The thing about race cars, is there is always something to do, and always areas to improve. For this build, our primary focus has been weight reduction of our mostly-stock Saab 9-5’s parts. Starting out with a ~3,500 lbs luxury sedan has been tough, but we’re continually finding ways of reducing weight by removing/replacing Saab parts and materials, and getting creative with making that happen. Here’s how we removed the Saab’s sunroof to make that happen.
Removing the Sunroof
A factory glass sunroof presents both a weight and safety concern for dedicated race cars, and was one of those spots that required a little creativity. The simplest solution is to cut an oversized plate of aluminum and rivet that to the roof. It’s extremely effective, and extremely crude, but can likely be built in a couple hours and let’s you move on to the next task. While our Saab 9-5 isn’t a show car, there’s nothing wrong with incorporating a little aesthetic into the customized parts!
Our method of creating an aluminum ‘plug’ required tracing the hole, cutting and shaping the aluminum for the curvature of the roof, and then mounting that to the body. All relatively easy to say, but the body only has tabs on three out of the four sides of the sunroof opening, and a significant depth from the roofline. Once we decided on angle aluminum for the sides, we could profile it to the curves, drill and rivet to the body, and turn our attention to the rear. By mounting our own tabs to the roof, we could measure the depth and material thicknesses required to get the aluminum to sit flush along the rear. Fit, refit, trim some aluminum, tweak the mounts, fit, etc.
After a bit of fiddling we got it sitting and mounted nicely and were able to work on sealing up the slight gap.
Strangely enough, after looking around on several forums trying to find the most suitable sealant, windshield urethane seemed to be the most recommended product to use. A quick trip to the local auto glass shop had us walking away with a good-sized tube for $10. NOTE: In hindsight I wish I had spent a little more time smoothing out the urethane with solvent before it cured. The little bit that I did smooth did a great job of turning the large bead into more of a hump. Either way, it will need a little more cleanup before the Saab 9-5’s body can get painted, so we can maintain the ‘aesthetic’ we were after!
Removing the Wires from Behind the 9-5’s Dash
While we currently don’t need a roll cage for the time attack and rally events we’re competing in, it’s in the books for next season. In anticipation of that we decided it was a good idea to simplify a lot of the wiring in the car. Like any manufacturer, Saab wires all their vehicles for every factory option, and simply installs whatever featured parts are ordered or leaves the wiring in place. These extra wires really complicate diagnosis, add weight, and make it difficult to remove all the wiring when the time to install a cage does come. Combined with the stock Saab parts we removed including stereo system and airbags, there was a lot of excess wire.
As with Jordan Pagano’s experience with the eEuroparts’ Saab 9-3 racecar build, the dash was a lot more difficult to remove than expected, but once free, it exposed all the wiring harnesses we needed to cut into and pull wires from. Simply cutting the wires creates a very high risk of short circuits, and therefore fire, or blowing a critical fuse mid race. The best practice for removing wiring is to trace it back to its source, which is typically either the fuse box or the relay box. The fun begins when there is a plug, a joint, or some other chance of making a mistake of which wire to cut or remove. Because then you have to figure out what wire is supposed to connect to the parts you’re removing, if that fuse was supposed to stay or not, and which set of twisted brown/white wires you didn’t mean to cut. More on that next time.