Why Install High Performance Exhaust Systems?

Series Summary

The sound of your custom hot rod is key to the admiration of bystanders as you cruise down the street. If your huge engine sounds like a Geo Metro, you won't get much street cred regardless of your brand new custom headers and immaculate flame job. In addition to determining the roar of your hot rod, the exhaust system also has a great deal to do with the power. The right systems have large-diameter pipes and mandrel-bent turns to reduce the back pressure in your system as much as possible. Reductions in back pressure amount to increases in performance.

In this series of custom car performance videos, our hot rod expert and body shop owner Doug Jenkins demonstrates the installation of a custom exhaust and muffler system in a 1975 Chevrolet Caprice with a 572-cubic-inch 620-horsepower engine. To get this street monster up to maximum power, Doug and his crew install 2.5” and 3” pipe with mandrel turns. Watch as he demonstrates each step in this upgrade, from removing the old muffler to expanding and bending the new pipes to welding on the new muffler. Learn professional tricks for connecting the muffler to the exhaust pipes and fitting the entire system to the chassis of your custom car.

Video Transcript

"Hi I'm Doug. I work with twenty great guys in St. Louis at Doug Jenkins Custom Hot Rods, and we're going to do some work for you today on Expert Village. Now, Dave is going to show you how to put killer performance exhaust on a big car with a really big motor. This has a General Motors engine, it's 572 cubic inches, 620 horsepower at the flywheel on pump gas. The engine is in a 1975 Caprice, and it's a real specialty type car. What do they call these now? It's a donk. A big, square American car with 24 inch wheels, tons of chrome, tons of power. You can see the red metal flake paint job. The interior is a Louis Vuitton fabric, with leather to match, new convertible top. And the guy just wants scorching power. So first thing we're going to do is put in the three inch exhaust pipes, going back to real big high performance mufflers. And we're going to go with two and a half inch exhaust from the mufflers back, because it's real hard to get that three inch up and over the rear axle. This guy wants the exhaust dumping at the rear of the car. And as long as we have good big pipe going to the muffler, you'll lose a little bit of power through those two and a half inch pipes, but it's going to make for the best overall job. The best cost effectiveness and the best look."