Brian Crower, Inc does not recommend using synthetic oil during camshaft break-in. If you must run synthetics during operation, even though we recommend that you do not, make sure the synthetic contains a high zinc content (ZDDP count of 1400 or more). Follow OEM cam cap torque sequence and specifications. Use a liberal amount of aftermarket engine assembly lube, again with the recommended amount of zinc content, during installation and assembly. Check cam follower or bucket surfaces for any abnormal wear and/or scuffing. On initial start-up and break-in run engine at 1500-2500 rpm for 20 minutes.
Brian Crower, Inc does not recommend using any synthetic motor oil lacking zinc (ZDDP). This is especially critical with flat tappet, bucket or scrubber type finger follower camshafts (2JZ, EJ Series, B Series, SR20, etc…). Roller followers are not as critical but it is still recommended to utilize the added zinc content to prevent any premature wear.
To protect a new flat tappet, bucket or scrubber type finger follower camshaft during camshaft break-in:
To provide long-term protection for a flat tappet, bucket or scrubber type finger follower:* Use a specialty engine oil that contains high levels of ZDDP (around 1000 to 1200 ppm). Brands like JGR Driven, Shell Rotella and Chevron Delo and Brad Penn are excellent brands to source.
Note: Engine oils specifically designed for use in diesel applications will usually feature more zinc than passenger car gas engine oils. However, diesel engines are coming under greater scrutiny as well, in an effort to further reduce nationwide emissions. So, while a dedicated diesel oil may be better than a passenger car gas engine oil in terms of zinc content, you can’t automatically assume that any diesel oil contains enough ZDDP to protect a new flat-tappet cam.
Unfortunately there is no universal or magic cam gear setting that works for all applications. Tuning via adjustable cam gears comes down to driver preference with regards to idle quality, desired operating rpm range, piston to valve and valve to valve limitations as well as other considerations like power adders and stand-alone ECU capabilities. For general discussions, widening the lobe center (LC) will yield more top end performance and smooth idle characteristics. Tightening the LC will typically result in a rougher idle and deliver more bottom end torque. Gear adjustments on 2JZ, SR20, EJ Series, B Series and 4G63/Evo are as follows:
Note: It is highly recommend going a maximum of 2 marks in any direction at a time on one side (intake or exhaust) for adjustment. Any more or adjusting both intake and exhaust at the same time, may result is extensive engine damage. Cam bolt (not cam cap) torque specs for each application are as follows:
For proper rod bolt installation on Brian Crower connecting rods, please follow these important steps. Rod bolt threads and underside of bolt head should be lubricated thoroughly with supplied BC/ARP lube. Cap should be se4ated on rod by aligning cap by hand and tapping in place using a rubber mallet. Alternate tightening of bolt to avoid cocking the cap. Torque the fastener to achieve bolt stretch using the torque range below. Use a quality rod bolt stretch gauge, as improper bolt stretch will cause premature failure. If using a torque wrench sequence, torque initially to 10 ft lbs, then use one consistent pull to achieve the proper torque specification listed below:
5/16” ARP2000 Bolt Stretch = .0050” to .0055” / Torque Spec – 25-28 ft lbs
3/8” ARP2000 Bolt Stretch = .0055” to .0060” / Torque Spec – 45-50 ft lbs
3/8” ARP625+ Bolt Stretch = .0063” to .0067” / Torque Spec – 50-55 ft lbs
7/16” ARP2000 Bolt Stretch = .0055” to .0060” / Torque Spec – 65-70 ft lbs
Torque used during manufacturing: 26 ft lbs – 5/16”, 45 ft lbs – 3/8” and 70 ft lbs – 7/16”
To accurately determine the life of a fastener, it is recommended to log the fastener’s original untorqued free length and compare to free length after teardowns. If the free length increases by more than .001”, or there is any deformation or galling, the bolts must be replaced or failure could result. Fasteners are susceptible to corrosion so caution must be used when handling with bare hands or left out in the open to prevent exposure.
The dowel pin does not drive the cam gear, it is merely a locator for proper camshaft installation. If the dowel pin breaks on a camshaft, it is typically the result of a loose cam gear, a timing belt issue or some other cause not related to the dowel pin. BC offers replacement dowel pins but under no circumstances is a broken dowel pin a camshaft warranty issue.
If replacing your valves, especially if going with larger than stock head diameter, please verify the installed height if you are having issues with setting recommended valve lash or are seeing abnormal wear on rocker pads or buckets. If the valve is seated too short it would cause the lash to be tighter or, on rockers, to wear to the outside of the contact surface. If seated too deep, lash would be looser or, again on rockers, the wear would be on the inside of the contact surface. This will also impact rocker ratio figures in finger follower type applications. A handy way to check geometry is to put dykem on the wear pads or bucket and spin the cam over by hand and the wear pattern should be in the center. The wear pattern should never leave the contact surface or it will cause rocker/bucket and/or camshaft failure.
To measure valve installed height, use a pair of calipers or 6 inch scale and measure from the bottom of the spring seat to the top of the keeper groove. You can seat the retainer and keepers on the valve (no spring) to get an accurate reading. It is critical that you maintain OEM/stock installed height or severe damage could occur. All valve spring specs are based off of the factory installed height, including whether the valve spring can accommodate maximum camshaft lift.