We've said it before and you've read it before: You can't just bolt on a random combination of parts and expect to see serious performance gains. The key to getting a solid increase in torque and horsepower is finding the right combination of parts. Sure, you could buy yourself an assortment of accessories, rent some chassis-dyno time and have fun seeing which parts work best together. But that's a little cost-prohibitive and labor-intensive for most of us.
Fortunately, there are plenty of people who make their living doing this kind of testing. And they've very graciously put together performance-enhancing packages based on the results of their research.
Here we've got the scoop on 18 different parts combinations that will improve the performance of a wide variety of 4x4 vehicles. To be included in this story, the parts had to be sold as a package. This makes your life easy: All you have to do is call up these companies and tell 'em which kit you want.
The convenience factor is a big reason why we love these kits. But the dollar-to-value ratio is the biggest reason. By purchasing parts that were designed to work together in harmony, you'll be spending your money wisely, and you'll be getting the grunt you and your rig deserve.
Package name: SysteMAX II
For which vehicles? Trucks with '67-'86 Chevy small-block engines
Horsepower gain: As much as 150-200 (depending on original engine), with new and improved total power output of as much as 425 hp (on a fresh 355 short-block with 9.8:1 compression, zero deck clearance and 1 5/8-inch headers using a 750-cfm Holley Double Pumper carb)
Torque gain: As much as 150-200 lb-ft, with total torque of more than 400 lb-ft
What's in the box?
* A Lunati camshaft (235/240 duration at 0.050-inch lift, 0.490/0.490 lift, 112-degree lobe separation, 107 centerline)
* High-bleed flat tappet hydraulic lifters
* An intake manifold
* A timing set
* Hardened pushrods
* ARP head bolts
* Holley aluminum cylinder heads with provisions to bolt on all engine accessories; they feature heat crossover passages, 68cc combustion chambers and 2.02/1.60-inch exhaust/intake valves
Why would I want it? You'd be getting a seriously torque-oriented setup that's still mild enough to run happily on pump gas. The Lunati cam was designed to provide greater air-charge density, maximize mixture combustion and give constant port velocity. And the double-roller timing chain and gears provide smooth, precise timing for more power production.
How much does it cost? $1,800
Contact: Holley Tech Service, Dept. FW, P.O. Box 10360, Bowling Green, KY 42101, 270/781-9741, for nearest dealer: 800/HOLLEY-1, www.holley.com
Package name: Rat Pack Performance System
For which vehicles? '00-'04 GM trucks and SUVs with the 5.3L Vortec engine (packages are also available for '94-'04 Dodge Rams with gas engines and '97-'04 Ford F-150s and F-250s with gas engines)
Horsepower gain: 40 hp at the rear wheels
Torque gain: 60 lb-ft at the rear wheels
What's in the box?
* Gibson after-cat exhaust system
* Airaid intake
* Airaid throttle-body spacer
* Hypertech computerreprogrammer
Why would I want it? Desert Rat's team has researched a wide combination of parts from various manufacturers and put together this package focusing on performance, price and quality; the team created what it calls the "power-to-price ratio." Plus, the focus is on torque even more than horsepower. And we're talking low-end torque at that, thanks especially to the throttle-body spacer, which increases torque from off-idle to 3,500 rpm. The intake also gives you faster air delivery and more flow, while the exhaust reduces backpressure. The computer tuner brings it all together, and allows you to change shift points and make additional tuning modifications.
How much does it cost? $875
Contact: Desert Rat Truck Centers, Dept. FW, 3705 S. Palo Verde, Tucson, AZ 85713, 866/241-5337, www.desertrat.com
Package name: Truck Super Tune-Up Kits
For which vehicles? Eighteen applications covering most Chevrolet, Dodge, Ford, GMC and Jeep late-model six- and eight-cylinder pickups, vans and SUVs from the mid-'80s to current
Horsepower gain: 5 to 10 percent
Torque gain: 5 to 10 percent
What's in the box?
* A matched ACCEL custom-fit wire set
* An ACCEL distributor cap and rotor
* ACCEL U-Groove spark plugs (some kits are available with ACCEL Shorty Header Spark Plugs if you need added clearance because of headers)
Why would I want it? This setup is able to tolerate lots of heat and make more power, plus it dramatically improves driveability. The quality of the parts is much higher than a typical tune-up kit too. The race-proven ACCEL U-Groove copper-core spark plugs maximize burn efficiency for improved performance and reduced emissions. The 8mm custom-fit Extreme 9000 wire set has heat-reflective-coated spark-plug boots rated to 1,200 degrees F., and the double silicone wire has a low-resistance Ferro-Spiral core. The distributor cap and rotors are precision molded of impact-resistant high-dielectric-strength compounds, with brass or copper inserts and stainless steel contact springs.
How much does it cost? Starting at $79.95
Contact: ACCEL, Mr. Gasket Performance Group, Dept. FW, 10601 Memphis Ave., No. 12, Cleveland, OH 44144, 216/688-8300, www.mrgasket.com