Last month, as you'll recall, we gave an old workhorse Chevy fullsize truck new life with a Goodwrench replacement engine equipped with Edelbrock's Multi-Point Fuel Injection. The resulting performance improvements were pleasing, but knowing we could get more out of the energetic small-block with a little effort, we wasted no time in getting back to work.
Knowing that we were allowing more air into the engine, we figured, Why not make it possible for the spent gasses to exit just as efficiently? Edelbrock answered that question for us in the form of their TES (Tubular Exhaust System) Headers and Cat-Back System, which includes an RPM Series muffler. To make the package totally complete, we also selected a high-flow catalytic converter from CGS Motorsports.
The Header System improves the engine's ability to breathe, provides more efficient fuel economy, and most importantly, remains 50-state emissions-legal by retaining the use of all factory smog equipment (and the system will not void new vehicle warrantees). Extensive testing on behalf of Edelbrock has granted these particular headers an Executive Order Number, making them street legal on pollution-controlled vehicles. Manufactured from 409 stainless steel, the exhaust comes with a "shipping-protective" black paint that burns off at normal engine temps, so alternative coating should be arranged prior to installation, if desired.
The Cat-Back System, including the CGS cat, will work perfectly with the headers, providing less-restrictive flow than stock systems. Each mandrel-bent 16-gauge system is designed as a stock replacement, which means installation is a breeze. The RPM Series muffler (constructed from 409 stainless) features the patented Tru-Flow core design for improved sound and increased performance versus a typical baffle-type muffler, and is also street legal in all 50 states. And while the system is built to work with a stock catalytic converter, we chose to use CGS's higher-flow, weld-on cat for obvious reasons.
This phase of the upgrade started out at Barry White's Street Rod Repair, where Chad Vogele aptly handled the task of installing the Header System. One evening after work was all it took to get the headers bolted up, and the only hang-up we encountered was a pierced power steering pump (our fault). For the interim, the new connector pipe was tack-welded to the old catalytic converter until the remainder of the exhaust could be installed.
The next morning, we made an appointment at Apollo Muffler in Santa Ana, California, to finish up the job. With Apollo's talented staff, the wrap-up of our exhaust system took just under an hour to complete, including extra welding that isn't required (such as some of the slip joints). Once finished at the muffler shop, we got our first earful of the Edelbrock performance exhaust system, and were quite pleased. The real test, though, was yet to come.
The following week, a follow-up to our first dyno run was scheduled with Paul Trujillo at K&N Engineering in Riverside, California. We wanted to see exactly what horsepower and torque benefits the complete Edelbrock system provided compared to the earlier test results. When all was said and done, the truck produced a more than acceptable 173 hp at 4,400 rpm, and 238 ft-lb of torque at 3,100 rpm-quite a substantial improvement from what the small-block put out with just the Multi-Point Injection.
So, maybe this is not the high-horse Mouse motor that most readers dream about, but it sure gets this parts hauler around town (and across the highways) in fine fashion. Good throttle response, efficient fuel economy, and a healthy exhaust note to boot-the old workhorse is back and ready for action!