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1970 Mustang Fastback Boss 302 Tribute Coyote Restomod Build

95K views 508 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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#2 · (Edited)
Stripping Out the Interior

Here are pictures of the interior with most of the dash, carpet, seats, doors, etc. removed. Although there is some surface rust on the floors, nothing severe enough to require panel replacement.












Alan
 
#4 ·
Coyote from Donor Mustang GT

In September 2017, I picked up a 2017 Mustang GT at auction. The car was very low miles and had a junk title, so only good for parts. The car had been a Hertz rental, got in a wreck, and was partially stripped. The engine and 6R80 transmission are what I was after and got them at a great price compared to buying new parts.

 
#5 · (Edited)
Cutting Out OEM Front Sub-frame

The engine compartment was gutted in preparation to cutting out the old sub-frame.



Most of the work was done with a Sawzall which made pretty quick work of the removal.




 
#6 ·
Installing TCP Front Sub-Frame

Using my engine hoist, I was able to install the new TCP front sub-frame and position it for tack welding.






 
#7 · (Edited)
Installing TCP Lower Front Frame Rails

Once the upper sub-frame was positioned and tack welded, the lower OEM frame rails were cut out to allow the lower TCP frame rails to be installed. The sub-frame I am installing is what TCP terms their high HP or full length sub-frame.


[img





This is the progress to date. Tomorrow, a friend will come in to do the welding for me since I am a welding novice.

Alan
 
#9 ·
Dan: The sub-frame connectors are an option you purchase separately. I will get them when I purchase the rear suspension. A nice feature to the TCP sub-frame connectors is an integral driveshaft safety loop. Once the front sub-frame is welded in place, I am debating if it is time to get the front suspension and steering. My thinking is that I need to get the major pieces in place so that I can rule out interference issues. I will likely get the Coyote and transmission in place and then add the suspension, steering, add the PS pump and hydroboost power brakes.

Alan
 
#11 ·
Nice build! I will be watching.

I really think I would spring for the Boss 302 upgrades to the Coyote. If it is going to say Boss 302 on the outside, it has to scream Boss 302 under the hood. The Boss 302 intake will set it off.
 
#14 ·
One way to go which I have considered. What I have my eyes on is the thought of installing the Borla stack fuel injection. Nothing screams engine porn like stack injection. They make one that looks like vintage Webers, yet is modern fuel injection. Borla claims HP with their SI is on the order of 525 at the crank. Can't get that kind of looks or power with the Boss 302 intake setup.

Alan
 
#15 ·
First Round of Welding on Sub-frame Complete

With help from a local builder, the sub-frame was welded into the car. The welder was having issues with weld penetration, especially when welding overhead. Plan is to purchase a rotisserie and go back later and clean up and make another pass to improve the weld quality. I have moved on to cutting out the shock towers, replacing the front inner fender panels and radiator support.



 
#16 ·
Need Source for Front Sheet Metal Position Info

With the passenger side shock tower removed, new front inner fender and radiator support mocked up in place, I need a resource for position information to confirm the sheet metal is properly located. Is there a source that professional body shops use to locate the panels when rebuilding a wrecked car? This is the kind of resource I am looking for. The sub-frame is properly positioned checking both level and square before welding it in. Now I have to get the inner fenders and radiator support properly positioned so that the fender, grill, hood support and latch, etc. all fit correctly when assembled.

Thanks,

Alan
 
#17 ·
Received Controls Pack for 2nd Gen Coyote with 6R80 AT

Fedex brought me a present yesterday afternoon, the Ford Performance Controls Pack for 2nd Gen Coyote with 6R80 AT. I did a quick inventory and all looks to be present. I would like to add that I purchased the Controls Pack through Mike at Levittown Ford Parts. There price was better than other distributors by $150 with free shipping. Mike kept me in the loop all through the purchase cycle as FP delayed shipping twice.



Alan
 
#18 ·
Love the build.

Interesting that you used the Max jax and the engine hoist to get the frame in place. I have the same lift. Works really really well.
 
#19 ·
Interesting that you used the Max jax and the engine hoist to get the frame in place. I have the same lift. Works really really well.
To get the body level on the lift, I found I needed some method of leveling the body. Don't know if it is a characteristic of the Max Jax lifts, but mine does not lift evenly from side to side, even at maximum lift height. So I found that BendPak sells adjustable lift pads for two post lifts that do fit on the Max Jax arms. They work well and gave me about 2" of adjustability at each pad. The adjustable pads are limited to 2" because there is no hole in the Max Jax lift arm as there is in a Bend Pak model. Once the body was leveled on the lift, it was easy to get the sub-frame in place, aligned, level and square. I got my set of adjustable lift pads from Summit, just added the link below to show a picture.

https://jmcautomotiveequipment.com/bendpak-adjustable-screw-lift-pad-with-receiver-each/

Alan
 
#22 ·
I guess one would say that the imbalance on movement of the lift arms is a Dannmar feature, no exta charge! I did not want to spend an additional $240 for the adjustable lift pads, however the ability to get the car body leveled on the lift is priceless. I have to chalk that expenditure up to be just one of many purchases that I did not know I would need to make when starting this project. That said, next tool purchase will be a rotisserie.

Alan
 
#23 ·
Question on Front Inner Fender Panel to Radiator Support Alignment

On my 1970 Mach 1, I am replacing the front inner fender panels on both sides as well as the radiator support. Please take a look at the two pictures below regarding the alignment of the front inner fender panel to the radiator support. In the first picture you are looking at the driver's side. Note that the two ovals holes in the panels align. The second picture shows the alignment of the front inner fender panel and the radiator support. Note in this picture the holes sort of align, but the hole in the fender panel will not align the same, I cannot move it forward to center the two holes as with the driver's side, what gives? Is this normal or is it identifying the panels are not aligned in the same way? The replacement sheet metal is Dynacorn, which I thought would provide a better fit without issues. Maybe this is normal, just checking with you experts out there.





Thanks, Alan
 
#26 ·
I used the alignment holes as a quick guide but didn't depend on them. I used my old before measurements, and did a lot of linear and diagonal measurements to verify square and depended upon actual numbers rather than ends of the sheetmetal or punched holes.
 
#32 ·
Although I appreciate the suggestions, not going there. Too much invested in the car and not willing to get hurt trying to save a few bucks with a home made solution.

This has gotten off topic, no need to continue this.

Alan
 
#33 ·
Aligned Shock Tower Delete Panels

A couple of weeks ago, I received the rubber splash shields that work with the shock tower delete panels. TCP sells them separately from the weld-in front sub-frame, so I did not get them in my original order. Turns out, the only way IMO to properly position the tower delete panels, is to use install the splash shield and use them to correctly locate the tower delete panels. The splash flaps fit around the upper A-arm support with only about a 1/8" to spare on each side, so when centered, the tower delete panel is correctly positioned. Anyway, I completed the initial fitment, now I need to remove the panels and grind clean all the mating surfaces in preparation for welding. I plan to tack weld the tower delete panels with the inner fender aprons initially, then fit all the bracketry for the hood, install the fenders and hood to verify all the sheet metal is where it belongs. I will then tear it all apart and final plug and stitch weld the tower delete panels and inner fender aprons. I will leave the new radiator support clamped in place only so that installation and removal of the Coyote and 6R80 transmission is easier during modification of the transmission tunnel.



 
#34 ·
Front Suspension Is On Its Way

The week before last I ordered the G-machine front suspension for the build. The G-machine package is geared toward a high performance pro touring type build. You can configure the package somewhat in that you can choose the finish, hardware, end link styles, brake size, shock type, and sway bar. I would say I put together a middle of the market package and still went into sticker shock. Lets say without quoting numbers, it was a bunch! Well you know what they say, the good stuff costs, so I am hopeful the parts are equal to their reputation. I went with the single adjustable shocks/coil overs and the 13" 4-piston Wilwoods.

I got notice that UPS picked up the parts today, so I should have the stuff in about a week at my door.

For those who might like more information, here is a link to the TCP data sheet for the weld-in front clip. It shows the sub-frame, suspension, steering rack, etc.

http://www.cachassisworks.com/Attachments/DataSheets/KCXX_DS_WEB.pdf
 
#35 ·
Suspension Components Arrived

The brown truck brought the first delivery of front suspension components today. I have been going through all the boxes and creating an inventory for what I received. So far I have accounted for:
1. Power Steering Rack ( A surprise since it was supposed to be back ordered )
2. Splined front anti-roll bar.
3. Spindles
4. Upper Control Arms and HW
5. Hubs with bearings and studs
6. Drivers and Passenger side 13” Wilwood rotors

More to do today and then enter items onto my parts spreadsheet.

I have removed the drivers side tower delete and front inner fender apron so that I could remove the protective coatings in the areas where the parts will be welded. I am also putting holes in the panels for plug welding where applicable. I installed the hood latch support bracket that connects the front of the sub-frame to the top of the radiator support. Good thing I did, I pointed out that there is an errant picture in the TCP installation instructions. One picture showed the radiator support to be in front of a bracket for welding, yet another pictures showed in behind. The bracket and radiator support did not fit well together when the bottom of the radiator support was in front of the welding flange, so I moved it to behind the flange and the components lined up much better. A lesson to remember as some of the feedback I have received here on VMForum was to assemble as much as I can before even tack welding the parts together, now I know why. In addition to finishing the inventory, I hope I will be able to reassemble the drivers side tower delete and front inner fender apron panels. Friday, I hope to get the passenger side tower delete and front inner fender apron panels removed and prepared and then reassembled. With those items done, it will be time to check my parts inventory to see if I have some of the other front brackets required to mount the front valence, bumper, inner fender liners, fenders, grill, etc. I intend on assembling the entire front end of the car to verify that the inner fender aprons and radiator support are in the right place before disassembly and final welding.
 
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