Honda K20 Head Bolt Torque Specs and Sequence
Honda K20 Head Bolt Torque Specs and Sequence with application boundaries, staged tightening guidance, reuse cautions and official service-information lookup.
For the early Acura RSX K20 procedure, oil the bolt threads and under-head surfaces, tighten the ten head bolts to 39 N·m (29 lb-ft), then turn each bolt 90° and another 90° in sequence. A new factory bolt receives one additional 90° turn under this procedure.
For the early Acura RSX K20 procedure, oil the bolt threads and under-head surfaces, tighten the ten head bolts to 39 N·m (29 lb-ft), then turn each bolt 90° and another 90° in sequence. A new factory bolt receives one additional 90° turn under this procedure.
The numerical stages apply to the 2002–2005-era K20A2/K20A3 RSX procedure documented by the linked service manual. Later K20Z/K20C turbo engines, swaps, mixed K20/K24 assemblies and aftermarket studs require their exact engine-code and fastener instructions.
Interactive K20A2 / K20A3 Inline-Four center-out sequence aid
Branded downloads includedPNG and PDF exports carry the TorqueSheet logo, torquesheet.com, source-page URL, and republishing attribution request. The PDF source link is clickable.
This balanced pattern is an orientation aid; use the exact numbered manufacturer diagram for assembly.
Honda K20 Head Bolt Torque Specs
| APPLICATION / ITEM | SPECIFICATION | NOTES |
|---|---|---|
| Initial torque | 39 N·m (29 lb-ft) | Oiled factory bolts; exact sequence |
| Angle pass 1 | 90° | All ten bolts |
| Angle pass 2 | Additional 90° | All ten bolts |
| New factory bolt | One extra 90° | Only where this manual procedure applies |
| Minimum bolt diameter | 10.6 mm (0.42 in) | Replace if either measured point is smaller |
Measure every bolt at the manual's A and B points and replace it if either diameter is below 10.6 mm. If a bolt is turned beyond the specified angle, remove it and restart the installation step; do not back it off to the paint mark.
Application boundaries for K20A2 / K20A3 Inline-Four
The numerical stages apply to the 2002–2005-era K20A2/K20A3 RSX procedure documented by the linked service manual. Later K20Z/K20C turbo engines, swaps, mixed K20/K24 assemblies and aftermarket studs require their exact engine-code and fastener instructions.
Measure every bolt at the manual's A and B points and replace it if either diameter is below 10.6 mm. If a bolt is turned beyond the specified angle, remove it and restart the installation step; do not back it off to the paint mark.
Honda K20A2 / K20A3 Inline-Four specifications can change by model year, engine, platform, wheel, and installed component. Confirm the VIN or engine identity, part numbers, fastener condition, and the current manufacturer instructions before service.
Procedures used with this specification
These steps are the same for every vehicle in this family, so they are documented once rather than repeated on each page. The values above remain specific to this Honda K20A2 / K20A3 Inline-Four.
Honda K20 Head Bolt Torque Specs and Sequence FAQs
What is the head bolt torque on a Honda K20?+
For the early Acura RSX procedure: oil the bolt threads and under-head surfaces, tighten the ten head bolts to 39 N·m (29 lb-ft), then turn each bolt 90° and another 90° in sequence. A new factory bolt receives one additional 90° turn.
How do I know whether a K20 head bolt can be reused?+
Measure every bolt at the manual's A and B points and replace it if either diameter is below 10.6 mm. Reuse is decided by that measurement, not by appearance.
What if a bolt goes past its angle mark?+
Remove it and restart the installation step. Do not back it off to the paint mark — the joint has already been loaded past its specification.
Does this cover a K20Z, K20C or a swap?+
No. These stages apply to the 2002–2005-era K20A2/K20A3 RSX procedure in the linked service manual. Later K20Z and K20C turbo engines, swaps, mixed K20/K24 assemblies and aftermarket studs need their exact engine-code and fastener instructions.
Technical sources
TorqueSheet favors engine- and component-specific manufacturer instructions over unsourced universal values.
12002–2006 Acura RSX service manualFactory-format service data explicitly lists K20A2, K20A3 and K20Z1 ignition specifications and the 1-3-4-2 firing order.↗