Hot Pipes

’67-’69 Camaro Exhaust Systems

Jeff Smith Sep 1, 2001 0 Comment(s)

Step By Step

The original Camaro exhaust layout featured twin 2-1/4-inch pipes that feed into a single cross-flow muffler located behind the rear axle.

The DynoMax system uses production-based compression bends that can reduce the inside diameter of the tubing. For the resto crowd, this is what you would want. Compression-bent tubing can also be slightly less expensive and will work fine for engines under 350 hp.

Mandrel-bent tubing uses an internal mandrel that prevents crimps in the tube and maintains the pipe’s inside diameter.

Virtually all dual-muffler systems require full-offset inlet-to-outlet mufflers to fit under the floorpan. The upper muffler is a DynoMax Super Turbo, while the lower one is a DynoMax Ultra-Flo.

The H- or X-pipes are common options for dual-exhaust systems. The idea is to tie the two exhaust pipes together. While some applications might increase power, that doesn’t always occur. Crossover pipes do offer a reduction in overall sound level.

The X-pipe shown here is by MagnaFlow. A similar unit is available through Dr. Gas.

Flowmaster was one of the first companies to build a dedicated exhaust system for early Camaros. This is the classic dual-muffler layout that uses 40- or 50-series mufflers and tailpipes.

The other Flowmaster system duplicates the factory single-muffler design. Flowmaster uses twin 40-series mufflers in this configuration, which offers a slight ground-clearance advantage but is kind of loud. Note that this system utilizes an H-pipe.

Torque Technologies offers 2-1/2-, 3-, and now 3-1/2-inch systems for the early Camaro. This is the 2-1/2-inch system using a pair of DynoMax Super Turbo mufflers. This design is limited to mufflers of no more than 17-inch case lengths, so we used the shorter 14-inch–case-length Super Turbos.

This Camaro used a set of Hedman intermediate-length headers, which required a short length of additional tubing with a slight 45-degree bend. Torque Technologies can supply these pieces, but we obtained this tubing from a local muffler shop.

This is the rear view of the Stainless Works chambered exhaust. Note how the pipes cross over behind the rear axle and then exit on the opposite side from the engine. Stainless offers almost two dozen different exhaust systems just for the early Camaro in both small- and big-block combinations.

These three circles illustrate the difference in internal square-inch area between 2.25-, 2.50-, and 3-inch exhaust pipes. We’ve calculated the area based on a wall thickness of 0.065. The 2.25-inch pipe has a flow area of 3.80 square inches, a 2.5-inch system increases the area 25 percent to 4.7 square inches, and a 3-inch pipe pumps the area up to 6.8 square inches.

Try this: Take a deep breath and then exhale through a small straw. Now try that while running around the block at full gallop. That’s what your engine is trying to do when you ask it to make power while exhaling through a restrictive exhaust system. While it may seem implausible, even a motor as mundane as a 283 two-barrel with a single exhaust will benefit from even a stock 2-¼-inch dual-exhaust system with a pair of performance mufflers.

First-generation ’67-’69 Camaros easily qualify as the most popular performance platform Chevy ever built. So it’s no surprise that several companies now build specific high-perf exhaust systems for this popular platform. We’ll take a look at a variety of these systems, give you the specifics on what’s available, and help you decide which setup would be right for your application.

Dynomax

Chevy’s original Camaro performance exhaust utilized a pair of 2-¼-inch pipes that led to a single cross-flow muffler mounted directly behind the rear axlehousing. This compact system allowed for maximum ground clearance but suffered from excessive backpressure. Some early performance applications also used small resonators located just ahead of the rear axle.

Walker DynoMax offers a direct replacement dual-exhaust system for the ’67-’69 Camaro that duplicates the stock system right down to the hangers and mount locations. The tailpipes exit between the bottom of the quarter-panels and the leaf springs. This is one of the least expensive systems available. The head pipes are intended to be used with stock exhaust manifolds. These stock replacement pipes can be ordered through most of the Camaro restoration companies like Classic Industries, Paddock, D&R, Rick’s First Generation, and Year One.

Flowmaster

Flowmaster offers two excellent mandrel-bent systems for the early Camaro, both in 2-½-inch pipe diameters. The first system duplicates the factory design using a cross-flow muffler. The advantage of this system is that the pipes tuck up very tightly to the floorpan, offering improved ground clearance for those who prefer that pan-dragging stance.

The disadvantage of this system is that the cross-flow muffler is actually two 40-series mufflers end-to-end that enter and exit from the same end. This makes for a very aggressive exhaust note that may be louder than you prefer. Don’t let the stock appearance of this system fool you. The exhaust note is just as loud as any other 40-series Flowmaster, which is plenty loud.

The second option configures a complete mandrel-bent system with a pair of small mufflers placed just ahead of the rear axle feeding into a pair of tailpipes. This system allows the choice of a couple of different Flowmaster mufflers to create the sound you desire. The Camaro’s lack of floorpan space limits the muffler case length to no more than 17 inches. The Delta-Flow mufflers may be the best choice here. The beauty of this system is that even with the limited space, there’s enough room for a complete 3-inch system. While that sounds bitchin’, keep in mind that larger-diameter tubes make the exhaust louder.

Torque Technologies

This company has built an excellent reputation for constructing quality exhaust systems for many popular GM body styles. Torque Tech has both ends of the Camaro performance spectrum covered with the popular 2-½-inch and 3-inch systems. It also offers the sewer-pipe–sized 3-½-inch kit that includes collector reducers, head pipes, and tailpipes along with a 3-inch balance tube and all mounting hardware.

We installed Torque Tech’s more mundane 2-½-inch system on a ’67 RS Camaro and found that it fit extremely well with plenty of clearance. Torque Tech can supply either Flowmaster or DynoMax mufflers with all of its exhaust kits. This particular system uses a pair of 14-inch DynoMax Super Turbo mufflers. This Torque Tech system is designed to mate to a pair of typical street headers, but in our case, we opted for a pair of Hedman intermediate headers. Torque Tech offers additional pipe length that can be used to make up the difference, but we elected to construct these intermediate pipes out of 2-½-inch pipe that we picked up at the local muffler shop.

Stainless Works

This company is only six years old but makes up for its youth with a large variety of exhaust kits for the early Camaro. Back in the late ’60s, chambered exhaust systems enjoyed some popularity, because they offered the least backpressure of any system available. But with reduced backpressure came an increased exhaust note. The Stainless Works system is quieter than the factory systems, but they are still loud.

While the chambered exhaust is interesting, Stainless Works offers factory-fit systems for original big- and small-block exhaust systems with the iron manifolds, as well as universal-fit systems for both small- and big-block Camaros with headers. All of these systems are offered in either stainless or aluminized tubing in 2-½-inch diameter tubing. Of course, all the kits are mandrel-bent systems. Not only that, but the company also offers the stock, single cross-flow muffler configuration in stainless, too. Other options include H-pipes, polished stainless tips, and a bunch of other goodies too numerous to mention here. In fact, there are 11 different part numbers for the factory-style exhaust systems depending upon tailpipe exit position and other details. The best plan is to check out the Stainless Works Web site, where you can find the entire catalog.

As you can see, there are plenty of options for plumbing your early Camaro with a professional-looking dual-exhaust system. Whether you drive a mild-mannered 327 or a fire-breathing, blown, Rat-motored Camaro, there is a system that will fit your needs.

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