By Bryan Irons
Ah yes, the lowly exhaust system, a vehicular equivalent to the human colon. We will excuse ourselves from any gaseous dad jokes and simply state that it is the unsung champion of a properly working engine… and body. A properly working system barely gets noticed, but a poorly designed, maintained, installed or worn out exhaust can cause a melee of trouble.
It’s not that we dislike the work, or the design, or installation itself, but the vast majority of our experience with exhaust systems involves dealing with them after they are installed. Little time gets put into the idea of future maintenance such as having to remove engine components, transmission, transfercase or any other system that is installed in the underside of a vehicle. And the last component installed, is normally the first one that needs to come out.
The current system on our Tim Toyota project rig was likely installed in the early 90’s and can be described as the epitome of a ‘crapastic’ exhaust. Between the kinked bends, no crossover pipe, and rotting hangers, it was time for a change and we were determined to do it right this time.
Scrolling through Summit Racings online catalog we did our normal gig of selecting all the “wants” for this project and then throttling back our desires to what we can live with and afford to do to get the job done. What we ended up with was a set of Pipes Downpipes (PN DGU14S) that connect to our factory style exhaust manifolds, Summit Racing aluminized steel mandrel bent 2.5” exhaust pipe kit (PN SUM-670146), and a Dynomax 2 in, 2 out X-pipe muffler (PN WLK-17553). We also needed hangers and exhaust clamps, so we ordered Summit’s band clamp for a lap joint (PN SUM-692250-1), two V-band style clamps (PN SUM-695925), hangers for the exhaust ends (PN SUM-610310-1) and a set of AP Exhaust clamps for further up in the system (PN APH-8301). After shipping we were just shy of $800, which may seem like a lot of cash, but we also selected some top shelf components that won’t let us down and are built to last under an off-road vehicle.
There are plenty of installation methods including using crush clamps or band clamps, but we prefer to weld systems where removable pieces are not required. We also prefer to be able to install and remove the entire system in pieces without having to take out any other components. The goal is to be able to take out the entire system while on the trail using simple hand tools.
MIG, TIG, braze or even stick welding can be done, but we prefer MIG welding these components as we do have some stainless to mile steel transitions. Installing an exhaust system is a great project to practice your welding skills. We took advantage of this opportunity to practice our non-existent TIG welding skills on with our new Miller Syncrowave 210. With some careful cleaning and grinding of the weld area, and numerous trips to sharpen our Tungsten electrodes after messing up, we were able to fuse the pipes together without feeling too embarrassed with the finished product. That being said, we still coated all the joints in a Bright Galvanizing paint to keep the inevitable rust at bay.
Exhaust work can be a tedious job of fitting and grinding to get components to fit exactly how you want. Starting with quality parts and thinking about the future of your off-road rig can make the difference between never giving the components a second thought, and wanting to burn the truck down. We spent the better part of 10 hours in the shop puttering on this installation, but to be honest, most of that was spent fiddling around with our TIG settings and finding a radio station that didn’t make us wish for a hot spark to drop into an ear canal.
Ratchet straps, string and jack stands can be your best friend for a job like this… and they won’t raid your shop fridge while your welding lid is down. Here’s how it came together.
Summit Racing – https://www.summitracing.com
Dynomax Exhaust - http://www.dynomax.com
Miller Welders - https://www.millerwelds.com
1 of 14
Bryan Irons
2 of 14
Bryan Irons
1.
As we rolled Tim into the shop, we smelled fuel. Since we were about to start generating sparks and flames, this little leak HAD to be fixed. Make sure to keep any flammable material out of the way of your work.
3 of 14
Bryan Irons
2.
Don’t overlook the therapeutic value of removing a junky pile of scrap using brute force. It would appear that enough muffler cement to seal a sieve was used in the past. This stuff is great for new joints and flanges, not “repairs”.
4 of 14
Bryan Irons
3.
The steel in exhaust systems suffers through a lot of heat cycling during its lifetime and we had some bad threads in our passenger side manifold. A thread repair kit was used to save the day and the stainless insert should last the lifetime of the old Chevy V8 under Tim’s bonnet.
5 of 14
Bryan Irons
4.
Jack stands are your friend, use them and any other method of blocking to get the piping in place and ready to tack together.
6 of 14
Bryan Irons
5.
For permanently holding the system in place, we prefer this style of bracket, as they have a little movement. Instead of U-bolt clamps, we prefer to weld the brackets directly to the exhaust system. This takes more time, but you will not have to worry about crushing the tubing, or bolt heads dangling down and contacting the trail.
7 of 14
Bryan Irons
6.
For sections of pipe that may require removal in the future, we much prefer the V-band clamps on the right. The positive seal and precise fitment make them a pleasure to work with. In places where access may be a bit more limited, or the piping may have to extend or collapse a bit, we prefer the lap joint style clamps on the left. The lap style is used where exhaust piping fits into each other, or butt style clamps can be used as well.
8 of 14
Bryan Irons
7.
Once you have marked or tack welded your pieces into position, and have them on your welding table, keeping proper tubing alignment is key to a free-flowing exhaust. We have seen miter cut systems in the past with welding wire used to fill gaping holes. Please don’t. Proper fitment is not difficult, but it does take time.
9 of 14
Bryan Irons
8.
A wipe down with acetone to get rid of any lube that was used in the tube bending dies will give you a much better weld. Do NOT use chlorinated brake cleaner!!! The fumes that can be emitted from the welding process can be lethal.
10 of 14
Bryan Irons
9.
With aluminized exhaust pipe, we like to grind the aluminum coating off before welding. It’s not completely necessary with MIG welding, but the coating is just another contaminant to get into your weld pool.
11 of 14
Bryan Irons
10.
We don’t care what method you use to fuse your system together, just make sure it leaves you with a strong joint that can with stand heat and abuse. Some of our system we MIG welded, others we TIG welded. Our TIG welds laid out flatter, but the MIG was MUCH faster.
12 of 14
Bryan Irons
11.
All of our V-Band welds we TIG welded to try and keep any weld spatter off of the mating surfaces. You can also wrap the area to NOT be welded in aluminum foil. We went in with a die grinder and smoothed out the inside of the tubing where we could reach.
13 of 14
Bryan Irons
12.
After a coat of Bright Galvanizing paint and grinding the inside, the pipe was ready to reinstall.
14 of 14
Bryan Irons
13.
We chose the single muffler to act as a crossover pipe, and having one leaves only a single muffler to worry about getting hit underneath. The welded design of the Dynomax is EXTREMELY strong and the sound is smooth without any drone inside the cab. All that was left was to weld the remainder of the system and hit the trail!