Civic SI Build
A 2009 Honda Civic SI (FG2) coupe with the K20Z3 engine — bolt-on modifications, maintenance scheduling, and performance tuning, all tracked in git like a software project.
The Platform
The 8th generation Civic SI coupe (2006–2011) came with the K20Z3 — a 2.0L i-VTEC inline-four producing 197hp and 139 lb-ft from the factory. Paired with a close-ratio 6-speed manual, it's one of the last naturally aspirated, high-revving Honda platforms before the turbo era.
This build sits at around 170k miles. The approach is methodical: address reliability first, upgrade the drivetrain to handle more power, then layer on the performance parts. Every modification, maintenance task, and part decision is documented and version-controlled.
Installed Modifications
Exedy Stage 1 Clutch
Exedy Stage 1 Organic (08806) clutch kit paired with the HF02 flywheel. Handles increased torque while maintaining a streetable pedal feel and smooth engagement.
K&N Typhoon Intake
K&N Typhoon 69-1014TS cold air intake. Replaces the restrictive factory airbox with a short-ram design and high-flow filter for better throttle response.
Acuity Short Shifter
Acuity 3-way adjustable short shifter with transmission-side bushings. Cuts shift throw significantly and tightens up the gate feel across all six gears.
Continental DWS06 Plus
Continental ExtremeContact DWS06 Plus all-season performance tires. Strong dry and wet grip with predictable breakaway characteristics.
Planned Modifications
Engine & ECU
- Hondata FlashPro — ECU calibration and real-time datalogging
- Skunk2 Alpha header + Berk HFC — exhaust flow improvements
- Skunk2 Ultra Street intake manifold — improved runner design
- ATI Super Damper + NST underdrive pulleys — harmonic dampening and reduced parasitic loss
- Flex fuel kit — E85 capability for additional power
Brakes & Suspension
- Hawk HPS pads + R1 Concepts slotted rotors — improved stopping power
- BC Racing BR coilovers — adjustable ride height and damping
- Full suspension overhaul — control arms, end links, bushings
Drivetrain & Exhaust
- QTP electric exhaust cutout — valved exhaust, DIY install
- Hybrid Racing 70A engine mounts — reduced drivetrain slop
- Hybrid Racing CMC kit — hydraulic clutch master upgrade
Tech
- LattePanda 3 Delta — in-car PC for datalogging, diagnostics, and media
Why Git?
Car builds accumulate decisions over months and years — part numbers, torque specs, install notes, what worked, what didn't. Tracking it all in a git repository means every change is versioned, searchable, and diffable. Install guides live alongside the build log. Part research is preserved even if plans change.
The repo includes a Python PDF generator that compiles the build documentation into printable format for the garage.