Engine Tuning: The Power of Crower

With more than 45 years of cam grinding experience, Crower is a name to be known in the tuner aftermarket. Recently, Crower released its new line of cam cores for the Honda/Acura B18C VTEC engine. These are not regrinds of stock cores, but Crower-manufactured cores that exceed factory specs for hardness and compatibility. The process used by the company is called "chill cast" and it's the same method used by Honda for its factory camshafts. Crower offers a variety of grinds, ranging from street, street/strip to strictly race. The chill cast cores can also tolerate custom to proprietary grinds, which is another service offered by Crower.

The cams we tested were the strip grind (No. 63403), along with the dual-valve spring and titanium retainer kit (No. 84163). Due to the high lift and aggressive ramp speeds of the cams, the anticipated rpm range is above 9200 rpm, in conjunction with the spring and titanium retainer kit. The spring kit is mandatory with the 63403 to achieve a safety margin of .100 of an inch of coil bind and eliminate any unwanted weight at the valve. Tests have indicated that by going with titanium retainers, which are 6 grams lighter than stock steel units, an additional 200-300 rpm can be realized, due to better valve control.

According to Crower, "cam specs can be a mystery, unless you have some sort of cam-checking method like an EZ Cam, Adco or even a Cam Dr. program. We wanted to take the mystery out of cam comparison by testing all the specs of other manufacturer's cams like lift, duration at .050 of an inch, which happens to be the U.S. standards for measuring cams. Hopefully, other cam manufacturers will follow, which gives the public the opportunity to finally compare one particular cam with a Brand X cam."

To prevent cam spec variables (such as valve lash, rocker geometry, valve tip length and deflection), from getting in the way of measuring true cam specs, Crower's cams are measured in a cam fixture rather than through the rocker arms and valves. The lobes are actually measured at zero lash.

On the Dynamic Autosports Dynojet, the GS-R spun the rollers to a baseline on 155.2 hp and 119.9 lb-ft of torque. We decided to install a set of Crower cam gears to see what type of power changes we could incite within the powerband as well. Also added to the mix was an APEXi VAFC. For our baseline run, we decided to run the sprockets at zero degrees and the VAFC at stock specs. Once the cams were installed, power was up in the top end, but down in the mid range. In hands of dyno guru Aries Dizon, the mid range power was resolved by bumping the VTEC up to 6200 rpm using the VAFC. Dizon also discovered that the cams at zero were the best setting for this particular GS-R, but the sprockets come in handy when adding further performance parts. The vehicle power went from 155.2 hp to a whopping 172.9 hp with no power loss throughout the entire power band.