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Discussion Starter #1 (Edited)
The conception and birth of our rally team. (For the record)

In a snowy Michigan wood with the distant crackle of rally cars permeating the frozen air, a patient group of Rally-fans conversed:
Someone asked, “Jake aren't you cold?” “No” I responded unremarkably. “But it’s Sno*Drift, and you’re not even wearing a coat” they said. After I took a moment to breathe a lingering waft of race gas hanging in the air, I looked down and explained “… My Fervor for the sport keeps me warm.”
And so was coined the term that now defines our desperate and burning passion for rallying.

When we decided to build a car we knew it would be a Subaru, that for us was a given. The GC era Impreza is a lightweight, inexpensive and proven rally machine. So it was settled, with one remaining minor but unwavering detail; I am a wagon man. So, we discussed an open light concept for our wagon build centered on lightweight and driver control. We also wanted to build it all ourselves…

Bear with me while I get us up to speed here...
 

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Discussion Starter #2 (Edited)
The last two owners of the chassis both planned to build it for rallying before it got into our hands. We bought it for $300 and it was time to manifest its destiny.





We wanted the car to hold together however long it takes for me to destroy it properly. So we decided to really get after rust. The rear drivers strut tower had a tiny spot on it but we knew we'd find a lot more. Regular Subaru quarter rot was our biggest concern so we just went ahead and took it apart:

Removed underbody coating in the area, drilled the spot welds holding the inner "tower liner" and slid it out.


Same story for the top plate (note this hole was barely a buble in the paint before we went poking around):


Just as we suspected. This is a rare photo of the epicenter of subarus rear quarter rust issue (as we hypothesize) and seems to be a real structural issue.


Spent a lot of time with a flap wheel, wire wheels and grinder as cutting much more out and we'd basically be building a new unibody back there. Hope we got it all!


Popped that back together and moved on to another trouble zone (see bottom of photo, rear/bottom corner of the car)



Just simply replace this whole peice with an OEM Panel ($120?!)


Light issue removed on the rear wagon side window corner


Looks good to me. Get the bondo.


Battery tray:



If you're thinking about using this stuff- Don't kid yourself.


Flap wheel gets it though


Another spot:


Cleaned that up a bit more and popped our piece on

 

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Discussion Starter #3 (Edited)
Preping seams for stitch welding





We are removing any unnecessary metal that doesn't contribute to structure. Lot's of this kind of stuff.


REALLY gutting rear doors. When you cut this much out of a door, it looses all structure and becomes a floppy mess. Without the original rigidity we would run into big weather/dust seal problems. We have a very lightweight solution for that problem using wire tension you'll see later in the build.




We've removed all underbody coating for two reasons. 1.) It weights to much (certainly arguable but we went for it) 2.) This way we are able to intimately know every inch of the car and ensure that we aren't missing any corrosion or bad surprises. Being thorough feels good.

 

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Discussion Starter #4 (Edited)
Cage Building

My co-driver and I have it in our heads that we need to learn everything first hand. Without instruction and without software we jumped in. Thanks to sites like this we are able to grind our way to a cage we're proud of and confident in. (Outside of Rally America and NASA rules, Ziptie rally's build on DirtyImpreza.com was our bible. Thank you everyone who contributes this type of information for the world!)

Being a couple of people with absolutely no idea what we were getting into we had a lot to learn if we would eventually have a cage at all, (let alone a cage we felt good about). So needless to say there was a TON of reading and research that went into this. That being said, we are obviously NOT EXPERTS as this is our first cage, but please feel free to ask questions and hopefully this is a place to find answers.

DOM: (2X 21'-25' long sticks of 1.75" tube) and (4X 21'-25' long sticks of 1.5") Both with a wall thickness of .095" as per RA rules. This much tubing is theoretically enough to finish the cage if you make no mistakes. We got a great deal on it at about $350 (I'll correct me if I'm wrong later, but that's the ballpark)


Co-driver getting a bender stand ready to be mounted too (had to get this photo in there hahaha)


Brand new JD Squared bender all set up!


We shimmed a harbor freight notcher and in the end were quite happy with it although it would have been a limiting factor if we tried a couple of more interesting angles. Still notched nice and straight.


Making our first cut (Main hoop)


First bend


Before you know it... Freakin' main hoop. YES


This is about when we started to really understand how incredibly accurate we needed to be. We realized only now how lucky we got that our main hoop came out so tight on the first try.


We spent a lot of time just staring at this fish line to make absolutely certain that we were perfectly straight. Lookin good.


One of our first notches


THAT was a gratifying weekend


Forming main hoop footplates in position for a perfect fit. We attempted to use many faces to add structure and contact as many unibody panels as possible.


Tacked.


Second rear stay tacked in


Slowly working the next triangulation...


Starting to look like something here


Now that we're happy with what we have back here, co-driver Derek starts the first full welds on the cage tubing.




Now on to some lower rear supports. The Back of the cage is almost done.
 

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it took a rally long time to load those photos... like the rally wagon! i gotta see videos when you get it out in the dirt!
 

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Discussion Starter #8
Thanks guys! Yea These photos are huge, sorry. I've got months more progress to post so stay tuned!
 

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Discussion Starter #11
Lol, I didn't realize they were really taking so long to load. I'll get to work re-sizing asap. Sorry about that.
 

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Discussion Starter #13 (Edited)
Half laterals (tubes from top of the main hoop, along the A-pillar, to the front floor): These were, from a planing standpoint, quite challenging. The issue is getting the twist angle just right, as each of the two bends would be on a different plane. As always absolute precision was non-negotiable. We bent up our first one and knew it wasn't going well, we had the twist angle wrong. So during a long smoke break my co-driver and I started going back and forth forming an idea that eventually saved us from ourselves.

As we sat staring at our mess, we realized the the 1.5" tube fit quite well inside the 1.75" tubing. Meaning to us that maybe, just maybe, we could cut our half lateral in half and make a sliding jig that we could twist and lengthen/shorten until it was in the car perfectly, and then tack it in place remove from the car and reproduce.




Here Derek stares wondering at our Jig in the car. (I hope this is making sense to you now)


We are also at this time able to make sure we produce a tube that will fit exactly how we want it. So we were also able to sit in the car and decide how far forward or back was ideal for line of sight out of the windshield. Our mistake ended up only making things better despite the tube waste.

One more smoke break for good measure (literally) and back to the bender.
(we got tired of losing our channel locks.)

As we got close to our ideal bends we started comparing with our jig quite regularly to make sure we were precise.



BAM half lateral. It is so tight we made ourselves a new problem... How do you weld the front? (Our answer to come later in the build...)
 

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Discussion Starter #14
The begining of front footplates under half laterals look like this. Again trying to contact many unibody panels. There will be a vertical plate as well.



We initially created this sill bar from 1.75" DOM including the allowed bend for ample seat clearance. We later realized we could do it with 1.5" DOM instead and scrapped this tube.


We were building the car to be legal at NASA as well as RA events, so basically always tried to stay within both sets of rules. In the case of sill bars, RA does not require them, while NASA does. So to us that meant we needed them in the car. After we welded everything together we made another discovery while reading the NASA rules:
"3.8.14.2 Rally America
Any vehicle with a Rally America log book that is currently legal to
run under Rally America rules may request to be inspected
according to that rule set. If passed, it is legal to compete at a NASA
Rally Sport event.
NRS rules apply for all safety gear worn by the
racer"

So basically in this situation, We could have left sill bars out if we decided.

Anyway, we were out of 1.75" DOM after the waste from the first attempt and the stupid sill bar so we couldn't work another half lateral at the moment and we just enjoyed an eye-full and a break...

(So did my 2.0 VF39 Forester DD and my yota)
 

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Discussion Starter #18
Thanks a lot everybody! We've spent a lot of time draining ourselves on the car, so the guys and I can really put compliments to good use.
 

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I hope to be doing this exact same build in the coming years. Thanks for the blueprints! Looking forward to the rest of your build. Thanks for documenting it all!

-Brian
 

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Discussion Starter #20
So, we haven't made a habit of agreeing to quickly about whats best for our concept. Every tedious decision is made by carefully examining all options against an utter obsession for weight reduction. Lotus founder Colin Chapman said it best: "Simplify, then add lightness". While trying to choose a doorbar design we were conflicted. "X"?(heavier), or no "X"?(lighter)



It wasn't easy to decide, as there is clearly more to consider than only weight in your safety cell. We decided to sleep on it and remove the roof in the mean time.

Start by drilling spot welds along all edges.


20 minutes or so later, it seriously just popped right off. So easy.


We have heard rumors that the roof is structural enough that once it's popped off the walls will fall outward to a degree, flopping in disaster. We experienced no such non-sense. The roof supports did just fine.


Although we came to find that the horizontal supports are incredibly light, we would eventually remove all but two of them as we plan to resolve any vibrations on the mainhoop and roofbars in a lighter weight fashion.
 
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