ModestMotorsport

Some back story. I've been looking for a Foxbody of an FC to build a new time attack car and to go rub doors with a friend of mine at drift events. The guy selling this car wanted WAAYYY too much money, but eventually came around.



I dragged this thing out of a field where it had been sitting for 6 years, and it turns out that it still runs! Wild! Too bad I don't need that bit.



This was a complete car. I was looking for a good rolling shell. So there has been lots of broken plastic to throw away. As well as my least favorite job of building a cage for any car, removing the sound deadening.

ModestMotorsport

Begone foul copper snake! But dont go too far. I still need quite a few plugs from you. I haven't completely stripped a car down for a complete build in probably 7 years. I forgot how much it sucked.

ModestMotorsport

This damn car had almost 50 (!) pounds of tar in it! That's wild! Double layered in many places. If I ever find myself in position where I am building another FC, it is going to be sent off to get the acid dipped or dry-ice blasted. This wasn't worth it. Now all the fun stuff can begin. Time to build the roll cage.





And for those curious, 91 FC, NA car. Had 41 pounds of wiring in it. This is not counting all of the proprietary brackets, nuts and bolts holding the wiring in. Mazda did not skimp on the materials in the 80's. I expected a bit more lightweighting from them.



A question for anyone that has installed a fully manual pedal box. I am planning to install a Wilwood or Tilton floor mounted pedal box with a ratio of 5.25:1- 5.75:1

Anyone that has installed a manual brake system on an FC with 4 piston front brakes and single piston rears, what size master cylinders did you use? My calculator suggests 7/8" front and 5/8" rear or fairly close to it.

WondrousBread

The amount of one-off bracketry on this car is shocking. That's not a complaint; they spent a ton of time on that sort of thing. Also the quantity of hold-down points for the harnesses, the thickness of the carpet, the sound deadening (as you've noticed), etc. Never mind that almost no parts on this car are shared with other vehicles, or even with earlier / later generations of Rx7.

I didn't realize it was unusual until I worked on some other cars, but the amount of work Mazda put into these cars is astounding. Clearly it was a labour of love.

Nice work so far

ModestMotorsport

It certainly explains why these things cost so much back in the day. There was probably 100 pounds of easy to remove weight that wouldn't have made the car any worse to drive or live with.



This is getting close to as light as the car can get. There is still some unneeded metal and brackets to cut out. The exhaust is still on it, though I don't know what what I build will be any lighter; and the factory gas tank is still installed with, I think, about a 1/4 tank of ancient gas in it. That will be replaced with a fuel cell. Maybe lighter? I hope so! It's also sitting on some heavy 18 and 17 Nissan Z wheels which will get replaced with something lighter. Rear quarters are going to get cut and replaced with fiber glass which may cut a few pounds.

All this is to say, this bodes well for the fact that the car has to weigh less than 2700# at race weight. I decided to build the cage out of 1.5"x.095" tubing. I'm locked into building it light. This should be pretty fun with somewhere between 450-500 horse power and crazy short gearing.

WondrousBread

Does your chassis have a sunroof? You can save a good amount of weight by removing the sunroof and frame. Also gains you some helmet clearance, though obviously you'll need to put a plate over the roof or something to fill the hole.

After that you could do lexan for the rear hatch maybe, that glass is really heavy. Beyond that you'd have to start getting very creative to make it lighter.

ModestMotorsport

It does have a sun roof! I would like to keep it to get smoke out on drift days. I have been toying with the idea of pulling the frame and motor and just building a few brackets to latch the roof panel on.

Rear glass is staying in for the time being, until the radiator gets moved back there and a rear firewall gets built. This poor thing is going to sit outside most of its life so it needs to stay as water tight as possible. Also, I just hate Lexan windows. Cant keep them clean. They're always scratched. Getting big pieces is a pain. Bleh. Getting creative with the angle grinder seems like the better solution.

ATC529R

Looks like a great build. Just as impressed as how well some people make threads. Nice pic as well. Sub’d..

ModestMotorsport

You want some pictures? All this has been cell phone pictures. Here is some of the stuff I work on at the day job.

ModestMotorsport

The cage is started! This is the easy part. The A-pillar bars are going to be a chore. Going to cut the windshield out of it tomorrow for that. Hopefully the neighborhood cats don't find it and use it as a bed.

ModestMotorsport

Today is the first day that I have ever regretted not working at a body shop. Cutting this windshield out with crap Hazard Fright tools was a challenge, but I did it! Having only done things like this in a shop setting, doing it now solo is much more difficult, but its a great workout!



Truck bed for scale.


And the sunroof has come out too. Turns out that the mechanism didn't work, and I wouldn't be able to service it once the A-pillar bars are in. That's a big "No No" in my book. It's also HEAVY way up high. The whole thing turned out to be almost 30 pounds! Over head. I still want to be able to pull the top off. So hopefully I can find some twist lock latches and good seals for the top to keep water out and be able to remove it for drift days; otherwise its getting welded on.

ModestMotorsport

Symmetry be damned. Measure that **** with your heart! Harness bar wont go in until the drivers seat position is finalized.



This a-pillar bar was tricky to keep away from passenger heads. Took four bends to keep it tucked up and touching the pillar and roof structure the whole way. Or at least most of the way. Few things annoy me more than a cage that blocks the drivers view.

ATC529R

You anywhere near Helen ga?

ModestMotorsport

Athens. About an hour and half south.

GeenIdee

Nice project. My car weighs around 2800 I think, not much saving effort.
Stripped interior except for dash and all behind, roofliner en door panels. Rear cage, carbon hood and frp front bumper. Nothing else fancy so far. Its a turbo car also.

My goal, if I'm able to rebuild the car some day, would be as close to 2200 as possible. For an n/a I know it's possible.

ModestMotorsport

A 2200 pound race weight would be a real struggle, even with the rotary. This car could never be down in that category. A lot of metal is being cut out of the car that's not needed. Not 400 pounds of it.

WEAR YOUR SAFETY GLASSES KIDS! It still happens to the best of us.



I ditched the other A-pillar bar. It didn't tuck up high enough for me to feel comfortable, so I made some more conventional pillars. Not as close to the pillars but more room for the passengers' heads, which is more important. I cant say that I recommend building a cage during a Georgia thunderstorm, but it's a fun thing to add to the resume.



Finally. Some pornographic racecar parts are trickling in. This Tilton pedal box is thing to behold. This is going to be dangerous. If I love it, I will have to order one for my Miata too.

ModestMotorsport

I found were some of that cut off wheel went. It made a nice hole in the fender of my Miata...



This is the first time I've used my roller on anything thick walled. What a work out! but it allowed me to bend a windshield bar that perfectly followed the windshield frame.





And welded in and lightly gusseted.



I should have put the dash bar in place first though... Welding in the windshield bar and gussets pulled the A-pillars in about 1/2 inch per. Oh well. I guess I'll bust out the porta-power for that final fitting.

ModestMotorsport

Passenger door bar, dash bar and trypophobia A-pillar gussets are in. Only the drivers door bar, which is already bent, and firewall braces to do. Harness bar cant go in until seats are mounted. I don't know when that will happen though.



Think I can fit this 335 from a Gen1 viper on the back of an FC?



Noob question.
Am I reading correctly that I can use a 1.8 Miata differential in my NA FC housing and use NA FC axles without issue? Because that would save me an awful lot of trouble and expense.

Less fun news. I've been waiting on Grannies Speed Shop to send me a swap kit for 9 weeks now. They've lied to me every time I've gotten on the phone with them. Trying to get a refund through PayPal now. I have no faith that anything I've paid for will arrive. I could have had the engine mounted by now but I wanted the quick and easy solution. This has been neither of those things...

Greener

There’s a thread in the v8 section regarding Grannies...

gracer7-rx7

iTrader: (16)

That roll hoop is the oddest shape I've ever seen. Most shops try to keep it wide at the top to offer the most protection in case of roll over. you did what looks like the opposite...

ModestMotorsport

Unfortunately for me, I didn't see that thread until after I placed my order. And that was started years ago! Surely they've gotten better! I told myself...

The a-pillar bars have a 90 parallel to the ground to curve them toward the top of the main hoop. I'll get a picture. All of the bars are fully tucked against the body.

The decision was made to make the main hoop that shape because it is exactly 8 feet, which is a much less expensive than buying a 20 foot tube and using 9.5 feet, which is what the length would be to have it touching all the way around. It is literally a $240 cost savings for me, on a car that is never going to be used in competition. And I don't keep tube on the shelf or buy it in great enough quantity for it to be cost effective. If this were a customer's car, for sure. Make it huge, but they would be paying for it.

ModestMotorsport

-For Gracer

This is how the A-pillar bar attaches to the main hoop. Somewhat similar to the old NASA style halo roll cages



There is also this much room or less all around the cage to the body. That coupled with me being 5'6" and I'm not too worried about getting a dent in my noggin.

ModestMotorsport

The cage is done! Yay! I painted it silver... Boo... Boring. Round two will be orange.



Parts are arriving in piles, slowly. Starting to get things sorted as far as the ergonomics are concerned.



What I didn't expect was how difficult it would be to get a full size seat into the car. I'm used to fitting race seats into Miata(s) so I'm no stranger to it, but it was a surprise considering the dimensions of the car. I bought an expensive Corbeau seat mount with sliders (not pictured) hoping that it would allow me to get multiple drivers in and comfortable at the same event without hassle. That didn't work. The seat was basically touching the roof. So no sliders. No Corbeau bracket. Humps cut out. Seat on the floor. Maybe a floor drop pan in the future. I hope not.



This car came with an absolutely trashed interior. Literally the only thing that I needed from the interior was the dashboard. I didn't get a good one though. It was and still is falling apart every time I touch it. Out came the glue, string and clamps. Hopefully it stays together long enough to glue some carpet to it until I want to spend the money on a nice dashboard.



Finally a weird little dream come true for me. I have always wanted a two spoke steering wheel. Ever since I saw the Sparco R215 in MADBUL, I knew I had to have one. This isn't quite once of those. I couldn't quite bring myself to buying a blue steering wheel. I've also haven't a car where it would work from an ergonomic stand point. All the two spoke wheels have a very deep dish, which would put the wheel in my chest in most cars. Not here though!



OMP Rally/ OD1950. Good stuff!

ModestMotorsport

Progress is slow. Life in the way. Blah blah blah.

I made a rear bash bar/ Trailer hitch. The 'light' plan is to be able to tow a trailer with spares and tools to the track behind this thing once it have proven itself. Front bash bar too. I'd like to add a jack point to it and something to support the bottom of the bumper once I know what the front bumper situation is going to be.





I also finally got that pedal box installed in this thing. Someone put a steering column in the way though! Jerks. Luckily the pedals on the Tilton box can be offset to the side. That helped a lot.



All that's great. Dash board has been in and out a dozen times for trimming and fitting around the cage. The reservoirs for the three master cylinders are going to mount in the upper center of the dash with a cover to keep them out of the sun. Currently saving up the buy the beefy transmission that's going behind the beefy engine. I cant get those two in place until i have them both. And once those are in, I can measure for a driveshaft and see what radiator will fit.

ModestMotorsport

Ever slow progress. Got the master cylinder reservoirs mounted, sealed up the firewall, and decided to weld up and seal the sunroof.



I never open sunroofs in my street cars, There is no reason to think that I might do it on a racecar. The skin on the inside of the roof was gutted, welded in at 6 places and filled with seam sealer. Should do the job!