Adding XR7-G exhaust cut-outs to a 1967 or 1968 Mercury Cougar

There’s one detail of the 1967 Cougar that always bothered me — the way the exhaust sits under the rear valance.

Originally, I believe the Cougar had turn-down exhaust tips that were somewhat hidden, but through the years almost everyone has run the exhaust under the valance, both to keep fumes out of the car and to give it more of a muscle car style.

However, in 1968, the XR7-G package boasted exhaust cut-outs with chrome trim rings, which to me, makes the back end of the car look much classier. Since I was undertaking body work to prep my car for paint, I decided to retrofit the XR7-G trim rings and exhaust tips onto my 1967 standard.

I ordered the trim from West Coast Classic Cougar. While it seems like a high quality reproduction part, all repro parts have their quirks. The odd thing I found about these trim rings is that one mounting peg is a different size. With pegs facing up, the right peg is a size smaller than the center and left pegs. This really doesn’t matter except that the spring nuts supplied with the rings are all the same size. They fit tightly on the center and left pegs, but fall right off the right peg. You will have to source a smaller size spring nut to mount them.

One good part about these trim rings is that they are symmetrical, so you can easily flip them over to trace the pattern onto your valance.

Step one was to remove the rear bumper guards and brackets. Not all Cougars had the bumper guard option, but if yours had them, and you are removing them, don’t throw them away. Each bumper guard has a core value of $50 and the brackets trade for about $100 a pair.

I got varying measurements from XR7-G owners as to how far apart the cut-outs should be spaced. I found my exhaust pipes lined up right under the top mounting holes for the bumper guards, so I used those to mark the centerline for my cutouts. I’m not trying to pass off my car as an XR7-G, so I would much rather have good exhaust alignment than perfect factory specifications. If you’re measuring from the bottom edge of the valance, on mine the outside edge cuts were exactly 8″ off the end-curves of the valance.

I could have probably cut the entire shape out with a dremel, but on the Classic Cougar Community forum, a member suggested using aviation tin snips to quickly do the bulk of the cutting and then just clean up the edges with a dremel. I decided to give that a shot — plus it gave me an excuse to buy some nice tin snips.

The only downside to the tin snips was the bend it puts in the lower portion of the valance, but it was easily tapped straight with a hammer and a dolly. I finished cutting and cleaned the edges up with a dremel.

Drilling the mounting holes precisely enough to get the bottom edges to line up perfectly straight was the trickiest part. Using good metal bits and stepping up the hole sizes made it much easier. In the end, I had to oversize a few holes to give the trim some adjustability.

My exhaust hangers were adjusted all the way down to get the pipes under my rear valance, so it was easy enough to raise them up to move the exhaust tips into the new cut-outs. However, it wouldn’t be a DIY project without an unexpected challenge. I didn’t notice that the backside of one hanger bolt had two nuts on it, and I twisted off the head trying to tighten it back up.

Thankfully I had a replacement nut and bolt rolling around in my toolbox, so it only caused a short delay.

The old rusty exhaust tips already look better poking through the new cut-outs. It will look really great when I have the larger, shinier XR7-G tips welded onto the system.

Once I had proof of concept and good measurements, I ran through the entire process again on the reproduction rear valance that I’m prepping to install before I paint the car.

I think I may toss the flat nuts and use speed nuts to install the trim rings, so that they are easier to unscrew if I want to repeatedly install and remove them while I continue doing body work and changing things on the car.

So now that I have the XR7-G exhaust trim, the real question is whether or not I should add the XR7-G hood scoop!

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Learning to Paint: Cut and polish

I only had an 18-hour window to apply clear coat after the last coat of color to ensure adhesion. However, I needed to wait a minimum of 24 hours after spraying clear before I could start the cut and polish process.

The clear coat brought out the color of the black cherry paint, but it had noticeable texture. I also had two runs on the air cleaner lid, which were easy to see, but very hard to photograph.

While I had plenty of lower grit sandpaper for paint prep, I hadn’t thought about the grits required for the polishing process. I made a run to my local True Value, but the finest grit they carried was 320. Thankfully O’Reilly’s had a full section of polishing supplies, so I purchased 1000, 2000, 3000, and some polishing compound.

Because I needed to remove the two runs in the clear, I started the process with 600 grit dry sanding. Once I got a cross hatch pattern across the entire surface, I rinsed the lid and sanded with 600 grit wet. I did another rinse, then sanded 1000 grit wet. Then I went to 2000 grit wet. Then I used my random orbital sander for 3000 grit wet. Then I finished the lid with a buffer and polishing compound.

The difference in depth, shine and texture was amazing. I still had some unwanted texture in the grooves, so I actually repeated the entire 600 wet through buffing again. The lid looked fantastic.

I was actually using the air cleaner before this project started, so I was anxious to get it back on the car. I tackled the bottom of the assembly next. I decided to forego the 600 dry sanding portion and just start with the 600 wet. By the time I finished, I could barely move my arms. I don’t think I’ve done this much intense sanding and polishing in my entire life.

I got the air cleaner back on the car, and I decided to tackle the valve covers and oil pan later.

The biggest lesson learned is that preparation is everything. My paint is smooth, but if you look down into it, you can see that the surface of the metal is not. There was quite a bit of pitting in these old rusted parts, and I should have done more sanding before the primer and more coats of primer to smooth it all out before the color coat.

Here’s a side-by-side example of the difference the cut and polish makes.

I do have confidence that I can tackle painting the entire car with the turbine sprayer and get an acceptable result. However, unless I fix some of the underlying alignment and body issues first, it’s just putting lipstick on a pig.

Learning to Paint: Applying clear coat

I spent an entire morning sanding down the color coat I had applied the day before to remove all of the cardboard and plastic that had stuck to the paint when I flipped various pieces before they had cured. I had previously sanded it all with 400 grit, but this time I wet sanded with 600 grit to get a better finish.

I dug out some wire hangers and worked out a new tactic for the my second attempt at color.

I mixed, re-mixed, and then mixed the color again hoping it would be more red this time around. It looked the same as it had before.

Once I had two nice coats of color back onto the parts, I let them cure for an hour, and I prepped for clear coat.

The Eastwood Clear mixes 2:1, so it’s a bit thicker than the color and base coats that mix 4:1. In the future I think I would add reducer when using it with the turbine sprayer.

The Eastwood instructions only call for two coats of clear, but the Kindig It Paint with the Pros instructions call for five coats of clear. It was going on really thick and really clouding up the air in the garage, so I quit at three coats. There really had been virtually no overspray with the base and color coats, but even using the low VOC activator in the clear coat, it was creating serious fumes. People walking their dogs along the street were coughing as they passed the house.

The first coat went on really well and made the color shine, but the second and third coats went on cloudy and had me worried. Thankfully, they dried clear.

I gave all of the parts plenty of time to cure before touching or moving them this time. I’m proud to say that after having to prime twice and shoot color twice, I got the clear right the first time.

I would have liked less texture in the final project. I think reducer would have helped. As I analyzed the parts in the light, I thought, it’s not TERRIBLE, but I wouldn’t have paid for this job. However, it can only get better after the cut and polish.

Learning to Paint: Laying down color

Before jumping to the color base coat, I decided I need to spend more time working with the gun and attempt the primer again. I diluted it 3:1 instead of 4:1 and made sure I had the paint feed all the way open. I got slightly better coverage, but unfortunately there was still too much texture to the spray.

At left is my second attempt at primer, which still has noticeable texture. At right is a valve cover sanded with 400 grit.

Frustrated, I turned to the internet. After watching a half-dozen videos, it became apparent that to get good results with the turbine sprayer, you HAVE to use the pressure cup. I was using a PPS 2.0 disposable cup liner system. There is actually a 3M PPS pressure cup that uses the disposable liners, but I only had the gravity feed cup. I decided to use the stainless pressure cup that came with the gun for the color round. It made a HUGE difference.

I mixed up the Bonneville Black Cherry. I was really excited about this color, and I have debated whether or not I should paint the entire car with it.

The paint looked very black, but as I stirred, the metallic red began to appear. However, as I sprayed it on, it looked black with a hint of plum. I did some parts with what I would deem a regular coating and some I went heavier to see if it would affect the color at all. However, as it dried it seemed to become more of a bronze champagne? I’m not sure how to describe it. The photos below required the camera exposure to be pumped up to see the color because without direct sunlight, it looks more or less black.

I learned some important lessons this round beyond just the fact that I have to use the pressure cups.

Lesson 1: Laying the paint on thicker did not improve the color, it just caused solvent popping.

Lesson 2: I’ve got to stop painting on a table. The first round of paint keeps drying on the plastic sheet, then it cracks off and blows dust up onto the things I’m painting.

Lesson 3: If I have to flip something I’m painting, give it extra EXTRA time to cure before flipping or it just screws up the paint I’ve already sprayed.

Lesson 4: Don’t remove the coveralls until after you clean the gun or you will probably splash thinned paint droplets all over your clothes.

The valve covers, which were stacked higher than everything else and don’t require flipping were the only pieces that came out “good.” There’s one very small run on one of them, but I can’t decide if it’s worth fixing or not. The oil pan was great until I went over it with a SUPER thick experimental coat to see if I could get more of the red color to come out. The red did show while I was spraying it. It then dried the same color as everything else but with lots of bubbles from solvent popping. I think I’ll re-sand and re-spray it. The air cleaner lid and base both fell victim to having cardboard stick to the bottom side while I painted the top. The snorkel was sitting right on the plastic, and it has plastic coating the entire bottom side now.

I will definitely find a way to hang my parts to do another color coat before I move on to clear coat.

One thing I have decided, I do not want my entire car painted Bonneville Black Cherry. I will not order the paint for my car online. I need to find a local shop where I can lay my eyes on the real colors before I commit to spraying the car with it.