Flowmaster Dual Exhaust On A 1973 Chevy C10 - DIY Dual Exhaust

1. The Hedman Hedders we installed onto our LS327/327 crate engine send the exhaust gases out of 3-inch-diameter ball-and-socket-type collectors. We'll start building our exhaust by bolting a pair of female sockets onto the header collectors. These particular sockets were left over from a previous install done at the shop.

2. Josh, who owns the shop, positioned the mufflers inside of the framerails, taking into consideration where the exhaust tubing would be routed and any accessories that might be in the way. The Flowmasters have offset inlets, which means you can flip them over to position the tubing next to or away from the driveline.

3a. An adjustable ruler with a center pivot was used to find tubing that had the correct bend to connect from the mufflers to the collectors. The tubing wasn't a perfect fit so Josh marked the portion that needed to be cut off.

4a. The tubing was shortened in a chop saw. You can use a reciprocating saw or bandsaw, but the chopsaw ensures a nice, straight cut. Each end of the tube was sanded smooth and then the burrs were filed off of the inside lip.

5. After cutting the downpipes, they fit the collectors perfectly and pointed right at the muffler inlet.

6. This view shows why we installed BRP's tranny crossmember: Without the extra clearance, the exhaust pipes would hang even farther below the framerails.

7. Before mounting the mufflers or welding the tubing together, the collectors are bolted together to make sure nothing moves out of alignment.

8a. The slip-fit pipes can be clamped together, but we decided to weld the tubes together at the same time we welded the muffler hangers in place. The advantage to using the tubing clamps is that you can take the system apart easily later on if you need to.