Street, strip, domestic, import, NASCAR, INDY... Crower makes a part for almost anything powered by a four-stroke gas engine. With a name like Crower Cams & Equipment, one would think they would have made a camshaft for the Honda market years ago. For your information, Crower has been regrinding cams for Hondas for quite some time, but what you didn't know was it has been designing a cam profile for VTEC enthusiasts that is chill-cast and Crower-spec. The big advantage--no core charge!
For about a year now, Crower has been dabbling in chill-cast replacement cams for Honda DOHC VTECs. One of the biggest hinderances to making a camshaft from scratch is matching the metal hardness to that of the factory camshafts. This is a very critical factor that must be achieved in order to prevent premature wear.
After a year of worn cam lobes and rocker arm lash pads, Crower has finally come up with a unit that has withstood the company's R&D torture tests. Ensuring the material is equivalent to the OEM material, Crower's R&D department bench-tested the cams days at a time, at different ranges of engine speeds. With the hard part out of the way, the R&D crew was ready to tackle the task of designing a grind superior to others on the market.
The foundation for the camshaft was based on the very popular Civic Si, so working in compliance with the dreadful OBD-II was a must in order to suit the needs of daily-driven racers. Crower advised us the camshafts reveal their best power with the company's titanium retainers, valve springs and cam sprockets.
Since Crower's test vehicle was a '99 Civic Si, we also used a '99 Civic Si as a test bed for the finished product. The vehicle was equipped with air intake, exhaust system and header, which baselined 144 hp and 106 lbs-ft of torque. With the basic upgrades complete, we augmented the Si with a set of Crower bumpsticks, springs and cam sprockets.
According to marketing director Brian Crower, "The camshafts make great power, but degreeing the cam to your specific application with a set of adjustable cam sprockets will reveal all the available power within the cams." We found this to be true on the dyno, when it came down to dialing in the right cam timing for our Si. Some information worth considering is timing differences from one car to another. Issues dealing with timing belt wear, milled heads or decked blocks can throw timing off a great deal, so our only way to fix this is to utilize adjustable cam sprockets. Fortunately for us, our Si had very low mileage. With the intake cam advanced 3 degrees and the exhaust at 1.5 degrees, we were able to extract 10.5 ponies out of the 1.6-liter. Considering most of the power was gained in the mid-range as well as the top-end, the Crower cams can generate plenty of power, if tuned right. In the end, the Civic hit a peak of 154.4 horsepower and 116.5 lbs-ft of torque.
A year in the making and Crower's new 63401 has passed the rigorous torture tests to invoke plenty of VTEC power. The best part about the whole deal is there is no core charge. Match these up with the rest of the Crower import arsenal and your Si should have plenty of kick-ass power.
Slip the timing belt off the...
Slip the timing belt off the cam sprockets and remove the three 12mm bolts that hold the distributor in place.
Loosen all 12mm and 10mm bolts...
Loosen all 12mm and 10mm bolts holding the intake and exhaust cam covers to access the cam journals. With the covers removed, remove the cam journals. Be sure that journal number five retains the dowel, plus the O-ring located in the bottom center of the journal.
The cam bolts, keys and oil...
The cam bolts, keys and oil seals need to be removed from the OE camshafts and installed on the new Crower 63401 cams. Since the 14mm bolts were loosened previously they should free up easily.
All Crower cams come with...
All Crower cams come with special break-in lube that must be applied to the lobe surfaces as well as the cam journals.
Place the cams into the head...
Place the cams into the head while lining up the cam timing marks as close as you can to their original TDC mark. The cams will not sit at their exact TDC mark, so they must be set once the cam journals are installed.
As explained earlier, with...
As explained earlier, with the cam journals torqued down, the cams can now be set at their TDC mark. Once the timing is correct, the timing belt can then be slipped back on to the sprockets. Using a 19mm socket, crank the engine over by hand counter clockwise. Watch the sprocket while cranking to be sure the degree marks move from 12:00, stopping at 10:00. Once this is accomplished, tighten back down on the 14mm tensioner bolt.
Reinstall the cam covers with...
Reinstall the cam covers with bolts and torque all the 12mm bolts to 20 lbs-ft and 10mm to 9 lbs-ft. Also, make sure all the bolts are tightened in there proper torque sequence.
Valve adjustment is very critical...
Valve adjustment is very critical for proper performance output so all adjustments must be followed in the same order as the factory adjustment minus the factory valve lash specification. Use a factory service manual for adjustment procedures.
To make the final cam adjustments...
To make the final cam adjustments we decided to cut the sprocket cover section off the valve cover. This allows one to adjust the cam timing with the valve cover still bolted to the head of the engine.
Distributor timing should...
Distributor timing should always be adjusted whenever the intake cam timing is adjusted. In our case we set initial distributor timing to 19 degrees.
Camology 101
How To Read A Cam Card
Why the heck would you want to read a cam card?! Better yet, how do you read a cam card?! When you purchase a cam, a cam card is provided to help the installer understand more about the cam set-up. This usually gets thrown out with the box the cam came in, because most of the time the cam you purchased is a tried-and-true product. Since knowledge is power, we compiled the following cam card guidelines to help you better understand what it is you just purchased. This is vital information, because there is a lot more to a camshaft than lift and duration.
A: Intake & Exhaust Duration: This is measured in degrees of how long the valves are open. This number is rated at the camshaft and end result will be the same at the valve.
B: Intake & Exhaust Lift: This is measured in inches and in most cases this number refers to the valve lift and not cam lift. Valve lift is the measurement at the valve side of the rocker arm. This number is a calculation of cam lift with rocker ratio figured into the equation. (See D rocker ratio)
C: Intake & Exhaust Clearances: This is the recommended valve lash for these particular cams. The measurement is given in inches and the card explains that measurements should be done with the engine cold.
D: Rocker Ratio: The rocker ratio is the proportional relationship between measured lift at the cam and measured lift at the valve based on a rocker arms fulcrum point.
E: Duration @ .050: This is the U.S. standard of measurement. U.S.-spec cams are measured at .050 thousands of an inch.
F: Lobe Lift: This is the actual lift of the cam without the rocker ratio calculated into the equation. Cam lift is figured by measuring the cam from the tip of its ramp to the bottom of the base circle. Then measuring the base circle and subtracting the base circle measurement from the tip-to-base measurement.
G: Lobe Center: This is also referred to as lobe separation angle. Lobe center is measured in degree comparisons between the intake lobes and the exhaust lobes from the center of the camshaft. Since most imports are DOHC this number can be tailored with the use of cam sprockets. DOHC engines have two centers because of the use of two cams. Since changing the degrees on the cams can widen or shorten the lobe separation angle this number is often ignored. On single-cam engines this number is fixed since the intake and exhaust lobes are on the same shaft.
Removing the 10mm nuts and...
Removing the 10mm nuts and spark plug wires allows access to the camshafts.
Double check that the crank...
Double check that the crank and cams are at top dead center before the timing belt is removed. Our vehicle was outfitted with Crower Cam sprockets, but the TDC marks resemble the factory sprocket marks. To make your job much easier, loosen the two 14mm sprocket bolts while there is still tension on the belt.
Loosen the 14mm tensioner...
Loosen the 14mm tensioner bolt. This bolt can be found between the crank pulley and the cam gears. Do not remove the bolt completely, just enough so the belt becomes loose on the right-hand side of the timing belt.