Putting the VW Type 3 body on the Mazda Miata chassis - Project Frankenwagon, Part 5

Submitted by Dan on Mon, 02/04/2019 - 16:49

Yesterday was perfect. Everything went to plan beautifully. Even when things didn't go to plan, like how my new engine hoist was too tall to lift it from inside the body, I adjusted and came up with a solution pretty quickly. Or how the hoist was also too tall for the legs to slide under the Miata, I just had to throw some wooden blocks under the tires. 

Here was the order of events:

  1. cut the part of the body that I needed off (the window sills, roof, cowl, door sills, trunk lid area, etc.), leaving the rusty crud that I don't need (rear inner fenders, rockers panels, firewall, etc)
  2. Lift it up and off of the old chassis, move it to the right (behind my wife's parked car, who thankfully didn't need to go anywhere that day), and set it on the ground. 
  3. Move my 4Runner that is parked in the yard over to the driveway entrance, out of the way
  4. Roll the old VW chassis to where the 4Runner was parked in the yard (had to use the 4Runner to push it through the soft/muddy ground)
  5. Roll the Miata out of the garage, down the little incline, and stop it next to the Type 3 body. I had to ask my wife to sit on it and use the parking brake lever to stop it. She had fun though.
  6. Pick the Type 3 body back up and drop it down onto the Miata.
  7. Get the Miata+Type 3 Frankenwagon up the little incline and back into the garage. I was going to use a come-along winch but my chain AND my strap was instead being used to lift the body (was originally going to just use one short piece of chain) so I had to think of something else. I could have bumped/pushed it up with my 4Runner but the rear of the Type 3 body was not secured to the chassis in any way and it surely would have damaged it. So the only other thing to do was start up the Miata and drive it up and into the garage. That was fun! 
  8. ...
  9. Profit!

Why did I cut it off the old VW chassis instead of unbolt it? That fact that it unbolts from the floorpan was one of the selling points of using a VW over another type of vehicle. 

Well I was getting ready to unbolt it and pull it off the chassis, like normal, then cutting off what wasn't needed. But there's so much rust that needs to be cut out - like above the rear inner fenders, the rockers inside and out (everything but the sill), firewall, cargo area, etc. - that I realized I can just make those cuts now and leave those rusty parts attached to the chassis. Which I'm just going to sell for scrap to get it off my property as quick as possible So I don't have to park my DD in the yard anymore. It's turning into a mud hole and my wife, umm, would rather it not be a mud hole. 

I'm for sure keeping the bits of metal that the fenders bolt to, and the front nose area where the bumpers bolt to. But I'll have to make new bumper bolt points as they're too rusty and the PO tried to repair it with fiberglass. Yeah, the front bumpers where held on with fiberglass! And of course it will need to be tied into the miata front chassis rails. 

So after cutting off the body and lifting it off the old frame/floorpan/chassis, I rolled the Miata chassis down the driveway and next to it. I had to raise it up off the ground a little with some 2x4s becaues the legs of the engine hoist were too tall to roll under the Miata.

frankenwagon miata chassis body swapped with vw volkswagon type 3 squareback

I just used my best judgment to decide where to place the braces inside the body. I was limited though because I knew that I couldn't put one too low, like on the lower door sill like I wanted, because it would have intersected with the Miata's rockers. And I had to watch out for the seat belt towers as well as the bolt points for the Miata dashboard, the two diagonal pieces came very very close to hitting those points, I was lucky. I used 1x1 gauge, some 1" angle iron 1/8" thick, and some 1" black pipe, just whatever I could find. At first I just tacked two in there for the doors. Then decided I could add another few going across. Then I just went crazy with it and added all the metal I could find in the scrap bin. Then I realized I could lift the body up from this structure, so I went over all the tack welds with full welds. It will be a much bigger pain to remove the braces but oh well.

But when it came time to lift it up the next day, the engine hoist (which I assembled that morning) was too tall to lift it from inside the body so I had to change plans and lift it from the outside, but I figured out a slightly wacky solution in which the long strap wrapped around the brace structure in the middle, went out the back, and then met the chain - which was wrapped around the roof over the door opening. When I started lifting, the chain tightened and squeezed the roof somewhat, and pinched the rain gutters (that's an easy fix I think). So not the best, but I was in a hurry as I was loosing day light and the super bowl was starting.

frankenwagon miata chassis body swapped with vw volkswagon type 3 squareback

frankenwagon miata chassis body swapped with vw volkswagon type 3 squareback

frankenwagon miata chassis body swapped with vw volkswagon type 3 squareback

frankenwagon miata chassis body swapped with vw volkswagon type 3 squareback

The body is just resting on top of the Miata at the moment, just so I could get it into the garage and out of the weather (and where I can grind away without pissing off the neighbors). I could have picked it up, with the help of two or three other guys, and carried it into the garage, but that wouldn't have worked because the garage ceiling is too low! 

Now that it's in the garage, I'll need to lift it as high as it will go so I can do all the things I should have done before dropping it onto the Miata but I didn't have enough daylight. Mainly, clean up all the cuts and remove paint where I'll need to weld. And maybe even figure out a wiper setup while I still have easy access.

The body will need to be moved a few inches forward and a few inches down. There's a pinch point at where the inside of the A pillar intersects with the Miata cowl area. I expected that but it's actually not too bad and I think I can, umm, adjust it with a hammer. 

It looks like the VW hood hinges might work, but that could change as I move the body down. 

I still need to cut the Type 3 "nose" off, as well as the strips of metal that the fenders bolt to. And I'll need to use the front fenders to determine where the body sits on the Miata front to back. The rear fenders will likely need to be rolled/pulled/pushed/stretched/whatever but maybe I'll put one on there for fun to see what happens. 

I've very pleased with the way it is fitting so far!

Part 6: Welding the body to the chassis