How Hurst Hatches Fit

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This page shows first and second design hatches as they were installed in cars. There are no instructions for putting these babies in, so look carefully when you take them out.

First Design Installed

Let's look at how these were installed. This 1978 Trans Am is wearing first design silver frames, which incidentally proves that first design was still being used during 1978 car production. Notice the nice fit at the ends of the frame. You know what holds that against the roof? Nothing!

20 clamps were used on each F-body frame. These were clamped down on a piece of steel bar stock inside the roof. The bar stock was sandwiched between the inner and outer roof in the middle and the back, which greatly increased the rigidity of what was left. In fact, NONE our Hurst-equipped junk cars has the roof caved in, while almost ALL of our Fisher-equipped cars are caved in just behind the t-tops.

The original inner roof panel had no large holes anywhere. All this was cut away at Hurst. Notice the radical cuts on each end. The installers wanted to leave a little piece of the roof rail, but they hacked away a large area of the inner roof just next to it, apparently to get the last screw in. The radical cuts along the front of the roof (where the sunvisor would be) is because the separation between the roof panels was wide in the front, so you could not pinch the spacer between them.

The clip at right is the only kind I have ever seen on a Trans Am. The Hurst manual shows that there was an earlier design, but these may have been used only on G-bodies.

Front of the frame shows some of the wild cutting away of the inner roof. They just barely left enough meat to reinstall the sunvisors.

Also, you can see how that bar stock mounted. Notice that it disappears between the roof panels as it bends away from the windshield here.

Same here, they cut out a triangle of material next to the roof rail and seat belt reel. All the cars I've looked at had this feature. Apparently it was to fit the last clamp in. Here you can really see that there is nothing holding the end of the frame down tight against the roof.
The corner photos (right and below) show how the roof rail weatherstripping channel was cut away and did not actually connect to the top frame. The void between these two is filled with weatherstripping foam and glue. The top weatherstripping was sort of floating here, although it was designed to be attached to the roof rail with the inner molding screw (the same one that the t-top clamps hit)
The roof rail weatherstipping channel was cut by hand at Hurst (apparently with tin snips). This photo shows that the rear corner piece was not modified. The roof rail channel was cut so short in the back that the corner piece almost covered it completely.

1rst and 2nd Design Differences

Water leaking was the main reason for the redesign and recall. The 2nd design's major change was a much wider roof weatherstrip. Recalled F-bodies kept their old hatches, but the G-bodies got new hatches with no frame around the glass. The G-body second design went into production on new cars built after December 17, 1976. I have not been able to determine whether or when 2nd design hatches went into production on new Trans Ams.
This photo of recalled (left) vs. unrecalled (right) Trans Am t-tops shows the only difference (a little tab on the weatherstrip)
This shows Trans Am designs 1 and 2 stacked up, to show (I hope) that they are the same.
This picture shows the frameless hatches used on the 2nd design Grand Prix. There was a recall on the 75-up G-bodies to install these. The Ames Firebird catalog incorrectly states they can be used to I.D. 2nd design installations, but they weren't used on Firebirds at all. Note the brown tint color. This color glass was used on F-bodies.
Unexciting shot of the 2nd design weatherstripping
East Coast T-tops guy told me the angle here may be a bit different between generations.
Comparison of 1rst and 2nd design frames, showing the added features. 2nd design has a reinforcing plate at the bend and an aluminum casting to hold the interior trim and give the t-top something to clamp against.

1rst design frame ends depended on what was left of the original roof rail, and didn't have much structure at all. You can also see one of the 1rst design clamps, which weren't used on the 2nd design. They are somewhat prone to get loose from the roof on the end.

These two photos show the difference in the frame cross sections. The 2nd design (bottom) has an obviously wider open channel at its lowest point. This allows room for rain to flow away. The gasketing that goes on this looks a lot like Fisher t-tops.

These frames are both aluminum extrusions that were formed into a U-shape that followed the contours of the roof. Part of the extrusion was cut away here on the end. These are obviously hand made and I suppose some hand fitting was required to put them in.

In fact, Jeff at East Coast T-tops told me that when installing Hurst frames, you should position them to match the hatch to the rolled-up window glass. If the frame hangs over, you can grind it off. Don't assume that lining up the edge of the frame to the edge of the roof will fit properly.


2nd design frames installed

The two photos at right and below show the 2nd frame installed in the car. Roof cutting was almost identical, with the exception that the roof rail was cut away from the corners about an inch. Note the wild gash at the front, which barely leaves metal for the sunvisor attachment.

You will note that the hardware used to attach second design frames is totally different. There are no separate clamps. Instead, clamping screws are set in a few long bars riveted to the frame.

Rear of 2nd design frame. Note the triangle of metal cut away next to the seat belts.This is almost identical to the first design shown above.
This image compares the cuts on first and second design roof rails.
The corners of the second design had a transition from the new wide weatherstripping to a thin profile almost identical to the first design. The was necessary to allow the original T-tops to fit in.
Here's that corner from another angle showing the fittings used to keep everything in place. The bracket on the right is exactly at the spot where the weatherstripping narrows.
The other corner from a third angle, looking straight up. This shows how the weatherstripping was makes its transition to the roof rail. Even on the second design, this was installed mostly in thin air.
One of the best-liked features of the 2nd design is this molding that holds up the headliner. There are two version of this. I assume the long version (below) is earlier, because I suspect it was superceded due to problems with the ends.

The short molding (below) looks like the long molding with the ends sawed off, but it came that way. The small pieces pictured above are used with the shorter molding. For more details on this version of the molding, see our recall page.

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