Seven Bolts For Seven Horses
A Simple and Effective Bolt-On Exhaust Upgrade for an S-10

By: Scott Parkhurst

   The PHR Truck Tech section isn't just about V-8 stuff. While the little S-10 we're focusing on in this story wouldn't make a great tow vehicle, it's a fine daily driver/parts runner. The anemic little 2.2L four-popper won't break any world records, but the fuel economy, cheaper insurance rates, and lower initial investment price all contributed to deciding it'd make a fine commuter vehicle. The benefits offset the "negligible" fuel economy delivered by a big-inch V-8 designed for serious duty. It's got such niceties as ABS and a driver-side airbag, and after it gets a mild lowering job and a decent wheel/tire upgrade, it should prove to be a capable way of getting around town.

   If a few more ponies and better aural attitude are simply a couple hours and a few dollars away, why not see if we can add more pickup to the pickup? A basic catalyst-back exhaust system is a good call, and in researching this story, we found plenty of access to the components under the truck and a system from MagnaFlow that would bolt right up. We wanted to see how much rear-wheel horsepower (if any) a simple upgrade like this would add. We did find 7 hp, which may not seem like much to readers used to seeing much more. But, when you consider we started with less than 100 horses, that's almost a 10-percent gain with minimal effort and expense. We'll add a high-flow airbox/filter assembly later and hopefully pick up a couple more horses. These higher-flowing additions may add power we can feel in the pedal, but in freeing up the engines breathing capabilities, we're also making it easier for the little powerplant to pull us down the road. This means we should see increases in fuel economy, as well.

   The entire exhaust system upgrade forced us to remove and replace a total of seven bolts: three at the back of the catalytic converter, and four securing the clamps at either end of the muffler. The stock hangers were reutilized, and the system looks, works, and sounds much better. Easy? You bet-and there are plenty of upgrades just like this that allow you to tailor the look and sound of your system to meet your personal tastes. If you've got a factory system under your pickup now, it's worth the effort to investigate the many options out there for your particular ride. We did, and the simplicity was rewarded on several fronts. Check out the photos and see how easy it was to work with seven bolts and find seven horses!

The new box is actually a metal tray that acts as a heat shield (remember, the key to power is cold air) and is sealed to the hood by a piece of foam (which you shape around the tray and cut to fit). You must carefully remove the mass-air meter from your old airbox and install it on the FIPK and don't forget to read the directions closely to see how to sandwich it between the gasket and the heat shield.


The heat shield, with the mass-air meter attached, simply bolts into the airbox's old home and there is lots of room to add that giant, re-usable filter.

Dropping the factory system was no sweat. There are three bolts tying it to the catalytic converter, and the rest is secured with the factory rubber hangers. We hit the rubber hangers with penetrating oil before trying to remove anything-it truly helped!

Seen side-by-side, we can see where the MagnaFlow system (PN 15706) adds a bit of diameter (2.25-inch vs. 2-inch) and smoothes out the bends. The factory muffler is both quiet and restrictive, where the MagnaFlow part is a high-flow, straight-through design, and the pipes have gentler bends. It all adds up. All MagnaFlow catalyst-back exhaust systems are stainless steel, too. We'll never worry about corrosion. Careful design and top-quality manufacturing methods and materials make for exhaust systems that should out-last the vehicles they're installed under, and that kind of insurance help justify the investment.

Back on the rollers, we found a nice power gain all the way throughout the rpm range. Check the chart for the numbers, but the tiny truck feels a bit more peppy and sounds like it want to be a full-size some day. That might take a V-8 to accomplish, but for now, we're very satisfied with the direction our little shop truck is headed. Once it gets the proper stance, wheels, and tires, we'll call it finished.