TNT - MK3 FFR Cobra Build Thread

[tnt_motorsports]

Well folks, it is that time! I brought the chassis and some parts home from storage last weekend (Friday). I have spent Sunday prepping the garage, removing sheet metal, welding on the control arm brackets and painting the 8.8 rear end housing. Today I hope to install the front suspension and begin rebuilding the rear end. I hope you will be patient with me because I'm sure I will have lots of questions. I am beyond excited for this build.

Build details are as follows
FFR Cobra MK3 F5R100 5447 donor kit (I'll be converting to a complete kit where possible)
427 SBF with EFI and a TKX transmission (TBD on build or bought)
11" Stock Mustang brakes
8.8 solid axle rear end with 3.55 gears

Todd

[Justin]

Enjoy the process and share your adventure! Looking forward to it.

[Blitzboy54]

Awesome, I am curious on the back story. Are you the original owner and been on hold for some time or did you purchase someone else’s kit?

[Jeff Kleiner]

Cool! I like seeing the old cars resurrected. I've done full builds for customers on two Mk3s that were 10+ year old barn finds and did body and paint on two others that languished untouched for years until their new owners saved and finished them.

Not that it matters much but based on the F5R1005447 number I'm pretty certain that you have a Mk3, not a 3.1. The only significant differences are that the 3.1 uses different steering shafts, will accept a Wilwood pedal box and has revised engine bay aluminum to allow use of the 4.6 Mod Motors.

Have fun!

Jeff

[tnt_motorsports]

Thank you all for the well wished and feedback. I am very excited to get this going. I had a great day in the garage yesterday working with my oldest son who is 23, rebuilding the 8.8 and prepping for the front control arm installation. I decided to paint the aluminum panels so the control arms are awaiting that.

Thank you Jeff for your insight. I believed it to be an MK3.1 based on feedback, but I wasn't exactly sure.

The back story is we exited the camping hobby last fall by selling our 36' TT. I loved it and enjoyed all the family trips and memories along with attending many Sprint car and SLM racing events across the Midwest. The deal with the boss was if we sold the camper that could be the Cobra fund. I happened to luck out and find this car compliments of @timmil, what a barn find and I'm now on my way!

https://thefactoryfiveforum.com/show...-Base-Kit-SOLD

Todd

[tnt_motorsports]

Great day / night in the garage yesterday with my oldest son. We mounted the front UCA, LCA, spindles and shocks.

We also tried to rebuild the rear end gear with the 3.55 swap I am doing, but run into some issues with pinion shimming. We will resume the fun today! I'll post some pictures today or tomorrow of the progress.

[tnt_motorsports]

Another good day! Got the rest of the front suspension items installed including the hubs. Also managed to get the rear differential set up with the 3.55 installed. IMG_2924.jpgIMG_2923.jpgIMG_2922.jpg

[gbranham]

Nice! You should replace those upper control arm dust boots now vs later. Mine cracked before I ever put my wheels and tires on it.

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[tnt_motorsports]

Another productive day in the garage. Rear control arm’s mounted, rear coil overs assembled, fuel tank assembled. I bought a QFS 340LPH pump. It has -6AN fittings. Everything is E85 compatible.


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[tnt_motorsports]

Another productive few hours. Steering rack installed, upper ball joint boots replaced (thanks @gbranham) and tie rod ends installed.

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[Mike.Bray]

Another productive few hours. Steering rack installed, upper ball joint boots replaced (thanks @gbranham) and tie rod ends installed.

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Is that a manual steering rack? Now is the time to convert to power steering. I started out going with manual but the forum convinced me to go PS. It is by far one of the absolute best decisions I made, the car is pure joy to drive with it. And with the increased caster you can run it's much more stable.

[tnt_motorsports]

Hey Mike, it is a manual steering rack. It is what the kit was ordered with. I have contemplated swapping it out, but for now wanted to try and keep moving forward. Thanks for the tip, I will continue to soak on it.

Todd

[Mike.Bray]

Hey Mike, it is a manual steering rack. It is what the kit was ordered with. I have contemplated swapping it out, but for now wanted to try and keep moving forward. Thanks for the tip, I will continue to soak on it.

Todd

There's a lot I love about driving my car. The looks, the insane power, the sound, the handling, the waves and thumbs up from everyone young and old. Two decisions that really add to the enjoyment of driving are power steering and the hydraulic throwout bearing.

[Jeff Kleiner]

It’s a sermon I’ve been preaching for years. Trust me, you wouldn’t regret going with power steering, especially combined with the geometry of the FFR spindles.

Jeff

[gbranham]

I'm only a few dozen miles into my MkIV, with power steering. My MkIII was manual steering. It's a completely different experience. The MIII was fine a cruising speed, but parking lots and slow speeds required some oomph. Totally worth it to do if your budget can take it (it's not terribly expensive), and way easier to do now vs later.

[tnt_motorsports]

Another somewhat productive day in the garage. Front brakes mounted, rear end and fuel tank installed. My wife said it’s actually starting to look like a car.

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[TTimmy]

It’s great to see these abandoned projects rescued; looks like you’re many quick work of this.

I took over someone’s project last year and am really enjoying the rebuild.

Keep up the good work!

[tnt_motorsports]

Ok folks, I need a little help please. I am trying to use an SN95 pedal assembly in the MK3. The Wilwood pedals won't fit per FF, and the brake pedal is hitting the 3/4" tube running across on the foot box. Can someone please help with what I am missing?

Are there any other mods I should be looking at before I paint and mount these pedals? I intend to use manual disc brakes in the car.

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Thanks!
Todd

[michael everson]

Couple of things. First remove the large round spacers (4) on the front of the pedal box. Crush them in a vise or bend the plate enough to get them out. Are you planning on power brakes? If no you need to modify the brake pedal to reduce pedal effort and improve the leverage. I highly recommend power brakes though. Very easy to do at this stage and won't cost much. PM me for my number if you want to discuss further. I do it all the time.
Mike

[tnt_motorsports]

Thanks Mike for your assistance! I will shoot you a text to discuss further.

Thanks
Todd

[Blitzboy54]

Love rehab projects. Following along with great interest.

[tnt_motorsports]

Well a busy couple days in the garage on the Cobra.

Yesterday I test painted a couple panels after buying a new spray gun from HF. It works good but I thinned the paint too much. I fixed that and will repaint the firewall tomorrow maybe.

Today I’ve managed to mount the pedals, brake booster and master cylinder. I’ve installed the steering shaft and bearings. I also played Cobra Tetris with the sheet metal for the foot boxes.

I’ll post some pictures later.

[tnt_motorsports]

Another decent day.

Driver’s side foot box installation almost complete. I broke my last 1/8” drill bit so I ended early.

The passenger side foot box is completely drilled and ready for paint. I removed it to clean and prep the panels.

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[tnt_motorsports]

The in-laws were in town until Thursday so it was a slow week working on the Cobra. I was back at it this weekend. I've fit and drilled the cockpit sheet metal.

Next will be brake and fuel lines along with painting the sheet metal.

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[tnt_motorsports]

Well I took advantage of a nice long weekend to get some work done on the car. I painted several panels and installed the foot boxes. I also completed the brakes by running brake lines and connecting the caliper hoses. I also installed the clutch cable adjuster it’s coming along but still a long way to go.

Happy Memorial Day. All gave some and some gave all. What a great country we live in that we can enjoy things like this because others paid the ultimate sacrifice.



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[timmil]

Todd: Wow! Looks a lot better than it did in my garage! I haven't been able to watch this much as I would like since I added a new race car to the fleet. Have you decided on a color yet?

Tim

[tnt_motorsports]

Thanks Tim! I haven't been able to settle on color with the boss... I wanted to do a blackout version, but she said it would look too much like a buggy (as in a horse and buggy) that is all black. I'm open to suggestions but was thinking like a metallic grey or orange as other options.

Todd

[timmil]

Thanks Tim! I haven't been able to settle on color with the boss... I wanted to do a blackout version, but she said it would look too much like a buggy (as in a horse and buggy) that is all black. I'm open to suggestions but was thinking like a metallic grey or orange as other options.

Todd

It's funny that you mention Orange. I had wanted to do it in Orange with ghost stripes so that it would look cool against my 77' 280z.

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[tnt_motorsports]

I finally made it back to the garage this week / weekend. We were in Alaska for our 25th anniversary the first 2 weeks of June and a wedding in KC last weekend has put a crimp in my work, but I have to keep the boss happy, she is working with me on the car...

It has been tremendously hot here in eastern Iowa, so my work in the garage has been limited. I did manage to get the firewall painted and installed, and started to run some fuel lines.

I also needed to shore up my chassis dolly. The 2x4's and the plywood caster mounts were showing signs of distress. I feel much more confident in the dolly with the modifications I made today. I added a 2x6 to the bottom and a vertical 2x4 on the ends.

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[tnt_motorsports]

I've been plugging away in the garage the last couple nights for a few minutes on fuel lines. I have them completed from the fuel tank to the firewall. I will leave them as is until I figure out engine and the fuel system for the motor.

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[tnt_motorsports]

Another productive weekend in the garage. I managed to paint and install the interior sheetmetal, I routed and clamped the fuel tank vent hose and started on the harness install. I have the fuse box installed and the front harness roughed in. It is coming along nicely.

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[gbranham]

What's going on here? And your gas tank vent hose really doesn't need to be that long and snake all over the place. A foot or less is fine.

Greg


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[tnt_motorsports]

Thanks for the feedback, Greg on the vent line. I wanted to avoid using a charcoal canister if possible, so I thought (maybe incorrectly) that this might help.

As far as the brake lines, you are seeing 3 different lines. One is the caliper hose to the union, then the hard brake line is the one with the funny bends. I was using up extra length and didn't have enough length to do a circle. The last line is the jump from the axle back to the frame.

[gbranham]

Thanks for the feedback, Greg on the vent line. I wanted to avoid using a charcoal canister if possible, so I thought (maybe incorrectly) that this might help.

As far as the brake lines, you are seeing 3 different lines. One is the caliper hose to the union, then the hard brake line is the one with the funny bends. I was using up extra length and didn't have enough length to do a circle. The last line is the jump from the axle back to the frame.

Gotcha. For what it's worth, you don't need coils in your brake line. Not needed on our frames. If you wanted to clean those up have them generally follow the frame, you could simply cut to length, reroute to hug the frame, then reflare. Once the aluminum and body are on the car, you won't really see them, though. But I fear it would be difficult to straighten those lines with all the bends in them. Would be better to start with fresh brake line if you wanted them a little tighter to the frame.

Greg

[gbranham]

Also, these bolts are going to prevent your upper trunk aluminum from sitting flush on the frame.

Screenshot 2025-07-07 115003.jpg

[tnt_motorsports]

Yeah, I am aware of that. My thought was to drill out a couple holes for them to pass through. I figured the Kilmat and carpet should cover them up.

[tnt_motorsports]

Yeah, I am not overly excited with how the rear axle brake lines turned out, but they are done for now. You are correct that I could install new ones cut to length and straighter. I have several items I want to get done, but I will likely come back and redo these at some point. I need to find better brake line source than the AutoZone ones. I needed a couple lines to finish my brakes, and those things were awful to bend and flare. The FFR ones were nice and easy to bend and flare if needed.

As always, Greg, thank you for the insight and feedback.

[tnt_motorsports]

What's going on here? And your gas tank vent hose really doesn't need to be that long and snake all over the place. A foot or less is fine.

Greg


Screenshot 2025-07-07 111704.jpg

Well Greg you quilted me into fixing this sooner than later. I bought some tubing and fixed it tonight. I've also got the radiator installed. Thanks for keeping me honest!

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[gbranham]

It is somewhat more direct, I'll give you that!

Greg

[tnt_motorsports]

Progress on the Cobra has slowed some. It's been pretty warm in eastern Iowa and the tasks don't show the same level of competition. Front and rear harness run with connectors installed for the FFR lights. Horns installed up front and drop trunk in the rear.


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