than stock. Given my constraints and desires, it was cheaper to go with TCP for my project IMO.

That said, my initial outlay for the weld-in front clip was $2.3K including the transmission cross member. I used CJPP for the front clip because of the points I could use toward other purchases. When I went to buy the front suspension, I found that no other vendor sold the full line of TCP parts. Both CJPP and Mustang Depot sold some of the parts, but not all. I also found that MD was charging for the PS rack where it was included from TCP. I contacted CJPP customer service and discussed my dilemma, but they could not accommodate anything not available on the web site. When I priced out the suspension package initially, I had included dual adjustable shocks and 14" Wilwoods. After reading some posts on another Mustang forum, the consensus was that the dual adjustable shocks provided too many adjustments and it was suggested that single adjustable was more than adequate. So I went with the g-machine pro-touring setup, but not optioned out to the Nth degree. The cost of the package with shipping came to a bit over $6.7K including 13" Wilwoods and a late model Ford bracket for the transmission cross member. All in for the front so far is about $9K. In the beginning, I thought I would be more in the $7K range, but I missed some of the extras I decided to go with.

One has to trade off your requirements against cost. Given I expect on the order of 500 crank HP from the Coyote, strength and rigidity were a priority. Over the last month or so I have looked at packages for the rear suspension including the Fab9 rear axle, TruTrac center section with gears, axles, brakes, etc. Again another sticker shock. The rear setup will be on the order of the same amount as the front, maybe a bit less. So is $17K to $18K a lot of money, yes, but the quality of the parts are top notch. I was looking at the welding on the A-arms and they are a work of art.

All in all the plan for the car was a middle to higher end pro-touring restomod. I think the build will be well received by all who look at it when it is done. There is another factor to throw in, I was very fortunate to find a 2017 GT donor for the engine and transmisson. Want to get some sticker shock, price out the Ford Performance Coyote/6R80 combination, about $17K retail plus the controls pack, alternator, accessory drive system, headers, etc. I figure you could easily be in the $20K retail range and possibly a few thousand less if you pick the right vendors. I got my donor car purchased at auction and delivered for $6.5K. The car was only 4 months old when it was totaled out from front end damage and being striped. The car had a junk title and could not be registered for road use again, so I got it cheap. Most builders would not be so fortunate to find a donor like I did. So, compared to paying retail for the drive train, the cheap donor allowed me to spend more on the suspension part of the build. Again I was looking at the end game and the quality of the build.

I will mention that TCP is in or has completed a price increase. On my splined front sway bar alone, it went up $100. Other items went up a few percent or more.

Alan
 
#38 ·
Shock Tower Delete Panel Modifications

Wow, I see it has been a while since I posted anything about the shock tower delete panel install. Initially, I did not order the splash flaps with the subframe kit, a mistake. IMO, the splash flaps are absolutely necessary to align the shock tower delete panels. I ordered the splash flaps from a vendor in San Diego which took 3 weeks to receive them where I thought I should have gotten them in one week. Oh well, scratch that vendor for any future orders.
Once the splash flaps were received, I installed them and noticed that I had to muscle the shock tower delete panels into position to align them. It was like I had to rotate them forward counterclockwise in order for the splash flap to align with the shock mount. I contacted TCP, but simply got confirmation that I had the correct parts for my 1970 Mustang. I was not satisfied with the fit, so I took it upon myself to look for another solution. I thought about getting full replacement inner fender aprons and shock tower delete panels from Mustangs to Fear, but too much added expense and another unknown regarding their fitment. So I decided to prototype changes to the existing shock tower delete panels in construction cardboard as verification of any modifications. The following posts will document the changes and process I went through to achieve the fit I was after for my vehicle.

Alan
 
#39 ·
Prototying Changes in Cardboard

As shown in the picture below, I worked out the necessary modifications by first relocating the splash flap on the existing panels. I then made up a cardboard version of the shock tower delete panels to verify my changes.













Alan
 
#40 ·
Modifying Original Shock Tower Delete Panels

With a modification layout that appeared to work, the next step was to create a modified shock tower delete panel that was a hybrid of metal and cardboard. I chose to cut away the lower third of the shock tower delete panel just below the bead rolled center section. I cut away the lower third of my cardboard panel along the same cut line and used package tape to connect the two. I then installed the modified hybrid panel to confirm it fit as did the full cardboard panel. I did find I wanted to rotate the opening for the A-arms a bit for better alignment, so I added a little wedge piece of cardboard. At this point I was satisfied with the fit, time to move on to metal.





Alan
 
#41 ·
Shock Tower Delete Panel Modifications in Metal

The plan was to stitch weld on 14 gauge metal in place of the cardboard template.

Here is a view of the panel cut to where you can see what was removed.



Here is the 5 1/2" x 15 1/2" x 14 gauge replacement panel.



Here is the panel clamped in preparation for stitch welding.



Here is the first pass on the stitch welding. I made successive passes until all the stitch welds joined, then ground down the weld bead and finished up with an air grinder with a sanding disc.





The same was done on the backside of the panel.



Here are the final results.





I did lengthen the panels as well so that they would mate up to the welding flanges supplied. I have a bit more preparation to do prior to welding in the panels, but for the most part the changes are done.

Alan
 
#42 ·
Radiator Support

I also had located the radiator support and latch support bracket to verify all is aligned properly. I have done corner to corner measurements and all is square within 1/16" and the radiator support is level with the sub-frame. The welding flanges from the sub-frame to the inner fender aprons and shock tower delete panels will be welded in first. The radiator support will be left clamped in place while fitting the engine and transmission. The Coyote and 6R80 transmission make for a large package. Leaving off the radiator support as the modifications to the firewall and transmission tunnel are worked out will make it easier installing and removing the E/T package for however many times it has to go in and out.



After a bit more preparation, I plan to start plug welding in the flanges and panels.

Alan
 
#44 ·
Shock Tower Delete Panels Mostly Welded In

I made some good progress this week completing most of the plug welding for the shock tower delete panels and flanges to tie the inner fender aprons to the new TCP subframe. After having good success with my practice plug welds, I decided that I would just go for it. I found that I liked to weld around the perimeter of the plug weld hole and finish in the center. I was very happy with the results my ESAB Rebel welder provided on the Smart MIG mode. I ran the welder set for the thicker of the metals being joined.

Here are a few pics of the work in progress.

Here is a picture showing the plug welds before grinding and sanding them flat.



Here I have ground most of the plug welds down but some yet to do.



Here are a couple shots from the wheel wells showing the discoloration on the backside and thus the heat transfer.





I should finish up this weekend. I need to pick up some magnets at HF to assist in holding some small patch pieces to fill overlapping holes. In a couple places, the plug weld hole on the shock tower delete panels partially matched up with the old shock tower bolt holes. I have a couple of crescent moon shaped voids I need to fill before final plug welding.

All in all, I thought the plug welding came out great for a novice. Thank goodness for the smart MIG technology, I think made the results better than I could have done without it.

Alan
 
#50 ·
Thanks for the pics, especially that of the MC. I plan to use a hydroboost system on my build. I transplanted a 2004 Mach 1 4.6L DOHC engine into the Factory Five Cobra I built a few years back. I think some games are going to have to be played to get the HB and master in the Mustang with the Coyote. One guy here on the VMF put a Coyote in a Cougar and used a offset mount to shift the HB and master toward the drivers side hood hinge. I am hoping to get my donor 2017 GT in the garage next week to start pulling the Coyote and 6R80, can't wait.

The pictures I have seen of the cars built in your shop are impressive, gives me a standard of quality to work for.

Alan
 
#51 ·
Shock Tower Delete Panels Installed

Over the weekend and a few days more, I finished up welding in the shock tower delete panels. I had a bit more welding to do as well as grinding down the plug welds and finishing up everything. I went back and plug welded in the shock tower bolt holes on the tire side of the inner fender panels providing a more finished look. For a first time effort at doing work of this kind, I am very pleased with the results.

Drivers side shock tower delete panel.





Passenger side shock tower delete panel.





There is still a bit of cleanup and final welding to do, but just a few hours total I hope.
 
#52 ·
Rear Tire Fitting, Wheels and Suspension

With most of the work complete on the TCP subframe install, I have moved on to working on the rear suspension, wheels and tire fitment. I order and received my tires yesterday, Nitto NT05s in 245-40/18 front and 285-35/18 rear. The tech support guys at TCP are working with me to get the right backspacing. The front will be 8x18 with 5" BS, the rear is going to take a bit more effort to determine. I am also working with ET Wheels in CA on the rear BS required. The rear wheels will be 18x10 with a 5 1/2" or 6" BS. The rear G-bar rear suspension from TCP will eliminate the leaf springs, so that gives me about 1" more room to work with. I have positioned one of the tires under the car to verify clearance and so far all looks good. It is possible that a 295 will fit, but I am real happy with the 285 for now. I am going to build a simple fixture with 2x4s to get the tires square to the body and recheck the fit, but I do not expect any issues.

Here are a couple of pics of the 285 in the back, its going to look awesome when done.





The wheels will be the Team III LT-III minilite look wheels. I am after the Trans Am look of 1970 for the car.

ET Wheels by Team III Wheels
 
#53 · (Edited)
Windshield Removed

The trim removal kit I bought had tools in it for removing the windshield which came in handy today. There were two tools, a hook with a pull handle to cut out a chunk of the boding adhesive and a handle and wire tool that could be used to slice through the adhesive around the glass. I broke the wire a half a dozen times, but eventually cut enough of the adhesive to allow lifting the glass. Took all of about 20 minutes for a novice, something else I had never done before.

Here is the question, there is a lot of the adhesive left on the body so is there an effective way to remove it without digging into the paint while trying to scrape out the stuff from the channel? Will goof off or Goo Gone break down the stuff to where it is easier to remove? I was thinking about trying mineral spirits since it worked great removing the adhesive used for sound deadener like Dynamat.

Thanks,

Alan
 
#54 ·
Cowl Replacement, What to Do About VIN Tag?

So the windshield is out, the only rust repair I know of at this time is replacing the cowl assembly. I have exposed all the spot welds outside of the windshield, and once the adhesive is cleaned up from the windshield, I will do the same for the spot welds that were under the windshield.

Question, I know that it can be illegal to remove and replace the riveted on VIN tag, but in my case the entire cowl is being replaced, so what to do? I thought I had read somewhere that the local law enforcement may look at the rivets to see if they have been replaced. Can I simply remove and rivet the VIN tag onto the new cowl or do I need to cut out part of the original cowl and weld it into the new assembly to be "legal". I am in AZ if that matters. I was wondering if I should consult our local Sheriff or MVD, DMV elsewhere, to determine what to do?

Thanks,

Alan
 
#55 ·
After talking with local Sheriff and DPS, I was directed to MVD(DMV in most states). Our local MVD referred me to their Enforcement officer, only in the office on Tuesdays. I met with the Enforcement officer and I showed him pictures of what needed to be done on the car. I showed him my title, registration, and pictures of the VIN tag and markings on the fender aprons. So I established ownership and that the car had matching VIN numbers on the vehicle. The procedure the enforcement officer gave me is Arizona Vehicle Code paragraph 28-2165, "Special Serial or Identification Number." Essentially, I am allowed to move the VIN tag to new metal when VIN tag must be moved to repair the vehicle as a result of damage whether due to rust, accident, etc. When complete, I will submit a form ADOT 4805108 R10/14 to the Enforcement office that documents the VIN tag having been moved to new sheet metal. The form includes an owner statement as to the reason for removing and reapplying the VIN tag. A new AZ VIN tag will be made up with the original Ford Motor Co. VIN Tag info and affixed somewhere on the vehicle, hopefully in a accessible but not overtly obvious spot. I will obtain matching rosette style pop rivets to attempt to maintain as original an appearance of the mounting of the VIN tag to the cowl assembly. These rivets are available on Ebay, but at $10 a pop, not cheap.

The enforcement officer thanked me for coming in. He said it was highly unusual for someone to come in before the original VIN tag had been removed. I explained that I wanted to mitigate the possibility of doing something illegal. I do not believe in asking for forgiveness afterword when a felony could be involved.

I hope this helps others have an idea of the procedure in AZ, however their states may handle it completely differently.
 
#56 ·
Donor Mustang Moved into Garage

I finally moved my donor 2017 Mustang GT into the garage Sunday. Life and other projects had gotten in the way a bit with it sitting outside for 10 months till I could get to it. I am in the process of trying to read out the PCM memory in an attempt to determine the mileage on the vehicle when it was totaled out. The car had been a Hertz rental, only 4 months old when totaled. My first attempt to read out the PCM memory yesterday did not work. I found the Blue Driver OBDII reader requires the engine to be running in order to "connect" to the car. I put out a SOS to our local hot rod lunch group and I have been loaned a ODBII reader that the owner has used on two vehicles when not running, so I will try that later today.

Here are a few pictures of the donor.









 
#61 ·
I finally moved my donor 2017 Mustang GT into the garage Sunday. Life and other projects had gotten in the way a bit with it sitting outside for 10 months till I could get to it. I am in the process of trying to read out the PCM memory in an attempt to determine the mileage on the vehicle when it was totaled out. The car had been a Hertz rental, only 4 months old when totaled. My first attempt to read out the PCM memory yesterday did not work. I found the Blue Driver OBDII reader requires the engine to be running in order to "connect" to the car. I put out a SOS to our local hot rod lunch group and I have been loaned a ODBII reader that the owner has used on two vehicles when not running, so I will try that later today.
Here are a few pictures of the donor.









We use a mobile diagnostic company to do all kinds of computer flashes and code clearin. See if you have one local to you. They are relatively inexpensive, come to you, and have all the latest computer diagnostic scanners from all makes/models. Here is who I use...https://www.fixr.com/sp.rms-llc-mobile-automotive-diagnostics.html
 
#57 · (Edited)
Cowl Repair in Progress

Now that I have a plan for the VIN tag, I started working on removing the old cowl from the car. I started by trying to cut the spot welds on the passenger side edge, but progress was slow and I felt a bit blind in that the original spots welds are far from circular. After looking at the replacement upper and lower cowl pieces, I decided to first cutout most of the upper cowl panel so that I could see what was going on underneath.

First, I removed the rear inner fender apron extensions.







Next, I cut along the perimeter of the upper cowl.





The full extent of the rust damage is revealed!









Before removing the top cowl I was pretty sure the lower cowl was roached, now I am sure!

With the top removed, now I plan to grind away the spot welds around the perimeter. I am going to try grinding them down instead of using the spot weld cutter and see how it goes. I figure if I use the spot weld cutter, I have to grind down what is left of the spot weld anyway. We will see how it goes, but anyone with experience in doing this job please chime in if you know a better way.
 
#59 ·
Wheels and Tires

Last Thursday, my custom wheels from Team III were delivered. I took the tires and wheels into Discount Tire to have them mounted and balanced. The first time I was in the DT Prescott store. The staff was very courteous and did a great job mounting the tires and balancing the wheels. No damage issues at all, just a bit of cleanup to remove the soap residue they use to lubricate the wheel when mounting the tire.

I selected Team III because I wanted a mini-lite look alike wheel, but in a larger diameter and width with custom backspacing to match my Total Control Products suspension. I spent a fair amount of time with Scott at Team III and Mike at TCP fine tuning the wheel widths and backspacing for the car. Please keep in mind that I will have a full coil over 4-link rear suspension, so eliminating the leaf springs gave me a bit more room to work with. I have the fold down rear seat option in the car that I did not want to lose or rework, so I am not mini-tubing the car.

Front 18x8, 5 inch backspacing with Nitto NT05 245-40/18
Rear 18x10, 5 1/2 inch backspacing with Nitto NT05 285-35/18

I was told by TCP that a 305 was possible at the rear, but now that the rear tires are mounted an inflated, there is not a lot of extra room to work with. If I can position the wheel where a 295 will fit, I will upsize on the 2nd set of tires.

Here are a few pics:





The car is about at ride height with the front cross member only about 4.5 inches off the ground. This next week, I plan to roll the rear fenders. I will position the tires and wheels for best clearance, then measure the hub to hub distance between the rear wheels. I will provide the measurement to TCP so that they can custom fab my rear axle for perfect fit. I expect it will take about 4 to 6 weeks to get the rear G-link suspension, Fab9 axle housing fully loaded, and 12.2" rear Wilwood brakes with integral parking brake. My goal is to get the car to a roller status by November.
 
#62 ·
Thanks 69bosssvt for the suggestion. I recognized late last week that the car was missing the control panel with the "Start" button, so I had no way to energize the ignition. I found one on Ebay cheap enough that it was worth it to me to give it a try. The panel is supposed to arrive in the mail on Monday, so keeping my fingers crossed. Even with the control panel, I do not believe my Blue Driver would work since I believe it requires the engine to be running to connect. A neighbor has loaned me a OBDII reader he has used to read codes without the engine running on at least two vehicles, so that is my primary backup plan. I will also be sending off a letter to Hertz in CA to determine if they have any service records on file for the car, and if so, what the last recorded mileage was. Knowing the mileage is kind of a wish list item, something I would like to know, but not having it will not hinder anything.

Thanks again
 
#67 ·
Success Reading Mileage Info from PCM



One of the guys on the AllFordMustans forum suggested I used a generic Blue Tooth OBDII reader and the Torque App. After some more searching, I found the cheap Blue Tooth OBDII reader I bought long ago and I purchased the full Torque App for the Android phone. After some fiddling around to get the phone to connect to the Blue Tooth OBDII adapter, it connected. The Torque app was able to show that it was connected to the right vehicle VIN. I kept poking around in all the menus for the Torque App, but nothing seemed to have the info I was looking for. I finally took a look at the graphing function and it had a number of parameters that could be added to the graph for monitoring. I almost got to the last of the parameters when I saw a mileage number under Miles Since Last Code Reset. The mileage shown was 2635. Now it is possible the error codes could have been reset previously, however unless the car had thrown a code, why would they? So at this point, I have as much information as I could hope for, so I can now move on to disconnecting all the wiring, hoses, CATs, driveshaft, etc. in preparation for pulling out the engine and transmission.

Wow, if that is the total mileage on the car since it was manufactured, I was very fortunate to find it for my donor.
 
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