Engine Specs - S65/S85 Rod Bolts

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Which rod bolts are best?

A lot of people ask which connecting rod bolts are best, and which they should use.  There is no simple answer.  Factory bolts cost less but take longer to install.  Once you use them, you need to throw them away and buy new ones.  Aftermarket bolts cost significantly more (3x, 4x) than factory bolts, but they take less time to install and can be reused.

While there is no doubt aftermarket rod bolts will be higher quality and stronger than factory bolts, they also have some side-effects that most people don't realize.

Clamping force

The ability to keep the rod bore perfectly round will depend on the clamping strength of the rod bolt itself.  Believe it or not, all rod bolts when torqued to specifications do not have the same clamping force.  To keep the rod bore round will depend on keeping the rod bolts at the same clamping force.  You can assume the factory rod bolts when torqued to factory specifications will do the job correctly.  But the same can't be said for the aftermarket rod bolts as we shall see below.

Rod bore distortion

The rod bolts play a critical role in keeping the rod big-end bore perfectly round. A properly torqued rod bolt and properly honed rod big-end bore will create a perfectly round circle in the big-end bore. The clamping force is what creates this perfect circle. With improper clamping force, the rod big-end bore will distort, and become out of round.

You may ask whether or not this matters. Yes, of course it matters. The rod bearing itself is not perfectly round. The rod bearing is designed to be thinner on the sides and thicker in the center. This design maximizes the oil wedge strength at 90-degrees to the parting lines (Top-Dead-Center) when the bearing needs it most. To ensure the bearing works correctly to maximize film strength, the rod bore big it must be as perfectly round as possible. When the bore is not round, we call this bore distortion. Bore distortion in either direction can cause bearing failure. Both the Mahle and King bearing failure guides show examples of bearing failure caused by this type of bore distortion. The following two guides explain bearing eccentricity, bore distortion, and bearing failures in far greater detail than I ever could.

PDF Guide: Optimal Eccentricity for High Performance Bearings

PDF Guide: Mahle Bearing Failure Guide

In theory, whenever the rod bolts are changed, the rod big-end should be re-honed to reestablish the perfect circle of the bore. Re-honing the connecting rod is essential because the clamping force of the new rod bolts will be different. But in reality when people change their rod bearings and install new rod bolts, they can't re-hone the connecting rods because it would require complete engine disassembly. So selecting to correct rod bolt with the correct torque is essential to matching as closely as possible the original factory clamping force. It's not going to be perfect, but it will be good enough.

Brand new BMW factory rods have a bit of bore distortion of their own. BMW factory hones the rods with rod bolts at approximately 2/3 of their factory torque specification. When measured in this configuration, the rod big-end bore is as perfectly round as it should be. When you torque the bolts to their proper specification, then a brand new factory connecting rod will have a bit of <negative> bore distortion. After use in an engine, the rods will stretch with the rod bearings and new clamping force; the result is a pretty round bore after new rod bolts are installed.

Here's an example of brand new (virgin) connecting rods with virgin rod bolts. These were honed with rod bolts at 2/3 torque spec. When fully tightened, the virgin connecting rods have the following bore distortion. Caption
Virgin rod with Virgin rod bolts

As I mentioned above, lightly used or remanufactured rods have virtually no big-end bore distortion. Here's an example of remanufactured rods that were honed while the rod bolts were correctly tightened. Notice virtually perfectly round bore: no bore distortion.

OEM-Rod-Bolt-Eccentricity.jpg
OEM Rod Bolt Bore Distortion

Without the correct clamping force, the rod big-end will distort. This is particularly obvious when aftermarket connecting rod bolts are used. The ARP-2000 and ARP-625 rod bolts are superior quality to OEM connecting rods, but they have a different clamping force than factory rods. Because of this different clamping force, they distort the bore.

Here's an example of an ARP-2000 rod bolt, on a brand new (virgin) connecting rod. This is the same virgin connecting rod shown above. The only difference is the installation of the ARP-2000 connecting rod bolts properly torqued to the manufacture's specification (45 ft/lbs).

Virgin-Rod OEM-Rod-Bolt ARP-2000 Eccentricity.jpg
ARP-2000 Rod Bolt Bore Distortion

Notice in the graph above there is quite a difference between the factory rod bolts and ARP-2000's. Both rod bolts are torqued to specification, but the shape of the bore hole is vastly different. The following graph will help illustrate only the difference between them. This graph shows the difference between the OEM and ARP-2000 rod bolts. Notice in this graph, there is up to 0.0008 difference at 90-degrees.

Virgin-Rod Delta ARP-2000 Eccentricity.jpg
Delta: ARP-2000 Rod Bolt Bore Distortion


Rod Bolt Comparisons

OEM Rod Bolts

SPEC: OEM: Torque procedure

Torque Angle
20 Nm 130 degrees
Release bolts  
20 Nm 130 degrees
Release bolts  
20 Nm 130 degrees


Make sure you are starting with new rod bolts.  Factory rod bolts must be replaced once used.

  1. Lubricate rod bolt threads and connecting rod cap bore holes with appropriate thread lubricant.
  2. Torque to 20-Nm, then using a torque-angle gauge tighten another 130-degrees.
  3. Release bolts.
  4. Repeat steps 1-3
  5. Repeat steps 1, 2.

SPEC: OEM: Clamping Force

  • Clamping Force: Approximately 11000 pounds force.

SPEC: OEM: Measurements (Virgin Rods)

  • Virgin rods are honed at approximately 2/3 torque. When the rod bolts are tightened to full torque, the virgin rods distort the bore by making the measurements at 90-degrees a few tenths tighter than perfectly round. For factory bearings, this might be a problem. For aftermarket extra-clearance bearings from BE Bearings, this is not a problem.

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20470 2.20480 2.20480 2.20480 2.20475 2.20500 2.20480 2.20470
19.75 2.20470 2.20480 2.20470 2.20480 2.20475 2.20480 2.20480 2.20480
45.00 2.20460 2.20480 2.20465 2.20470 2.20460 2.20465 2.20470 2.20470
90.00 2.20440 2.20460 2.20450 2.20460 2.20460 2.20440 2.20465 2.20465
135.00 2.20440 2.20450 2.20460 2.20460 2.20460 2.20460 2.20465 2.20460
160.25 2.20460 2.20460 2.20480 2.20465 2.20475 2.20480 2.20470 2.20470
175.00 2.20470 2.20480 2.20480 2.20475 2.20470 2.20480 2.20480 2.20470

SPEC: OEM: Bore Distortion (Virgin Rods)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 -0.00005 -0.00010 -0.00005 -0.00005 0.00003 -0.00010 -0.00005 0.00005
45.00 -0.00020 -0.00015 -0.00018 -0.00013 -0.00012 -0.00028 -0.00013 -0.00005
90.00 -0.00030 -0.00020 -0.00030 -0.00018 -0.00012 -0.00050 -0.00015 -0.00005
135.00 -0.00020 -0.00015 -0.00018 -0.00013 -0.00012 -0.00028 -0.00013 -0.00005
160.25 -0.00005 -0.00010 -0.00005 -0.00005 0.00003 -0.00010 -0.00005 0.00005
175.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000


Virgin-Rod OEM-Rod-Bolt-Eccentricity.jpg

SPEC: OEM: Measurements (Remanufactured Rods)

  • Remanufactured rods are honed at full rod bolt torque. This ensures a virtually perfect round bore.

Measurement Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20495 2.20500 2.20510 2.20510 2.20500 2.20510 2.20495 2.20500
19.75 2.20500 2.20490 2.20500 2.20510 2.20500 2.20510 2.20480 2.20500
45.00 2.20500 2.20480 2.20500 2.20495 2.20500 2.20490 2.20480 2.20490
90.00 2.20520 2.20480 2.20500 2.20480 2.20520 2.20490 2.20480 2.20500
135.00 2.20520 2.20490 2.20500 2.20480 2.20510 2.20500 2.20490 2.20490
160.25 2.20510 2.20490 2.20500 2.20500 2.20510 2.20500 2.20490 2.20500
175.00 2.20500 2.20500 2.20500 2.20500 2.20500 2.20500 2.20480 2.20500

SPEC: OEM: Bore Distortion (Remanufactured Rods)

Measurement Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 0.00007 -0.00010 -0.00005 0.00000 0.00005 0.00000 -0.00003 0.00000
45.00 0.00012 -0.00015 -0.00005 -0.00017 0.00005 -0.00010 -0.00003 -0.00010
90.00 0.00022 -0.00020 -0.00005 -0.00025 0.00020 -0.00015 -0.00008 0.00000
135.00 0.00012 -0.00015 -0.00005 -0.00017 0.00005 -0.00010 -0.00003 -0.00010
160.25 0.00007 -0.00010 -0.00005 0.00000 0.00005 0.00000 -0.00003 0.00000
175.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000


OEM-Rod-Bolt-Eccentricity.jpg


ARP-2000 rod bolts

ARP-2000 rod bolts are a step up in strength and quality from OEM factory bolts. These bolts for S65/S85 are custom made by ARP for VAC Motorsports. ARP does not manufacture and sell these bolts to the public. You can only get these through VAC Motorports.

ARP-2000 rod bolts are also available from BE Bearings. We call these BE-ARP. These bolts for S65/S85 are custom made by ARP for BE Design (aka BE Bearings). The BE-ARP rod bolts have been thoroughly tested at different torque ratings to ensure the best setting to match OEM clamping force with minimum bore distortion. ARP does not manufacture and sell these bolts to the public. You can only get these through the BE Bearings web store @ http://www.bebearings.com/store, or a BE Bearings reseller.

SPEC: ARP-2000: Torque Procedure

  • 45 ft-lbs (VAC).
  • 50 ft-lbs (BE-ARP).
  • Unlike the factory rod bolts, these may be reused.

SPEC: ARP-2000: Clamping force

  • TBD

SPEC: ARP-2000: Measurements (Virgin Rods, 45 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20480 2.20480 2.20495 2.20480 2.20460 2.20490 2.20480 2.20460
19.75 2.20495 2.20490 2.20480 2.20495 2.20480 2.20500 2.20500 2.20480
45.00 2.20500 2.20495 2.20500 2.20500 2.20485 2.20495 2.20500 2.20500
90.00 2.20490 2.20490 2.20500 2.20500 2.20500 2.20495 2.20510 2.20510
135.00 2.20480 2.20480 2.20495 2.20480 2.20490 2.20495 2.20495 2.20500
160.25 2.20480 2.20480 2.20500 2.20480 2.20480 2.20490 2.20495 2.20480
175.00 2.20470 2.20480 2.20495 2.20480 2.20460 2.20480 2.20480 2.20460

SPEC: ARP-2000: Bore Distortion (Virgin Rods, 45 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 0.00013 0.00005 -0.00005 0.00008 0.00020 0.00010 0.00018 0.00020
45.00 0.00015 0.00008 0.00002 0.00010 0.00027 0.00010 0.00018 0.00040
90.00 0.00015 0.00010 0.00005 0.00020 0.00040 0.00010 0.00030 0.00050
135.00 0.00015 0.00008 0.00002 0.00010 0.00027 0.00010 0.00018 0.00040
160.25 0.00013 0.00005 -0.00005 0.00008 0.00020 0.00010 0.00018 0.00020
175.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000


  • Rod bolt bore distortion comparison: ARP-2000 rod bolts vs. OEM rod bolts

Virgin-Rod OEM-Rod-Bolt ARP-2000 Eccentricity.jpg

  • Difference between ARP-2000 rod bolts vs. OEM rod bolts

Virgin-Rod Delta ARP-2000 Eccentricity.jpg

SPEC: ARP-2000: Measurements (Virgin Rods, 50 Ft/Lbs)

Measurement Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20490 2.20490 2.20495 2.20490 2.20485 2.20500 2.20500 2.20485
19.75 2.20500 2.20490 2.20480 2.20490 2.20485 2.20490 2.20485 2.20485
45.00 2.20475 2.20480 2.20475 2.20475 2.20485 2.20475 2.20470 2.20460
90.00 2.20460 2.20460 2.20475 2.20460 2.20470 2.20460 2.20460 2.20460
135.00 2.20460 2.20460 2.20480 2.20460 2.20460 2.20460 2.20480 2.20460
160.25 2.20470 2.20470 2.20490 2.20485 2.20490 2.20485 2.20495 2.20480
175.00 2.20480 2.20490 2.20500 2.20490 2.20490 2.20495 2.20495 2.20480

SPEC: ARP-2000: Bore Distortion (Virgin Rods, 50 Ft/Lbs)

Measurement Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 0.00000 -0.00010 -0.00013 -0.00002 0.00000 -0.00010 -0.00007 0.00000
45.00 -0.00018 -0.00020 -0.00020 -0.00022 -0.00015 -0.00030 -0.00023 -0.00022
90.00 -0.00025 -0.00030 -0.00022 -0.00030 -0.00018 -0.00038 -0.00038 -0.00022
135.00 -0.00018 -0.00020 -0.00020 -0.00022 -0.00015 -0.00030 -0.00023 -0.00022
160.25 0.00000 -0.00010 -0.00013 -0.00002 0.00000 -0.00010 -0.00007 0.00000
175.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000


  • Rod bolt bore distortion comparison: ARP-2000 rod bolts vs. OEM rod bolts

ARP-2000 Eccentricity vs OEM.jpg

  • Difference between ARP-2000 rod bolts vs. OEM rod bolts

ARP-2000 Eccentricity-Delta 45-50-ftlbs.jpg

SPEC: ARP-2000: Measurements (Remanufactured Rods, 45 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20480 2.20480 2.20480 2.20475 2.20480 2.20475 2.20475 2.20485
19.75 2.20510 2.20500 2.20510 2.20510 2.20520 2.20515 2.20515 2.20500
45.00 2.20560 2.20515 2.20540 2.20560 2.20540 2.20545 2.20545 2.20530
90.00 2.20600 2.20540 2.20565 2.20580 2.20575 2.20575 2.20580 2.20560
135.00 2.20580 2.20520 2.20540 2.20560 2.20540 2.20545 2.20555 2.20545
160.25 2.20520 2.20500 2.20500 2.20500 2.20495 2.20510 2.20520 2.20520
175.00 2.20480 2.20480 2.20475 2.20470 2.20480 2.20480 2.20480 2.20490

SPEC: ARP-2000: Bore Distortion (Remanufactured Rods, 45 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 0.00035 0.00020 0.00027 0.00033 0.00027 0.00035 0.00040 0.00022
45.00 0.00090 0.00038 0.00062 0.00088 0.00060 0.00067 0.00072 0.00050
90.00 0.00120 0.00060 0.00087 0.00108 0.00095 0.00097 0.00102 0.00073
135.00 0.00090 0.00038 0.00062 0.00088 0.00060 0.00067 0.00072 0.00050
160.25 0.00035 0.00020 0.00027 0.00033 0.00027 0.00035 0.00040 0.00022
175.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000


  • ReMfg Rods: Rod bolt bore distortion comparison: ARP-2000 rod bolts vs. OEM rod bolts

ARP2000-Rod-Bolt-Eccentricity.jpg

  • ReMfg Rods: Difference between ARP-2000 rod bolts vs. OEM rod bolts

ARP-2000 ReMfg Eccentricity-Delta 45-ftlbs.jpg


ARP-625 rod bolts

SPEC: ARP-625: Torque Procedure

  • 60 Ft/Lbs
  • Unlike the factory rod bolts, these may be reused.

SPEC: ARP-625: Clamping force

  • TBD

SPEC: ARP-625: Measurements (Virgin Rods, 60 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20515 2.20500 2.20490 2.20500 2.20500 2.20520 2.20515 2.20500
19.75 2.20490 2.20490 2.20490 2.20480 2.20490 2.20500 2.20490 2.20470
45.00 2.20440 2.20460 2.20450 2.20440 2.20440 2.20460 2.20460 2.20440
90.00 2.20420 2.20420 2.20460 2.20420 2.20420 2.20430 2.20440 2.20420
135.00 2.20425 2.20420 2.20470 2.20430 2.20440 2.20460 2.20450 2.20440
160.25 2.20460 2.20475 2.20480 2.20475 2.20485 2.20480 2.20480 2.20465
175.00 2.20500 2.20500 2.20500 2.20520 2.20500 2.20500 2.20515 2.20495

SPEC: ARP-625: Bore Distortion (Virgin Rods, 60 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 -0.00033 -0.00018 -0.00010 -0.00032 -0.00013 -0.00020 -0.00030 -0.00030
45.00 -0.00075 -0.00060 -0.00035 -0.00075 -0.00060 -0.00050 -0.00060 -0.00057
90.00 -0.00087 -0.00080 -0.00035 -0.00090 -0.00080 -0.00080 -0.00075 -0.00077
135.00 -0.00075 -0.00060 -0.00035 -0.00075 -0.00060 -0.00050 -0.00060 -0.00057
160.25 -0.00033 -0.00018 -0.00010 -0.00032 -0.00013 -0.00020 -0.00030 -0.00030
175.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000


  • Rod bolt bore distortion comparison: ARP-625 rod bolts @ 60 Ft/Lbs vs. OEM rod bolts

ARP-625 Eccentricity 60-ftlbs vs OEM.jpg

  • Difference between ARP-625 rod bolts @ 60 Ft/Lbs vs. OEM rod bolts

ARP-625 Eccentricity-Delta 60-ftlbs.jpg

SPEC: ARP-625: Measurements (Virgin Rods, 55 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20510 2.20510 2.20500 2.20515 2.20510 2.20530 2.20515 2.20500
19.75 2.20500 2.20500 2.20490 2.20500 2.20500 2.20510 2.20500 2.20480
45.00 2.20460 2.20475 2.20485 2.20460 2.20460 2.20475 2.20475 2.20470
90.00 2.20440 2.20440 2.20460 2.20440 2.20460 2.20440 2.20460 2.20460
135.00 2.20440 2.20440 2.20475 2.20465 2.20460 2.20485 2.20460 2.20460
160.25 2.20475 2.20485 2.20490 2.20500 2.20485 2.20490 2.20500 2.20475
175.00 2.20500 2.20500 2.20500 2.20515 2.20500 2.20510 2.20510 2.20500

SPEC: ARP-625: Bore Distortion (Virgin Rods, 55 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 -0.00017 -0.00012 -0.00010 -0.00015 -0.00012 -0.00020 -0.00012 -0.00022
45.00 -0.00055 -0.00047 -0.00020 -0.00053 -0.00045 -0.00040 -0.00045 -0.00035
90.00 -0.00065 -0.00065 -0.00040 -0.00075 -0.00045 -0.00080 -0.00052 -0.00040
135.00 -0.00055 -0.00047 -0.00020 -0.00053 -0.00045 -0.00040 -0.00045 -0.00035
160.25 -0.00017 -0.00012 -0.00010 -0.00015 -0.00012 -0.00020 -0.00012 -0.00022
175.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000


  • Rod bolt bore distortion comparison: ARP-625 rod bolts @ 55 Ft/Lbs vs. OEM rod bolts

ARP-625 Eccentricity 60,55-ftlbs vs OEM.jpg

  • Difference between ARP-625 rod bolts @ 55 Ft/Lbs vs. OEM rod bolts

ARP-625 Eccentricity-Delta 60-55-ftlbs.jpg

SPEC: ARP-625: Measurements (Virgin Rods, 50 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20510 2.20510 2.20500 2.20510 2.20500 2.20535 2.20500 2.20500
19.75 2.20500 2.20500 2.20500 2.20500 2.20495 2.20520 2.20500 2.20480
45.00 2.20480 2.20480 2.20495 2.20480 2.20485 2.20480 2.20480 2.20480
90.00 2.20460 2.20460 2.20480 2.20460 2.20475 2.20470 2.20470 2.20460
135.00 2.20460 2.20460 2.20480 2.20470 2.20470 2.20480 2.20480 2.20470
160.25 2.20480 2.20490 2.20500 2.20500 2.20480 2.20500 2.20495 2.20480
175.00 2.20510 2.20520 2.20500 2.20515 2.20500 2.20520 2.20510 2.20495

SPEC: ARP-625: Bore Distortion (Virgin Rods, 50 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 -0.00020 -0.00020 0.00000 -0.00012 -0.00012 -0.00018 -0.00007 -0.00018
45.00 -0.00040 -0.00045 -0.00012 -0.00038 -0.00023 -0.00048 -0.00025 -0.00023
90.00 -0.00050 -0.00055 -0.00020 -0.00052 -0.00025 -0.00058 -0.00035 -0.00038
135.00 -0.00040 -0.00045 -0.00012 -0.00038 -0.00023 -0.00048 -0.00025 -0.00023
160.25 -0.00020 -0.00020 0.00000 -0.00012 -0.00012 -0.00018 -0.00007 -0.00018
175.00 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000 0.00000


  • Rod bolt bore distortion comparison: ARP-625 rod bolts @ 50 Ft/Lbs vs. OEM rod bolts

ARP-625 Eccentricity 60,55,50-ftlbs vs OEM.jpg

  • Difference between ARP-625 rod bolts @ 50 Ft/Lbs vs. OEM rod bolts

ARP-625 Eccentricity-Delta 60-55-50-ftlbs.jpg


Carrillo-WMC Rod Bolts

SPEC: Carrillo-WMC: Torque Procedure

  • 45 Ft/Lbs
  • Unlike the factory rod bolts, these may be reused.

SPEC: Carrillo-WMC: Clamping force

  • 8150 Pounds pressure

SPEC: Carrillo-WMC: Measurements (Virgin Rods, 45 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 2.20465 2.20475 2.20460 2.20440 2.20480
19.75 2.20480 2.20480 2.20490 2.20480 2.20480
45.00 2.20520 2.20500 2.20515 2.20530 2.20500
90.00 2.20510 2.20510 2.20520 2.20560 2.20410
135.00 2.20480 2.20500 2.20495 2.20520 2.20410
160.25 2.20480 2.20480 2.20480 2.20460 2.20495
175.00 2.20470 2.20490 2.20470 2.20440 2.20480

SPEC: Carrillo-WMC: Bore Distortion (Virgin Rods, 45 Ft/Lbs)

Angle Rod-1 Rod-2 Rod-3 Rod-4 Rod-5 Rod-6 Rod-7 Rod-8
5.00 0.00000 0.00000 0.00000 0.00000 0.00000
19.75 0.00013 -0.00002 0.00020 0.00030 0.00008
45.00 0.00033 0.00018 0.00040 0.00085 -0.00025
90.00 0.00042 0.00027 0.00055 0.00120 -0.00070
135.00 0.00033 0.00018 0.00040 0.00085 -0.00025
160.25 0.00013 -0.00002 0.00020 0.00030 0.00008
175.00 0.00000 0.00000 0.00000 0.00000 0.00000


  • Rod bolt bore distortion comparison: Carrillo-WMC rod bolts @ 45 Ft/Lbs vs. OEM rod bolts

Carrillo-WMC Eccentricity 45-ftlbs vs OEM.jpg

  • Difference between Carrillo-WMC rod bolts @ 45 Ft/Lbs vs. OEM rod bolts

Carrillo-WMC Eccentricity-Delta 45-ftlbs.jpg