BUILD-OFF CHALLENGE: Tygaboy's '75 LS3, It seemed a good idea at the time... Options

[tygaboy]

One for @Andyrew : The curvy template tool put to use, once again!

Rough measurements suggest this amount of roll suits the entire X brace; both the "side bars" that tie the targa bar to the windshield, as well as the X brace.

In my design, the skin is really only serving to close things up.

[Andyrew]

Love that tool (IMG:style_emoticons/default/smile.gif)

Is the bar design going to protrude into the "helmet" space at all?

[tygaboy]

Love that tool (IMG:style_emoticons/default/smile.gif)

Is the bar design going to protrude into the "helmet" space at all?

@Andyrew - No. Well, let's say "not hardly much." The curve will keep the tubing (1.25" DOM) tucked right up against the roof. Kinda like in the pic @sixnotfour previously posted. But my X will go from corner to corner, unless test sitting and fitting show an issue.

[tygaboy]

Rough fitting the first side rail bar. At the front, I'll make two small plates - one for each side of the tube that welds to the upper and lower lips of the windshield frame and then to the tube.

I still have some trimming/fitting of the notch at the rear to be sure the tube fits under the roof skin.

[Mueller]

Rough fitting the first side rail bar. At the front, I'll make two small plates - one for each side of the tube that welds to the upper and lower lips of the windshield frame and then to the tube.

I still have some trimming/fitting of the notch at the rear to be sure the tube fits under the roof skin.

that is crazy cool.

[Andyrew]

Oooh that's sexy.....

[horizontally-opposed]

Hmm....wrong thread. (IMG:style_emoticons/default/wink.gif)

[Cairo94507]

That 914 will go down the road like a solid billet of aluminum. That car is going to be wicked fun. (IMG:style_emoticons/default/beerchug.gif)

[sixnotfour]

That 914 will go down the road like a solid billet of aluminum. That car is going to be wicked fun. (IMG:style_emoticons/default/beerchug.gif)

(IMG:style_emoticons/default/beerchug.gif) (IMG:style_emoticons/default/cheer.gif) (IMG:style_emoticons/default/driving.gif) (IMG:style_emoticons/default/popcorn[1].gif)

[914forme]

I like the solution for the roof structure. The bars going corner to corner can become a bit of a head banger. Suggestion would be shallow channel and maybe lots of dimple dies. Or stamped panel that follows the theme of the firewall with exposed carbon sections. (IMG:style_emoticons/default/drooley.gif)

Factory GT lids just had a small raised section. I did one of these once, bonded the top to a metal cross section and DOM sides rails like you have. I found that the top got really heavy really quick, and I ditched it. Started thinking steel skin - thus the 944 section and manual latches for the sun roof. Proven design, and could be opened to vent the car during runs.

BTW, I have that roof section and great 944 manual sunroof if you need it. Also have a Ford GT 3rd brake light that needs a good home whilst you're cutting. (IMG:style_emoticons/default/poke.gif)

[tygaboy]

I like the solution for the roof structure. The bars going corner to corner can become a bit of a head banger. Suggestion would be shallow channel and maybe lots of dimple dies. Or stamped panel that follows the theme of the firewall with exposed carbon sections. (IMG:style_emoticons/default/drooley.gif)

Factory GT lids just had a small raised section. I did one of these once, bonded the top to a metal cross section and DOM sides rails like you have. I found that the top got really heavy really quick, and I ditched it. Started thinking steel skin - thus the 944 section and manual latches for the sun roof. Proven design, and could be opened to vent the car during runs.

BTW, I have that roof section and great 944 manual sunroof if you need it. Also have a Ford GT 3rd brake light that needs a good home whilst you're cutting. (IMG:style_emoticons/default/poke.gif)

@914forme - Thanks for sharing your experiences with roof mods! Sacrilegious though it may be, weight isn't my primary concern. And you know me - I'll likely change the design as I go.
I was noodling on the cross braces, too. I have an idea I think you'll like! More as I get to cutting some material.
And thanks for the reminder about a 3rd brake light! I'd overlooked that completely!
I'll PM you on the GT light. I have a part I think you may want to swap for it...

[tygaboy]

Change of plan #1: I've decided to bond on a gutted stock roof. This solution comes complete with seal rails already in the correct spot and a virtual guarantee that it'll look stock to all but the most attentive observers.
Plus it saves me time fabbing the roof skin.

I'm running early doors so I went with an early roof as I understand mismatching early/late doors and roofs = issues with the window-to-roof seals.

I'm curious in that, near as I can tell from places like 914 Rubber, the available replacement seals are all "late style". Is it the shape of the seal channel or something?
Anyone know the details on this?

But for now: I thought our roofs were fiberglass. I didn't know they had a core in the header! This is my "learn something new everyday" item for today.

Anyway, here I've clearanced the header for the side bars. I'll add a couple layers of fiberglass over these areas.

[tygaboy]

I also quickly realized that running the stock roof meant I'd need to move the side bars inward a bit to clear the inner portion of the roof. So I did that and ended up with what I think is a nice fit.

The side bars sit up in the roof such that there's no head/helmet issue at all.

[tygaboy]

One impact of this design approach is that without the windshield-to-roof seal, the roof is able to slide forward about 1/4". This is the "attentive observer" item mentioned earlier.

I used some ratchet straps to help hold the roof in it's new forward location. As mentioned, I plan to paint the roof black so this is sorta what it'll look like once it's bonded on.

I plan to seal the joint but leave this area looking as much like this as possible. I won't try and fill that joint but rather leverage the bonding adhesive and perhaps a tiny amount of sealer to prevent leaking. Ideally, the roof will still look as though it can be removed.

[tygaboy]

It's a bit hard to see but one other area that will need a bit of fab is across the rear of the targa bar to the roof. With the seal that normally fits there now gone, there's a gap. I'll create a piece that welds to the targa bar and has some sort of flange to which the roof will bond.

On to the X-braces! (IMG:style_emoticons/default/sawzall-smiley.gif) (IMG:style_emoticons/default/smash.gif)

[tygaboy]

In looking at that last pic, I realized I'm only a couple days away from permanently removing the door braces! Boy, oh boy, talk about a MAJOR milestone... (IMG:style_emoticons/default/piratenanner.gif)

[tygaboy]

Initial fitting of the outer rail-to-windshield plates. Both sides are tacked in, ready for final trimming and welding.

[tygaboy]

I need to figure out how I want to close up the gap at the back of the targa bar so I started on a piece to help me get a feel for the shape I'll need.

I used a piece of 20ga, bent it to 90 degrees then went at it with the shrinker/stretcher.

And of course it curves both directions... But this was either an easy piece or I'm getting faster at working metal. It only took about 15 mins to get to this point.

And the clamps aren't adding much pressure, just holding things in place. The piece sits almost perfectly on the targa bar.

[Cairo94507]

(IMG:style_emoticons/default/popcorn[1].gif) (IMG:style_emoticons/default/beerchug.gif) Jesus, I love this build.

[Andyrew]

Wow thats a major design change! Gives it more of a sleeper look than an outlaw or 916 look.

Certainly be much faster than making a roof! Im curious. Are you going to make a couple of wind holes in the rear of the top to allow for some pressure relief while the windows are down?

I've always wondered if people with GOOD seals had that issue.