Installing a NASCAR Style Exhaust System on a Foxbody Mustang

(Narrator)>> Today on Detroit Muscle Marc works on "Project Sydewinder" giving it an aggressive exhaust system that's sure to give it a sinister sound on the track. Plus Tommy tackles the wheel tubs on the '85 Buick preparing it for some larger tires. ♪ ♪

(Tommy)>> Hey y'all, welcome to Detroit Muscle. Today we've got our '80's ladies back in the shop and we've got some pretty big plans for them. Now after getting our LS three and our new chassis up under our Buick we can finally start making some preparation for some big ole meats back under the back side of this G-body.

(Marc)>> And as for our '81 Cobra project, "Sydewinder", goes today we're gonna do the exhaust. And I know I've been teasing it for quite a while and I've hyped it up quite a bit but it's for good reason. You'll see here in just a minute.

(Tommy)>> You ready to go up?

(Marc)>> Go ahead.

Well since this is a fox body Mustang most of you probably already know that there's just about any exhaust system that you can think of available in the aftermarket for this car. Probably more than any other car that's on the road. Now you can get factory style stuff. You can get polished tips, turn downs, you can even get dumps, and systems all the way up to about three and a half inches. Now that would be easy to just click a button and order one of those kits but we don't like doing that around here. Besides we've got these three and a half inch collectors on the long tubes. That would have to be adapted to something anyway. And beside I've got something planned really special that's outside the box. Emphasis on the "side". Well here they are folks. These are boom tubes, and in case you don't know what they are this is kind of like what they run in NASCAR. It's a muffler and a tip kind of all in one. We got these from Summit Racing. What's nice about these is they have a three inch inlet here, which is nice and big but also the tip, you can just run it straight out of the side just like that or you can actually come out at an angle and then make a cut here. Now the baffles are here. You don't want to cut into those but other than that pretty much free to do whatever you want. So what I think I want to do. Get these under the car, figure out where I want them to be, and then connect the dots between my collector and the inlet. Well I've got my mufflers under the Mustang here, and as you can see I've got them in different locations but I do have them both at about a 45 degree angle because that's set. That's the way I want them to come out. That way I can make a nice long cut against the rocker panel there. But it you notice, I put them in different locations front to back. This one's further forward. It's actually really close to the transmission cross member here, and it's gonna dump out just about where the driver is over here. It's gonna be pretty loud. If you want extra cool factor and you want it super loud, that'd be a good way to go. Over here I've got it exiting back just in front of the right rear tire. It's gonna dump out behind any occupants that are in the vehicle. So it's gonna be a little quieter, not a whole lot, but what this really does is give me room here to put a mid-pipe. I can put an "X" or an "H" in here. I really want to put an "X". Besides if I come out of the "X" it might be able to just go straight into the inlet here. That's what I'm going for. So I want to go with this one right here. I just need to make sure it's not hanging down too low. So I'm gonna use the level here against the collector and that's actually almost perfectly level. So I know it's not hanging too low. That'll work just right. Now we need to connect our header back to the inlet on those new mufflers and we're gonna do that with everything you see here on the table. We got all of this from Magnaflow. It's all stainless steel and three inches in diameter. Now most of this stuff came out of one of its universal hot rod pipe kits. I didn't pull out the whole kit cause we're not gonna need much to take care of our Mustang here, but it comes with everything you need to get it installed on your car. All the bends, like a 45, 90's, 180's. These are my favorite cause you can just make a cut anywhere here to suit your needs. Something else that's important when you're installing an exhaust system is for it to be removable, and you can do that with these ball and socket joints right here. Now I want to make sure ours is removable in case we need to pull the engine, or driveshaft, or whatever to work on the car. Something they don't include in those kits but we ordered from Magnaflow as well is this smooth transition pipe, also known as an "X" for obvious reasons. This thing does have the benefit of scavenging, which is gonna give you a little extra power. It balances your exhaust system on left and right, but also for us it's cool cause it's gonna point out at that 45 degree angle, hopefully right into the inlet on those boom tubes. All right let's see how this "X" looks in here. Need to get a little space underneath that driveshaft loop. Oh yeah, that's gonna go like straight into that muffler. That's gonna be good, and it looks like there's room here to make a bend up here to under that loop on that cross member. I just need to get a measurement here. Get a couple of pieces cut. All right, looks like eight and a half will do it. ♪ ♪ [ saw cutting metal ] ♪ ♪

(Marc)>> Let's get this under here and get it fit. Slides into there nice. That's cool! That looks really good. Now I just need to get this muffler moved back, measuring and cut that piece that needs to go there, and before you know it we're gonna have an exhaust system on our Mustang. Don't go anywhere!

(Narrator)>> Don't go away, things begin to heat up as Marc burns in the finishing welds on "Sydewinder's" elaborate exhaust system.

(Marc)>> Yep, that looks good right there. Hey folks welcome back. We're plugging away on the exhaust system on our '81 Cobra, "Project Sydewinder", and we're in the home stretch here. We're installing some really cool side exit boom tubes and we've got them all mocked up from the "X" back. Now what we need to do is connect the collector to the inlet of the "X" here. The problem is the collector's three and a half inch and the "X" is three inch in diameter. So rather than just necking it back down three I'd rather modify that header. Thankfully for us these headers have a slip fit merge collector. At the bench we'll use the three inch ball side of our joint to decide where we need to make the cut on the bell of the collector. ♪ ♪ And with it marked we'll also mark where we want to cut the excess off the joint. ♪ ♪ [ saw cutting metal ]

(Marc)>> Over at the band saw we can make our cuts and clean up the edges. [ metal grinding ]

(Marc)>> Now that we have our pieces cut and cleaned up we can get them fit here. We can get suited up, weld them up. Let's see how this fits. Oh yeah, looks good. Using our Lincoln Electric tig 200 square wave welder we can make a few tacks... ♪ ♪ ...hammer the seams flat, and weld it up solid. ♪ ♪ All right, well we got both of our collectors modified and got the ball joints attached to them. Now we just need to make the connection from there to the inlet of our "X", and we're gonna do that with a socket and a couple of bent pieces of pipe. Well I want to use this 45 piece, and I think I need to cut in this bend here because this angle's too steep. So I'm gonna go ahead and make a cut here. That way I can get it fit into my "X" and then decide where I need to make the cut in the bend. ♪ ♪ This piece fit in here. ♪ ♪ And sure enough it's pointing too far in. So I need to make a mark in this bend here where I need to cut it to point directly at that collector. ♪ ♪ [ saw cutting metal ] ♪ ♪

(Marc)>> All right, let's see how that fits. Looks pretty good. I'm gonna get that tacked in now. ♪ ♪ All right, well we've got our exhaust system all fabbed up and mocked up in place. Now I do have to go back and tack all these joints in here, make a couple of mounts, and then I can pull the whole system out, take it over to the table, weld up the joints. We'll make those tacks... ♪ ♪ ....install the hangers, and mark where the mufflers need to be cut off flush with the pinch welds. Hey Tommy, can you give me a hand please sir.

(Tommy)>> Sure as long as I don't get any Mustang on me.

(Marc)>> Yeah, well, ready?

(Tommy)>> Sure. Ah, I got some Mustang on me. I need you to get me a towel.

(Marc)>> Go down and back!

(Tommy)>> It's starting to burn. ♪ ♪

(Marc)>> Now we can weld up all those seams. ♪ ♪ [ saw cutting metal ]

(Marc)>> And then cut through those boom tubes with a big cutoff wheel. [ saw cutting metal ] ♪ ♪

(Marc)>> Moment of truth. ♪ ♪ [ drill spinning ]

(Marc)>> And with our hardware in and tight we can behold the beauty of the boom tubes. They're gonna be loud but who cars right? They really compliment the looks of our Mustang, and before you know it this thing's gonna be screaming. ♪ ♪ You see us do a lot of welding here in the shop and most of the time we use a mig welder because a mig's very forgiving. It's got a spool of wire inside the machine. You just point, pull the trigger, and it'll lay down a very nice weld, but there's times when we need a nicer weld or when we're welding different types of metal, and in those instances we use the tig welder. Well for that you have to have filler rod and we're gonna talk about the different types today. This is the ER-70-S-six, which is for mild steel. This is the most common type of filler rod found in an automotive shop, and it's great for sheet metal, chassis, and suspension components. The dash six at the end means that it has more oxidizers in it than say a dash three would, which helps provide a flatter and quicker bead. It is an alloy, meaning it has other metals in it in small quantities, like copper and chromium, which are what gives it its shiny copper color. ♪ ♪ The next filler we're gonna talk about is the 308-L. This is for welding stainless steel to stainless steel. The most common types of stainless in an automotive shop like ours are 304 and 409, like the stainless tubes in our exhaust system, and this filler is ideal for that. It's an alloy of mostly iron with about 10 percent nickel and about 20 percent chromium, as well as some small quantities of other non-ferrous additives. But if you're going to weld stainless steel to mild steel you're gonna need the 309. The 309-L is ideal for welding non-similar steel like stainless to mild steel. Our exhaust system is a great example of when you would use this filler as we had to weld mild steel mufflers to our stainless steel tubing. This filler is comprised of about 13 percent nickel and about 24 percent chromium, as well as some other additives. You can also use 309 for welding similar alloys like 304 stainless to 409 stainless. Now we use those three here in the shop quite a bit but there's two others that we have here that we use from time to time. One is gonna be aluminum. This is only good for welding aluminum to aluminum, but then this other one is called silicon bronze, and this thing does just about anything. You can weld steel, bronze, brass, or any combination of those to each other. Now what's cool about this too is once you lay down the bead it's gonna be nice, and shiny, and gold. So if you're doing an art project or you just want something custom fabricated you can use this. You just have to remember it's not gonna be as strong as a regular steel weld would be. Well those are five common types. There are other types of filler rod, and you can even get these in different diameters but we'll talk about that another time.

(Narrator)>> Coming up our '85 Buick Regal gets a nip and tuck to make room for some big grip.

(Tommy)>> Hey guys, welcome back. We've got our Buick on the lift and we're ready to get busy on it. Now the task at hand for today is gonna be making some room for some big ole rear wheels. Now these tires right here are a pretty good size and all but I'm wanting to run even wider than this, and it's not exactly just gonna fit up under there. Let me show what I mean. To make the room that we're gonna be needing what we're gonna do is take this wheel tub here and move it inward here on the body. Now sometimes whenever you're doing this type of modification you'll run into the frame rail, but luckily for us our chassis guy accommodated us. If you look here in this hole we've got a couple of inches of room to play with. So what we're gonna do is cut this out, move it in just a bit, and do some trimming, and then weld in a new one. Now to do all that, yeah, it's gonna take some fab work but it'll be worth it in the end. So let's go ahead and get that one out of the way. I'm gonna start off by making a mark where I need to cut. We're not trying to save this old thing. So we'll cut it into a few pieces. After that I'll drill some holes so that we can get to cutting. The body saw has to be one of my favorite tools. Yeah it's a bit noisy but it makes easy work when removing panels like this. Up here on the front I drilled several holes and now it's just a matter of connecting the dots. Bam, it's that easy! Now we need to make a few marks so that we can cut out floor. Now what I'm gonna do is move it all the way in so that it's basically parallel or flush with the side of the frame rail. ♪ ♪ Now here on the rear of the frame you've probably noticed that it's kind of got a 90 degree bend in it, and the reason they did that is because there's a body bushing under here and they're trying to attach to it. Now what we're gonna do on the front side of that is we want it to be flush with the side of the rail. So we'll mark it just like we did up there. I'm gonna just eyeball this line using the frame as a guide. Then I'll get to spend a little more quality time with that body saw. [ saw cutting metal ] ♪ ♪

(Tommy)>> To fill up that big ole hole that we just cut in our Buick what we're gonna be using is a set of these factory style replacement wheel tubs that we got from Summit Racing. Now I could have made something out of flat metal, did a whole bunch of hammering and shaping, but for the style build that we're doing it's just really not worth it. But what we are gonna do is take this wheel tub, cut this lip off, and then we'll follow that up with a band to connect this inner to the factory outer. I'll make a mark all the way around the new wheel tub and use the line as a guide. When cutting an odd shape panel like this thing making a smooth, straight cut can be kind of difficult, but with that as a reference it's much easier. ♪ ♪ Looks like that's gonna work just fine. Now I've still got to do some grinding so that we can weld this thing up. So I'll go ahead and do that. Y'all don't run off. We'll see you here shortly.

(Narrator)>> Stay with us as Tommy tightens up our tubs.

(Tommy)>> Hey guys, glad you made your way back. While you were gone I went ahead and ground and wire brushed all in here, making preparations for some welding. I also added this little tab through here and right down here on the floor. That way it'll make it a whole lot easier to attach that new piece, and what I used was just a simple piece of sheet metal that I put in the break and made a 90 degree bend. Now what we need to do is take that wheel tub, fit it in there, and see if we need to tweak it any before we weld it into place. ♪ ♪ With our wheel tub all clamped in place the next thing we need to do is fill this void here in between the two, and to do that I'm gonna use a couple of strips of metal. It's pretty simple. What we're gonna do is take this, slide it under our factory lip and on top of this new wheel tub. We'll slide it around until we get the fit exactly where we want it, attach it with some panel clamps, and then burn it into place. I know this piece looks too big right now but we'll trim it down later. ♪ ♪ We'll start by installing several of these panel clamps. They will hold everything together and allow us to shape our filler panel as we go.

I like to tap the panel slightly because the vibration helps to tighten up the clamp. [ drill spinning ]

(Tommy)>> We'll put a few more fasteners here on the underside of the fender well because the trunk hinge brace is in the way to do it from the top. [ drill spinning ] ♪ ♪

(Tommy)>> We can mark our seams... ♪ ♪ ...remove the panel clamps, and slide out our filler piece. ♪ ♪ Using a pair of tin snips I will trim off the excess of our filler panel, cutting it about a half inch from our orange guide line. Now all that left to do is grind off the black coating on our new wheel tub. That ought to do it.

With our panel back in and all trimmed up now it's time to throw some sparks. [ welder crackling ]

(Tommy)>> I'm not welding the seams completely from top to bottom. I'm gonna weld it in half inch increments trying to keep each weld about an inch apart. Now where this panel is located you really don't have to worry about giving it too much heat and warping. Just make sure it's burned in nice and solid. ♪ ♪ That turned out pretty good and we've got some big gains for a little bit of work. Now I didn't get to address this corner because I'm gonna have to come back and fill in where the spare tire used to go. If you have any questions about what you've seen on today's show go to Powernation TV dot com. We're all out of time for now. So until next time y'all keep it between the ditches.