Back when we rebuilt and installed the 401-c.i.d V-8 in our '65 Buick Riviera, "Project Low Rod," we knew that we'd eventually be installing a new exhaust system to help the "nailhead" engine pass gas better. Well, that time came, so we took a trip down to the R&D facility of MagnaFlow Performance Exhaust (in beautiful Rancho Santa Margarita, California) to see what the experts in low restriction high-performance mufflers and exhaust suggested.
We contacted director of product development Mike Jones and engineer Jim Gose, who put the Rivi up on the lift and checked out the old side-exiting exhaust system. It was rusted, bent and generally in need of replacement. After some research, a game plan was developed that included keeping the factory exhaust manifolds. Apparently they were designed better than what little is available in the aftermarket for this rare engine, so no headers would be added.
Instead, all-new 21/4-inch stainless steel exhaust pipes would be custom mandrel-bent, connected to the stock flange, tucked up inside the frame and over the rearend (to clear the rear air bags) with two 6-inch and two 4-inch aluminized round body MagnaPack mufflers and chrome turn-down tips installed.
The MagnaPack mufflers have an all welded, 16-gauge aluminized stainless steel body, end caps and one-piece core to provide life long protection from the elements. The straight-through design has no chambers, no baffles, no louvers and no restrictions so they outflow OEM chamber-style mufflers by as much as 167-percent. This reduces engine heat and back pressure, and improves exhaust scavenging from the combustion chamber, thus restoring torque and horsepower to the engine.
MagnaFlow offers complete performance exhaust kits (including their own Mirror Finish SS High-Flow catalytic converters) for most popular late-model import and domestic cars, trucks and Euros. Universal kits are also available, as well as the popular Hot Rod kits that include mandrel-bent stainless steel 21/4- or 21/2-inch straight, 45-, 90- and 180-degree bend pipes and hangers.
Adding to the credibility and reputation that MagnaFlow has earned in the performance community, the company proudly announced at the 2001 SEMA Show held at the Las Vegas Convention Center, that Mario Andretti has signed a four-year exclusive product endorsement agreement with the company.
"We are very proud that we will have Mario Andretti on our team," stated Jerry Paolone, president of MagnaFlow Performance Exhaust. "Mario is one of the most recognized names in the world. He is certainly the most recognized name in Motorsports. I am very pleased that Mario Andretti believes in our company and finds our products worthy of his endorsement. This is a personal honor for me, my family and the fine people who work for MagnaFlow."
Check out the photos to see how slick our Rivi looks now (thanks to Jim) with its shining new low-restriction performance exhaust system. The system sounds even better than it looks. Plus, even though we didn't add headers, dyno figures revealed a slight increase in horsepower and torque. For an abundance of great tech material, applications, facts about the company, its products and more, check out MagnaFlow's Web site.
1. Our Project Low Rod rides the chassis dyno at MagnaFlow's R&D facility to establish baseline horsepower and torque figures before installing the new high-flow exhaust system.
2. The old exhaust system was rusted and ready to be replaced. Note how the driver's side muffler had been scraping the ground when the car was laid.
3& 4. The existing exhaust system tailpipes exited out the side in front of the rear tires; not the look that we wanted.
5. Director of product development Mike Jones looks on as product development engineer Jim Gose test fits a MagnaPack round muffler on the rear.
6 & 7. After considerable discussion and test fitting, Jim determined that two 6-inch MagnaPack and two 4-inch round mufflers would be installed. This would keep the dB down to legal limits and provide a low-restriction system. | 
8. MagnaFlow offers a variety of rolled edge and DTM polished stain-less steel tips to accentuate the rear of the vehicle. We chose the turn-down style. |
9. Although our Rivi didn't need them, MagnaFlow also offers their own Mirror Finish SS High-Flow catalytic converters. | 
10. Here we see the 2 1/4 inch stainless steel mandrel-bent exhaust system that Jim custom built for the Buick. |
11. It looks clean and tucks up tighter than the old system. | 
12. Because of their free-flow design, the stock exhaust manifolds were kept instead of replacing them with aftermarket headers. The new pipes were attached to new mounting flanges. |
13. One round muffler was installed just ahead of the rear tires but tucked up high enough to clear when the car is laid. | 
14. The exhaust was routed up over the rear axle between the shock and the tire; quite a feat. |
15. Another round muffler was tucked up high on each side of the gas tank. | 
16. The mufflers are the shiniest part of the undercarriage now. The look is very cool. |
17. Jim just tack-welded the turn-down tips on for now since we may be changing them later on. The system sounds as nice as it looks. | |