The CARRILLO connecting rod is a precision, high strength, quality connecting rod, which when properly installed and maintained, will perform flawlessly in today’s racing and high performance internal combustion engines. We would like to offer some suggestions and specifications that should be helpful in your installation.
BOLTS
All bolts should be lubricated under the heads as well as on the threads. We recommend the bolt lube included, or as an alternative, molybdenum base paste mixed with engine oil.
The preferred method to torque the bolt is by using the stretch figure listed in the table below. In order to check bolt stretch, simply fixture one rod, leaving the cap portion free from clamping load. Measure both bolt lengths loose, then progressively tighten the bolt until the measured increase in length correlates with the figures below. Use the indicated torque reading to tighten all the connecting rods in final assembly.
| THREAD |
TYPE |
HEAD
MARKING |
STRETCH
RECOMMENDED
ENGLISH |
STRETCH
RECOMMENDED
METRIC
|
TORQUE
NOT TO EXCEED
ENGLISH |
TORQUE
NOT TO EXCEED
METRIC |
| 1/4 |
CARR |
S4 |
.0040 to .0060 in |
.102 to .152 |
275 inlb |
31 Nm |
| 5/16 |
WMC |
H5 |
.0040 to .0060 in |
.102 to .152 |
38 ftlb |
52 Nm |
| 5/16 |
CARR |
S5 |
.0050 to .0070 in |
.127 to .178 |
45 ftlb |
61 Nm |
| 3/8 |
WMC |
H6 |
.0050 to .0070 in |
.127 to .178 |
45 ftlb |
61 Nm |
| 3/8 |
CARR |
S6 |
.0050 to .0070 in |
.127 to .178 |
65 ftlb |
88 Nm |
| 7/16 |
WMC |
H7 |
.0050 to .0070 in |
.127 to .178 |
75 ftlb |
102 Nm |
| 7/16-1 |
WMC |
H71 |
.0050 to .0070 in |
.127 to .178 |
75 ftlb |
102 Nm |
| 7/16 |
CARR |
S7 |
.0050 to .0080 in |
.127 to .203 |
100 ftlb |
136 Nm |
| M8 |
WMC |
HM8 |
.0040 to .0055 in |
.102 to .140 |
42 ftlb |
57 Nm |
| M8-1 |
CARR |
SM81 |
.0040 to .0055 in |
.102 to .140 |
42 ftlb |
57 Nm |
| M8 |
CARR |
SM8 |
.0045 to .0060 in |
.114 to .152 |
48 ftlb |
65 Nm |
| M9 |
WMC |
HM8 |
.0045 to .0060 in |
.114 to .152 |
60 ftlb |
81 Nm |
| M9 |
CARR |
SM9 |
.0045 to .0060 in |
.114 to .152 |
60 ftlb |
81 Nm |
Bolt Instructions