OK, we love Mother Nature as much as the next gearhead, but sometimes a plan to preserve the environment can cause more harm than good to our cars. At first it seems like a great idea, (like using food to make fuel), but then the law of unintended consequences kicks in and you're left with another problem to deal with.
Such is the case with the roof hoop on later fourth-gen Camaros. Sometime in the late '90s, or so the story goes, GM switched to a new more environmentally friendly primer and adhesive to bond the composite hoop panel to the metal hoop. Over time it caused bubbles to percolate up through the panel and blister the paint. Sand the panel down, repaint it, and a few weeks later the bubbles would be back. When this happened while the vehicle was still under warranty GM would fix it by replacing the panel. Fast forward to today and an '02 Camaro is now over 10 years old, and GM stopped selling the replacement panels years ago. This meant, until recently, Camaro owners' only option was to try and salvage one from an earlier fourth-gen, and getting one off a donor car intact is more than challenging.
Enter Mark DeLisle of 6 Liter Eater Designs (6LE Designs). He heard the cries of despair, found a new GM replacement roof panel, and created a replacement part. Now Camaro owners don't have to suffer festering boils on their roof or shuffle off to tetanus-strewn boneyards to get their fourth-gens looking good. Black Betty, our '01 project car, was suffering from a blistered roof so we ordered up a new roof panel and drove the Z28 down to Best of Show Coach Works in Escondido, California, for a little R&R.
01. This roof hoop is shared between earlier LT1-era Camaros and their later LS-powered brethren. The only difference is that the earlier Camaros used an adhesive that worked, and the later ones use an adhesive that caused major issues.
02. Here's the result of the more environmentally friendly adhesive. These bubbles are soft, and if you stick your fingernail in them, they pop and ooze. Yeah, it's a disgusting visual. The bad news is that there is no way to fix the problem besides replacing the panel and using a different adhesive. Even worse, GM stopped selling a replacement panel years ago.
03. Step one was pulling all the weatherstripping away from where the panel met the car. Like most cars, it was glued on, but there were also a few screws used.
04. With the screws gone, we could gently start pulling the rubber weatherseal out of the way. Tear it and your project will get way more expensive.
05. We then unscrewed and removed the metal weatherstrip channels from the Camaro.
06. Likewise, the T-top channel was unscrewed and then gently pried from the car. It's held in place by some GM two-sided tape, so it required a little effort, but we went easy and didn't damage the part or the tape.
07. With everything out of the way we could start persuading the panel off of the car. Getting it started was pretty hard, but using a variety of wedges and a dead-blow hammer, we were able to get the panel away from the metal support. We then started working our way up and over the hoop. Keep in mind that the small triangle piece (red arrow) is reused, so make sure not to damage it.
08. It wasn't pretty, but the further we went, the easier it got.
09. After about an hour the panel was history. While looking at the OEM panel we figured out that the bubbles seemed to be caused by whatever they smeared on the panel to help the adhesive adhere better, and not by the actual black adhesive. Still, to be on the safe side, we used a scraper to remove as much of the old adhesive as possible.
10. To protect the metal roof hoop, we used some primer to cover any areas of bare metal caused by our scraping or by the panel pulling free.
11. Here's the replacement panel from 6 Liter Eater Designs (6LE Designs). Given that GM no longer makes the replacement part, you have three choices: live with the awful looking blisters, try to pry one off of an early fourth-gen (good luck with that one), or pay $390 for this reproduction. It's molded off of a new GM piece and it's made from flexible fiberglass. And while the website said the panel was thin, we found that it was a bit thicker and sturdier than the stock panel we ripped free. 6LE Designs also offers a carbon-fiber version, and they have a solution for the hardtop guys as well.
12. Before committing to the project with adhesive, we first did a test-fit of the panel. This was done with the T-tops in place, and we found the fitment to be good. If done on a sunny day it would have been even easier as we could have sat the panel in the sun for a bit to help it conform to the metal hoop better.
13. Our friend Mike Plummer had stopped by the shop that day and was pressed into servitude since he's a glass installer and had actually done this panel replacement before. He also had some cool tools on hand for prying free the old panel as well as some adhesive he knew would hold firm and be blister free. The first step was to wipe down the bottom of the panel with some Sika activator. This will help the adhesive adhere better to the panel. If you are using another type of adhesive, like 3M fast-cure urethane (PN 08690 at Summit Racing. You'll need two tubes), then just follow the recommendations on the label.
14. One of the cool tools Mike had was this electric caulking/adhesive gun filled with Sika Titan P2G adhesive. We made sure to apply the adhesive around the entire perimeter as well as the high spots in the metal towards the middle of the metal hoop.
15. With the adhesive in place, Mike and Best of Show Coach Works owner Dick Kvamme set new 6LE Design roof panel in place.
16. Using some ridiculously large clamps and some scrap wood the guys clamped the panel in place. We couldn't get a clamp down near the bottom where the new panel meets the quarter panel so we used a screw in the area that will eventually be covered up by the small GM trim panel.
17. Once the panel's adhesive was dried the clamps were removed. It required very little bodywork to make perfectly smooth. Once prepped and primed, the Camaro was masked off and the hoop was given a few coats of GM Onyx Black DuPont Cromax Pro waterborne paint. And with that, our Camaro was looking great and bubble-free.