Propickup Digital Magazine
Issue link: https://read.dmtmag.com/i/93727
INSTALL S ix years ago I was looking for ways to boost power and fuel economy in my 2002 Chevy TrailBlazer's 4.2L inline-six. A gearhead always curious about new aftermarket upgrades and technology, I turned my attention to Airaid. The company touted their cold-air air intake systems and "throttle-body" spacers as keys to improving both horsepower and fuel economy. Airaid claims the design of the machined spacer, which uses a "helix-bore" to spin and maintain the velocity of the air/fuel mixture, helps provide better combustion. Better combustion means a more effi cient fuel burn. Ever the skeptic of such claims, I installed both and worked with a performance dyno shop in New Orleans to document the eff ect each part had on horsepower. The results were surprising. The Poweraid spacer, by itself, added 5hp to the 4.2L in the 1,500-2,100rpm range and showed similar hp boost again above 5,200rpm. Subsequent road tests showed a 1mpg (6%) gain in fuel economy at 65mph. Combined with the Airaid cold-air intake, the 4.2L gained 20hp in the low- mid rpm and 1.5mpg on the highway. I want to see if Project Bedrock, my 2011 GMC Sierra 1500 with the 5.3L V8, shows similar improvements with some intake upgrades. To that end I've installed an Airaid Pow- eraid throttle-body spacer and high-fl ow Airaid lifetime air fi lter; the installation of the spacer is very simple, takes about 30 minutes, and requires nothing more than a screw- driver and 3/8-inch metric socket set. We don't have access to a dyno here at the magazine. But I do keep an accurate mileage log and have a good feel for how my truck performs so I'll be able to note any signifi cant improvements over the next few months. And should I not be happy with the results, Airaid says the Poweraid T-B spacer exhibits the biggest power improvements in the lower rpm (1,500-1,800rpm). This should mean a gain in mpg at highway cruise speeds. Use a 5mm torx socket to remove the top studs. They will be replaced by Airaid's longer bolts. Airaid has a Lifetime "No Hassle" Warranty that gives your money back if you aren't satis- fi ed with the results. To check up on the results, go to the Proj- ect Bedrock logbook on our website under the "Project Trucks" tab. Remove plastic engine covers and the air intake tube from the throttle-body. Use a 10mm socket to remove the two top nuts and two bottom bolts that hold the T-B to the in- take manifold. Then pull the T-B away from the manifold. Position the Poweraid spacer and gasket on the T-B with the "Flow" (arrow) facing toward the intake and "T.B. SIDE" facing the throttle-body. A LL SPACED Airaid Poweraid throttle-body spacer install brings incremental performance increase to GM 5.3Ls 42 PROPICKUP June 2012 By Bruce W. Smith