When it comes to 'bagged trucks, most of the tech revolves around how to get crossmembers and suspension components above the frame line - who wants to drag that stuff? So, we're assuming you all know how to move the tranny crossmember up, but what do you do with the exhaust besides cutting off the tailpipe? Thanks to MagnaFlow's Hot Rod Kit, you can design your own pipes to your specific needs without having to go to an exhaust shop. Hot Rod Kits feature mandrel-bent universal tubing in various straight and curved sections in 2-1/4-, 2-1/2-, or 3-inch diameters. You might be thinking about whether or not this will this affect emissions legality. As long as you don't move the factory cat placement, you'll be fine, which is why most aftermarket systems are after-cat setups. If you can weld in a C-notch or shave your door handles, then you can do this.
Your selection in tubing size should be based mostly off your engine size. For instance, assuming the engine is not force-inducted and the engine is operating at normal speed (no higher that about 5,800 rpm), 2- through 2-1/4-inch-diameter exhaust tubing will support 200 ci. At 2-1/4- to 2-1/2-inch exhaust tubing, a 250ci engine can be supported. At 2-1/2- to 3-inch tubing, a 350ci engine can be supported. At 3- to 4-inch, a 400ci engine can be supported. This information is based on flow, so if you're running a true dual (not two pipes in one muffler, or two pipes in one cat) system, you can double the number of cubic inches the exhaust system will support.
You will find some slight overlap in the supplied information, but this all is dependent on how many bends and how long the exhaust tubing is. Your best bet is to look at the job first, take some measurements, and estimate how many bends will be in place, and how much tubing will be used. Call the techs at MagnaFlow and relay the information to them. They will be more than willing to help you determine what size would be best for your project. Here's a quick show and tell, thanks to John Meyer of Clean Cut Creations, on a Hot Rod Kit install.
1. Here is the kit from MagnaFlow....
1. Here is the kit from MagnaFlow. It comes with all the bends and tubing you will need. The company also sent out one of its killer mufflers, and a nice, fat tip adds some growl and some style.
2. As you can see, the stock...
2. As you can see, the stock muffler hangs well below the scrubline and even has a few draggin' scars to prove it. Now you see why we need this kit.
3. The first order of business...
3. The first order of business is to drop out the stock exhaust behind the catalytic converter. You may need a reciprocating saw to remove the rear section of pipe. Since this system was already cut for suspension clearance, it came right out.
4. A custom after-cat system...
4. A custom after-cat system means you have the liberty to start wherever you like. Just make sure it's after the cat, and O2 sensor, if there is one. Running the system straight back behind the cat allowed John to remove some of the bends that were put in the stock exhaust system. With the flanges temporarily bolted together, he mocked up the best place to start.
5. After marking the exhaust,...
5. After marking the exhaust, the section of pipe was removed.
6. The mighty saw makes quick...
6. The mighty saw makes quick work of the exhaust tubing. Whoever coined the phrase "the tool doesn't make the mechanic" never tried to saw through stainless with a hack saw.
7. Deburring the freshly cut...
7. Deburring the freshly cut tubing is critical because the sharp edge may do more than cut your flesh deep and wide. The burs may also come off with heat and contaminate the muffler; not to mention, it's hard to weld one pipe to another when the edges are uneven.
8. John put the pipe back...
8. John put the pipe back in the truck and mocked up the new flange. John says, "Along with marking the tub for length, make sure to mark the side of the tub to ensure the rotation of the flanges is not out of line with the body. This will make accessing the bolts easy and give you a point of reference when you go to weld."
9. With all the marks in place,...
9. With all the marks in place, the flange was welded on and the pipe put back in the truck.
10. The other end of the flange...
10. The other end of the flange was welded to a straight length of tubing, then the two units were bolted together. Then, John moved to the back of the truck and placed the muffler.
11. The leading edge of the...
11. The leading edge of the muffler was trimmed down to provide clearance for flange placement.
12. Once the proper muffler...
12. Once the proper muffler orientation was determined, the muffler tip and flange were welded to each end.
13. With the muffler in place,...
13. With the muffler in place, John marked the exhaust tube for length and cut it to size.
14. Then he took it back out...
14. Then he took it back out and welded the flange end to the freshly cut pipe, and bolted the muffler to it.
15. With a jackstand holding...
15. With a jackstand holding the new exhaust systems in place, we needed to locate a good area to weld an exhaust hanger. John cut the factory piece from the frame and moved it to where he needed it.
16a. MagnaFlow's hanger wraps...
16a. MagnaFlow's hanger wraps around the muffler and provides an area to mount the hanger. John decided to drill holes and bolt it to the muffler while the other end slides into the factory rubber.
16b.
17a. By the front and rear...
17a. By the front and rear view, you can see the finished product is a nice piece. The new muffler is significantly smaller in size, providing clearance, and rerouting the exhaust simplified it and cleaned it up. With a kit installed like this, you can have fun draggin' your truck on the 'rails instead of the muffler.
17b.