PRW 17 PRW Billet Steel Main Bearing Cap - Manual (Page 2)

could lead to distortion of the main bearing bores. Take the register depth from the block and add 0.001” to 0.003” to
determine the required side bolt pad clearance. Now, mill the caps to the proper depth. If the clearance is too large, mill
the main cap register on the bolt hole pad. If the dimension is too small, mill the outer most pad. Take great care to not cut
down the vertical register.
Step 4
Use a bottoming tap to clean up all main bolt holes in the block. Each hole should also be checked to ensure against the
possibility of the bolt bottoming out. An incorrect torque reading will result if a bolt has this problem.
Step 5
Remove all deposits, burrs, and imperfections from both the block and PRW main caps.
Step 6
Put the main caps into place on the block.
Step 7
Now install and begin to tighten down the center bolts of the caps. Do not torque them at this time.
Step 8
Insert the drill busing into the side hole of the main cap. For 3/8” bolts drill the block with a 5/16” drill bit and for 7/16”
bolts drill the block with a 3/8” bit. Be sure to drill only the bolt length plus 1/8”. Drilling to deep will put you into the
water jacket.
Step 9
After drilling, remove the drill bushing and use the cap as a guide to tap the holes. For 3/8” tap 16 threads and for 7/16”
tap 14 threads.
Step 10
Install the outside bolts to finger tight. Now, torque all inside bolts, working from the center of the block toward the ends.
Finally, torque the outside bolts working from the center towards the ends.
Step 11
Now the block is ready to be align bored. On the first pass, align bore the block with a rough cut to 0.010” under the
finished size. On the second pass bore to size. Align honing may not be needed if the boring can get close enough to size.
This will be determined after your boring is done.
Step 12
De-bur and clean up.
p:\product\installation guides\new revisions 05-11-10\PRW Billet Steel Main Bearing Caps v1.1.doc
PRW Industries, Inc.
1722 Illinois Avenue
Perris, California 92571
Tele: (951) 436-7900 FAX: (951) 928-8555
Tech: (888) 377-9779
www.prw-usa.com