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cutting roof off unibody wagon

12K views 29 replies 12 participants last post by  PapaG 
#1 ·
I need a practical vehicle that does not exist. AWD, good mpg and a bed since a car is useless to me. Does not exist I kno. But cut the roof off a Subaru outback wagon, cut and section a small truck bed fenderwells and floor. Figure out a rear window and cab wall that looks right and its there.. In theory.... Will it fold up from no structure, or would the bed structure and rear cab wall be sufficient? I want it to have 500 lbs capacity, which is conservative as the cars rated for 900 lbs, so 400 for driver and passanger. Figuring it will be lighter without rear top and interiors
 
#4 ·
If I get lucky enough, I could find a front end wrecked Subaru Baja which is the factory truck version of the outback with 4drs and a sorry excuse for a bed, and use its rear cab wall. But they were low production and most have gotten rebuilt if they were wrecked.. If it works out tho, I will import an aussie or jdm dual range trans
 
#5 ·
. When doing something not done before, you need to do your own testing... cut the top off and support the vehicle in the middle... and then by where the wheels mount... and measure how much sag you get in the middle... same for body torque/twist, jack up body by a corner and see how much it twists... add subframe connectors and braces as needed to get it reasonable...


. I'd start with an AWD Hemi Chrysler 300 Magnum wagon... but it might not get the MPG you're looking for...
 
#6 ·
Magnum would be cool, but it would break the bank. The u pull it has $100 beds and $20 rear windows. They would give me the cab wall for $.10 per pound, and the car I can find a good one with bad engine for $800 or less and swap in an EJ22e for a couple hundred. Instead of the rod knocking overheating EJ25D the outbacks came with. Plus I want a 5spd.. Subaru cars are like Legos. Everything fits as long as you keep the heads and intake within the generation the car came from.
 
#10 ·
I could do that. They are actually rated to tow 1,500 lbs with a class 1 hitch. But, I think id rather have the vehicle. As a single unit.. I have a 2011 F250 which is my current daily, but I want to keep miles off it, so I want to leave it for big stuff only. I had a 1999 Legacy Sus which was an early Outback sedan, and with the 2.2 swap I was getting 27 mpg.
 
#12 ·
I almost bought a Cutlass Cruiser Custom with a 307 olds. Owner said it could get 30 mpg but he got pissed one day and took a hammer to the cluster and was selling mainly for a derby car.. I so wanted to buy it and dump a 455 in it. Clean title and all but smashed up dash I could not get past.. Subaru is Awd also. Need that for the ny winter climate
 
#16 ·
Doing all of this cutting and swapping to a station wagon gains you what over an S10 pickup with a 2.8 and a five speed? A lot of work and not even a 1/4 of the load carrying capacity? Buy an S10 and be done with it.
Mark
 
#17 ·
First question is.. Can it be done. Answer is yes. Is it easy.no. Reason being is the way the way uni-body structures tie together. In order to cut a uni-body car apart you have to realize that most now are not made of mild steel. The frame rails are made from hsla steels and the passenger compartment. Ie: the a-pillar b-pillar and in some the c-pillar are made from a variety of materials from hss, hsla,uhs,uhsla, cobalt and other exotic metals. No easy way to say the least Since as soon as enough heat is applied to them they are destroyed and weakened. You would have to cut after the b-pillar leaving the reinforcements inplace and build around it. then build on top of the frame rails in order to keep its strength Tieing into the b pillar reinforements. Trust me..no simple task as there still is the possbilty that it might not be square and true with the body centerline. another alternative is finding a donar full frame building body mounts to support it and using its suspension steering and engine..
 
#20 · (Edited)
Subaru did it in the 70s and 80s, and then a version from 2003-2006

The Subaru Brat and then the Subaru Baja. These were both unibodies, and the Baja was built on the Subaru Legacy outback. The same car I want to modify.. I would just buy a Baja but it has 2 knocks against it. One is the back seat and tiny bed. They have a trap door behind the seat but its not all the way across to be totally use full. Second is expensive. 3 yr production run and they are in demand. 10-16k will buy one.

I planned on adding the structure back in the form of an old truck bed inside, and tied back into the structure as the roof was. Connecting the Subaru subframes together would also be done. They have a front and rear subframe.. This will make a bed with approx 64" from cab wall to tailgate. Subarus figure was 67" cargo room with seats folded
As far as a 2.8 s10. This is the rust belt. Find me one that's not rusted out for a decent price that hasn't been restored.. Just not going to happen..
 
#22 ·
I would be open to an older 2.8 s10 4x4 or 2.9 Ranger 4x4. Since I know both are good for over 20mpg while still being 4x4.. My F250 gets close to 20 on the highway, and I kno a lifted 4.3 will use more than my F250.. The beauty of the Subaru is the perfect AWD system and balanced steering and suspension.. I also have a stockpile of parts, service manuals and special tools for them.


5 years ago, I gave $1k for my 2.5 5spd ranger which was a 1998. It got 27mpg, mint cond with 120k miles but 2wd and i could not deal with that in winter, so I sold it for $3k after i put a newer grill and lights in.
 
#23 ·
Let me approach this in a generic sense as an engineer.

If you study the difference between the body structure of even a framed convertible vs the hardtop or sedan of a particular vehicle, you'll notice that the convertible has structure that braces the sides to the floor. The roof most significantly is playing a structural role to keep the sides from bowing outward under load.

Same principle applies, only moreso with unibody. You'd improve your likelihood of success by trying to find anywhere there's structure crossing under the floor and brace the side with gussets.
 
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#25 ·
I never found the right car to complete the project before I lost ambition. all had either excessive body rust or a rusted rear subframe. Subframes fixable and Subaru sells the parts but I just did not want to deal with it.. as far as there AWD system. its available with front and rear LSD. Outback/ SUS sedans were pretty common with rear LSD. the 1999 SUS that I had was rear limited slip. and as far as lego's. it's because you can bolt the heads from any series EJ onto another series EJ and as long as you have the right intake manifold for the heads you used, the engine will fire up and run and throw no codes for the car it's in.. you can swap displacements and go from a 2.2 to a 2.5 or a 2.5 to a 2.2 and it will run fine.. suspension and rear differential are all the same between all the models to 2000 also. after that, the Legacy and Outback got different front suspension but the rear differentials actually bolt up. 1993-2015. unchanged except ratios are a little different now... There modern day Beetles really
 
#24 ·
there have been dozens of unibody cars made into utes in Australia .Most commonly they have been mercedes .
The big trick to remember is that the central tunnel is actually the main load bearing structure in the car.
I have seen this strengthened by simply adding tuber along each side to tie the cowl section to the trunk section which carries the rear diff.
If the car is a two door simply tie the upper section of the car behind the drivers area to each side to prevent the sides spreading . the front part of the roof carries the rest.
As for using the truck bed. That is a lot of effort for not much gain.
once you have the rear of the roof and the door etc off you will see that the inside structure doesn't need much strengtheneing and a few made up panels will be OK to line it with.
In your case i would contact a few dealerships and ask to see their parts catalogues .What you need to find are the INNER panels for light duty truck beds that you can use to line the body .
Heres a 1972 mercedes 280SE i am building for a customer right now.
 

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#26 ·
A 1972 merc is a tank the outback is a beer can. And its not fosters LOL.
Only Americans Drink fosters.

It does not have a strong tunnel like the merc these are completly different cars.
If you had a merc to start with it might work out ok but treally more of a show peice. Try to carry some weight and it will be over loaded in no time.

And the merc in the picks has aframe under th rear wheels and the bed is extended over the back tires on the frame.
No frame under the rear wheels and nothing was extended . The rear fenders and chassis rails are stock.
Not inside the uni body very different than a outback unibody car.

This model Mercedes is a W108 ,a full unibody design with front and rear crumple zones . these had to remain factory stock to enable registration under Australia's strict rules.
There should be no great difficulty in making the Outback into a pickup or ute. All he is doing is shortneing the rear half of the rook and a bit of thought into how the missing struture can be dupicated behind the driver seat should be easy enough.
This a W123 conversion in the USA.The obvious thing that can be seen here is that the B pillar has been built as a buttress to shift the stress pont further ..again replacng the rear of the roof that was removed.

And this is a W210 Conversion with extended rear.
 
#30 ·
A number of VW Type 111 (3) Squarebacks (station wagons have been done over the years BUT it still keeps the VW pan intact. The Type 3 uses a boxer type engine so it is flat under the bed.

Uni Bodies have been used for a long time.. We used frame connectors to tie the sub frames together. But I am not sure what the Subbie has. We used aa lot of Subbie engines in air cooled VW's

I liked the first Benz El Camino. Diesel engine would be cool.

Late model VW's Passats have a diesel engine in them. A wagon would be a cool. I could squeeze 45 MPG out of my 97 Passat TDI wagon. They have been converted into utes.

Don't let the back window throw you... They can be cut by people who know how.. But a tape measure and a good old fashion "junk" yard where you might find something that would work.

There have been Rabbit Pickup trucks stretched into 4 door trucks, so a unibody can be stretched, I would think a subbie could be cut and braced to make in to a ute type truck.... It all depends on your skill and the time(and money) you want to spend.

Good luck..
Have fun with it.
 
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