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Hey guys I wanna Targa Top My MX.

I understand The structural integrity will got to S*** so i will need to convert the frame to a Convertible style cars frame.

Any Thoughts

Give up now. <- my thoughts

You'll never complete it. You can't just "convert to convertible frame". Its not that simple.


Plus the money and fabrication skills... can you weld? No? Then for sure never.

Ryan wrote:Give up now. <- my thoughts

You'll never complete it. You can't just "convert to convertible frame". Its not that simple.


Plus the money and fabrication skills... can you weld? No? Then for sure never.

Actually i Can weld, i would need to get more practice, but I do have a full frame shop at my disposal and a bodyshop. My Family is in the Buisness.

IMO.. waste of time and money
Is a stock sunroof not good enough for ya!?

Plus I can only imagine the chances of something like that leaking.

It can be done.

I agree with Ryan and Hoodzy that it'd be a sh!tload of work, but if you're willing to do it, it'd be an interesting project.

However, before even thinking about it, I'd try to find an engineer, who could calculate the kind of reinforcement you need, especially in the roof area, so you can have the degree of rigidity you need, without adding a ton of material.
Definitely a complicated project. Be ready to spend lots of time, and a big chunk of money. IMO, it'd be much easier just to make it a convertible.

Anyway, if you do it, post pics.

I dunno about the amount of work, but I think it would look super F-ing awesome. If it were me I would try to buy a car with T-tops so I could do some good research and then buy a spare MX roof to cut and weld on. I think the MX is a funny candidate though b/c it has the upper window trim on the door and not the body. You might have to cut it off the doors, space it properly and then weld it to the roof. Then cut for the T-tops with the trim on the top... I dunno, but it would be wierd.

Its the bending moment. Your car will sag like a banana. If you cut the roof at all your frame rails will be under HUGE stress and once you open the door, it probably won't close again. You'd need to weld BEEFY C channels over the stock rails, maybe even I beams in place of them. You'd need to beef them up righ until you're under each set of wheels.

A beefy, permanent roll cage would also help, especially to hold up the wind shield, which would also likely fold down on your head at highway speed.

Perhaps build a big solid U that connects the front and rear strut towers, and goes through the rocker or something.

Ryan, you'd be surprised on how beefy these little cars are. When I cut the roof of my GS, I jumped around in it and all sorts of stuff. It didn't sag one bit from what I could tell (could open/close doors fine). I had to cut the windshield frame almost completely off in order to bend it flat.

The actual frame rails consisted of like 3 different layers making it about 3/8 in thick or more. I'm not saying it won't need re-enforcement, but you underestimate it a tad.

If that car ran, I DEFINITELY would have drove it around with the top off and not be worried about it folding up on me.

don't forget that we have frames around the windows on our doors... I have pics I can post of a targa mx-3 if you want to see.

Mooneggs wrote:don't forget that we have frames around the windows on our doors... I have pics I can post of a targa mx-3 if you want to see.

Sweet Lets See!

Jumping in the car is different than cornering/braking, bumps.

Our suspension spring rates are in the order of 600lbs/in, and we have 3-6 inches of travel... you do the math. The only structural member left is the rail, and its strength is a function of its height cubed times its width, so its lacking in height is the major downfall. The structural height of the car with a roof is over a metre, now its 1/20th that, and the difference is cubed.

Yep. I agree with Ryan, though I was thinking more of a tubular approach. I think with a properly designed cage, and a subframe structure, the car could be stiffened without making it heavier than a Cadlillac in the process.
But that's only half the work. As strong as the MX is, its roof is notoriously flimsy. Being that the plan is to keep it (or part of it) in place, he'd have to build some strong ribs into it, so it won't deform. Add to that the need to reinforce the windshield frame, the panel(s) you plan to make removable, the need to make a frame so it won't leak, the mods to the windows... It IS a ton of work.
I'm not saying it's not worth it. I think it'd be sick. I'm just saying it'd take some major modification, and some major engineering, if you want to make it durable, and at the same time you want it to still look like an MX-3 (remember the guy that was trying to sell his RWD MX-3 last year, with the 1 ft. tall iron tunnel between the seats? )

Mooneggs wrote:don't forget that we have frames around the windows on our doors... I have pics I can post of a targa mx-3 if you want to see.

Exactly. That's part of the equation to getting it to look good.

Ya, there's been a few Targa Mx-3's, I think maybe 2 or 3 of them since the beginnig of time. I think I've got pics of them somewhere too, but they still don't look 100% right, mostly because of the reinforcements added to the roof.

OMG some of you guys are way over thinking this... Just like AWD swap. time and money, before i did this swap all anyone could say is it cant be done, waist of time, the chassis wont hold up, the cars not made for AWD..... on and on and on

All you have to do is cross brace the under chassis and it will not flex or in some cases you just weld larger rails down the uni-body on top of the existing. its not hard, folks have been doing this since the 30's, 40's, 50's and 60's and still doing massive modifications like it! generally known to the majority of the public as HOT RODS. the biggest challenge which I have also considered in doing this is what mooneggs said is the tops of the door frames. this is where you would have to get creative to make it look proper. if you can take a look at a Delsole targa you can get some ideas of the actual top and design. but making the doors look rite will take a little bit of work. the rest is CAKE for anyone with some fabricating experience.

i was thinking could't i just put a roll cage in it, because cutting the roof out is a major rollover safety risk, the cage would fix the added danger of rolling over in a convertable, as well as support the frame and then the door frames wouldn't look too bad because the rollcage will be there anyway.