- A full exhaust system starts at the manifolds, which are bolted to the engine. These manifolds feed a "Y" pipe that joins the opposite banks' exhaust streams into a common outlet, and it is fed from there through a catalytic converter. The single exhaust pipe then carries spent gases through a muffler, over the rear axle and out the back.
- A full exhaust system replaces the cast iron exhaust manifold with tubular headers, and may or may not connect to a Y-pipe, depending on whether or not the buyer specifies single or dual exhaust. A high-flow catalytic converter replaces the restrictive stock unit. Dynomax supplies smooth mandrel-bent tubing for all its kits, which routes the exhaust gases through a new muffler of the buyer's choosing, to exit either ahead of or behind the rear axle.
- When most people refer to a bolt-on "exhaust system," what they're really talking about is a "Cat-Back," which replaces the entire exhaust system from the catalytic converter to the tailpipes, allowing the vehicle to retain emissions compliance. For these applications, DynoMax offers a single bolt-on exhaust, utilizing mandrel-bent 2.5-foot tubing, a Super Turbo Muffler and a stainless steel slash-cut tip.
- The efficacy of any exhaust system replacement depends on where the greatest impediment to flow is located. In the 4.3L Blazer, this is generally in the catalytic converter or Y-Pipe, so replacing anything aft of that probably won't yield any massive jump in horsepower. DynoMax claims up to 20 horsepower, but most comparable cat-back systems are known to produce more in the range of 2 to 5 horsepower.
- In and of itself, no cat-back system is going to turn your truck into a dragster. When modifying a vehicle for increased efficiency, one must take a systematic approach to address the greatest impediments to both intake and exhaust flow in order to take advantage of any individual modification. Consider replacing the stock catalytic converter and Y-pipe to uncork the exhaust, and open up the intake side of the equation with an aftermarket cold-air intake system like those sold by K&N.
