You may need an 8-rib serpentine drive conversion to handle the power and RPM of your small block Chevy. It's now easier than ever to achieve 500-plus HP. At that power level, you've probably spent a lot of time considering cylinder heads, fuel injection, and other components. These same factors also enhance RPM potential to 6000 RPM and beyond without much effort. Any hot rodder worth his gear shift would do anything for more power.

Managing all that performance potential is a different challenge, especially when selecting an accessory drive system. While it is possible to get by with a 6-rib serpentine belt, you may upgrade to an 8-rib setup. There are a few things to consider. Can your alternator operate reliably at peak RPM and also charge at idle? With a typical 3:1 pulley ratio, 6000 RPM at the crankshaft means 18,000 RPM at the alternator. What about power steering? Is your pump tuned to match your steering gear's pressure and flow needs? Does your system have enough belt wrap? Will your tensioner hold up to the increased loads? Let's explore these questions and more.

6 rib or 8-rib serpentine belt?

If you drive a cruiser, a typical 350-450 horsepower small block Chevy engine gets the job done. Let's face it, cruisers rarely exceed 4500-5500 rpm and experience only moderate steering inputs in normal driving. The biggest challenge for a cruiser is might be managing engine temperatures in traffic. For this scenario, a quality 6-rib serpentine drive should be more than adequate. A 6-rib serpentine belt provides at least one and a half times more contact area than an old V-belt. A well-engineered system will drive all accessories without belt slip. A spring loaded tensioner eliminates the need for regular belt adjustments.

For more aggressive applications, a true 8-rib design is highly recommended. So what is considered "more aggressive" when it comes to small block Chevy engines? Any combination of the following. 

• More than 500HP
• Engine regularly sees max rpm
• Max rpm for extended periods of time (such as track days, standing mile)
• Frequent transient throttle application (such as autocross - quick changes from acceleration to braking)
• Power adders like turbos and/or nitrous
• Anyone who just wants the ultimate system

Just a wider 8-rib belt or is there more to the design?

Any hot rod that meets one or more of the criteria above should consider upgrading to an 8-rib serpentine system. Primarily, an 8-rib belt offers 33% more surface contact than a 6-rib belt. That's beneficial, but be cautious of companies that only sell a wider belt and pulleys. To truly satisfy the requirements, Concept One adds an idler to increase belt wrap and upgrades the tensioner to a heavy-duty OEM model designed for high-torque diesel applications. The HD tensioner features a higher-rate spring to handle the increased loads and shocks from the main drive pulley. The wider belt, additional idler, and HD tensioner work together to ensure smooth operation of accessories across the RPM range and under different loads.

High performance charging system considerations

Concept One features a Powermaster CS130D type alternator with a standard 3:1 pulley ratio. Powermaster advises an 18,000 rpm limit for this setup. Calculating backward, the alternator needs a 6000 rpm engine redline. If your engine often surpasses 6000 rpm, Concept One can adjust your pulley ratios to slow the alternator's speed relative to other accessory drive parts. 

Slowing the alternator might reduce charging at idle. If so, Concept One can upgrade your system to an HPR style alternator, which delivers more voltage at low rpms. Overall, Concept One is among the few companies that can customize your alternator specifications to fit high-performance applications.

High performance power steering considerations

It's not a widely known fact. A GM Type 2 pump can be adjusted to match your car's steering gear and your personal driving style. Concept One includes a GM Type 2 Power steering pump with all its serpentine drive systems. It's a compact, reliable design that can be adjusted for pressure and flow. Concept One can customize your power steering pump's characteristics to suit your steering gear and other factors like extra-wide front tires. You'll really notice the improved steering feel and feedback.

For example, a typical late 60s muscle car came with a recirculating ball steering box requiring 1300 psi operating pressure. If you're using a stock steering box, we can match the late model pump accordingly. Another example, the Gold Camaro in this article features a custom subframe with an 80s FOX body steering rack that prefers 1100 psi. With the GM Type 2 pump set at the factory 1300 psi, the steering would feel over-boosted. The extra pressure could also damage seals in the Ford steering rack. Concept One can fine-tune the pump and steering gear combination to improve reliability and your overall driving experience.

There are so many great multi-purpose hot rods running around with 500-plus horsepower small block Chevy engines these days.  It has become much easier to make power without sacrificing drivability. Any hot rod that enjoys high-performance driving events like autocross and track days should be stepped up to a true HD 8-rib Serpentine Drive System with more belt wrap, a heavy-duty tensioner, and tailored charging and drive components. If this sounds like you Concept One checks all of the boxes.

To learn more, click here:   

https://www.c1pulleys.com/products/small-block-chevy-8-rib-pulley-kit-alt-ac-ps-victory-hd