The J35 engine family, a mainstay in Honda and Acura V6 performance, rewards owners with a broad powerband and legendary reliability. While already potent from the factory, the camshafts remain one of the largest bottlenecks for airflow—especially in VTEC-equipped versions. A well-chosen performance camshaft upgrade can unlock an honest 25 horsepower at the wheels, but only when paired with proper supporting modifications and careful tuning. This expanded guide covers the specific J35 variants, camshaft selection criteria, real-world cost breakdowns, step-by-step installation insights, and the tuning strategy required to realize the full gain.

J35 Engine Variants and Camshaft Considerations

The J35 spans multiple generations across Honda and Acura models. Not all J35 engines share the same cylinder head architecture, valve angles, or VTEC actuation. Key variants include:

  • J35A (1999–2004): Found in the Acura CL, TL, and MDX. Early versions use a non-VTEC design on the intake cam only. Camshafts are smaller in diameter and use a different journal size than later engines.
  • J35Z (2005–2010): Introduced i-VTEC and variable timing. The camshafts now control the intake valves with a larger lobe profile. Aftermarket support is strong for this platform.
  • J35Y (2013–present): The earth dreams iteration with dual VTC and a higher compression ratio. Camshaft swaps are more complex due to VTC phaser integration and direct injection. Gains are often smaller unless combined with a standalone ECU.
  • J35S (2007–2013): The only J35 with a factory supercharger. Cam swaps are uncommon here, as the supercharger already masks the engine’s airflow limitations.

Before purchasing a camshaft, verify your engine code (stamped on the engine block near the transmission bell housing). The wrong camshaft will not bolt in because of journal size differences, VTEC rocker arm geometry, or timing chain pitch variations.

Types of Performance Camshafts for the J35

Three main categories exist for J35 cam upgrades. Each carries different cost, installation difficulty, and gain potential.

Reground Camshafts

A reground cam starts with a factory J35 core that is machine-ground to a new lobe profile. This is the most affordable route, usually $150–$350 per cam, but it reduces the base circle of the lobe. A smaller base circle requires adjustable cam gears or offset keys to restore proper cam timing. Regrinds also sacrifice some low-lift flow because the lobe is narrower at the base. They work best for race applications where the engine lives at high RPM.

Billet Aftermarket Camshafts

Billet cams are made from new steel stock—not a reworked factory core. Companies like Bisimoto and Crower offer drop-in J35 camshafts that maintain the correct base circle and support stock valvetrain components. These cams typically retain VTEC engagement on the high-lobe profile. Prices range from $600 to $1,200 for a pair. Gains are repeatable and require no cam gear adjustment if the manufacturer supplies the correct timing marks.

Stage Packages

A stage 1 camshaft upgrade (often called “street” or “junior”) focuses on improving mid-range torque without sacrificing idle quality. Stage 2 cams shift the powerband higher; idle becomes choppy but top-end gains exceed 25 horsepower. Stage 3 cams are for all-out race builds and mandate upgraded valve springs, retainers, and frequently a reduced compression ratio. For a street-driven J35, stage 1 or stage 2 billet cams deliver the best balance.

Detailed Cost Breakdown

The original article gave a wide range of $600–$2,300. Below is a more granular estimate based on current aftermarket pricing and common support parts.

Item Budget Option Performance Option
Camshaft set (pair) $200–$400 (regrind) $700–$1,200 (billet)
Valve springs & retainers $0 (stock can handle stage 1) $250–$450 (required for stage 2+)
Timing chain tensioner & guides $120 (replace on any cam swap) $120
Head gaskets & seals $90 (Fel-Pro set) $90
ECU tuning $300 (mail-order base tune) $600 (dyno tune)
Labor (if professional) $500–$800 $1,000–$1,500
Total $1,210–$1,710 $2,760–$3,960

Note: The “budget” column assumes you perform the installation yourself and run the camshaft on stock valve springs. If you pick a reground cam with aggressive lift, spring upgrade is mandatory to prevent valve float above 6,500 RPM.

Installation Tips for the J35 Cam Swap

Installing camshafts on the J35 is an advanced DIY project, but a competent mechanic with good tools can finish in a long weekend. Follow these expanded tips.

1. Gather Special Tools

In addition to standard wrenches and a torque wrench, the J35 requires:

  • A harmonic balancer puller (for the crank pulley)
  • Camshaft locking tools to hold the phaser or sprocket
  • Feeler gauges and a dial indicator to check lobe lift and base circle runout
  • An angled degree wheel for verifying cam timing (required for regrinds)

2. Mark Everything Before Disassembly

Chain slop hides the true relationship between the crankshaft and cams. Once the chain is off, locate the #1 piston at top dead center on the compression stroke. Mark the cam sprocket alignment with a paint marker (never a center punch—damage can cause timing chain noise). Take reference photos from multiple angles.

3. Replace Timing Chain and Tensioner

A worn timing chain will stretch 1–2 degrees under load. That stretch introduces enough error to negate the camshaft’s new lobe centerline. Install a new genuine Honda timing chain (Part number 14401-R70-A01 for most J35Z) along with the hydraulic tensioner and all guides. K-series parts retailers carry many of these J35 chain components.

4. Check VTEC Engagement Clearance

VTEC rocker arms rely on oil pressure to lock the pins. After installing new camshafts, measure the clearance between the cam lobe base circle and the rocker arm roller. If the base circle is smaller than stock (a common trait of regrinds), the rocker may bottom out on its pivot pin before the camshaft rotates—causing a hard misfire at VTEC cross-over. Use a dial indicator at the valve tip to confirm that total valve lift matches the camshaft specs.

5. Control Oil Leaks With New Seals

Camshaft swaps require removing the cam caps. Those caps are line-bored to each individual head deck; do not mix them. Install new cam tower seals, spark plug tube seals, and a fresh valve cover gasket. Apply a thin bead of Honda Bond (or equivalent anaerobic sealant) at the corners where the cam caps meet the head deck.

Tuning: The Missing Piece for 25 Horsepower Gains

A camshaft alone does not unlock the advertised 25 horsepower. The factory ECU runs a conservative fuel and ignition map calibrated for the stock valve events. A performance cam changes when the intake valve opens relative to the piston’s position. Without recalibration, the engine can lose low-end torque, run lean at high RPM, or trigger a check engine light for VTC correlation errors.

OBD2 Flash Tuning

Models with K-Engine (pre-2006 J35A) can be tuned via an OBD2 reflash from companies like Hondata or RSX-S. The tuner modifies the fuel tables and VTEC engagement point to match the new cam lobe profile. Expect to pay $400–$700 for a mail-order reflash.

Standalone ECU

For J35Z and J35Y engines, an aftermarket ECU such as the HP Tuners VCM Suite or AEM Infinity is recommended. Standalone ECUs allow full control over VTC phaser sweeps, VVT overlap, and individual cylinder fueling. The cost of the unit plus dyno time can reach $1,500–$2,500, but the result is a smooth power curve with no CELs.

Expected Gains With Supporting Mods

The 25 horsepower claim is realistic when combining the camshaft with a free-flowing intake and exhaust. On a stock intake manifold and headers, a stage 1 cam typically yields 12–15 whp. Adding a larger throttle body (maybe 70mm or 74mm) and ported intake manifold pushes the gain to 20–22 whp. The final 3–5 horsepower comes from a full exhaust system with equal-length headers and a 3-inch cat-back.

Dyno plots from shops like Speed Factory show a J35Z with Bisimoto stage 2 cams, ported heads, and long-tube headers gaining 40 horsepower at 7,000 RPM. That exceeds the 25 hp baseline because the camshaft is matched to extensive head work.

Where the Gains Appear

  • Low-end (under 2,500 RPM): Slight loss (3–5 lb-ft) with aggressive cams; stage 1 minimizes this.
  • Mid-range (3,000–5,500 RPM): +10–15 hp, noticeable daily driving feel.
  • Top-end (5,500–7,200 RPM): +20–30 hp, where the camshaft shines.

Risks and Common Pitfalls

Camshaft swaps carry real risks if not executed correctly. Valve-to-piston interference is a concern on high-compression J35Y engines. A bent valve at 7,000 RPM can destroy the entire cylinder head. Always clay-check piston-to-valve clearance after installing new camshafts—rotate the engine by hand at least two full revolutions before attempting a start.

Another frequent issue is oil starvation to the VTEC spool valve. If the cam journal clearance is too tight (very rare with billet cams but possible with regrinds that were not de-burred), the VTEC oil passage gets blocked. The result is a dull 2,500–4,500 RPM power band and a P2646 fault code. Always pre-oil the cam journals before final assembly, and check that the camshaft rotates freely after torquing the cap bolts to spec (per repair manual: 14 lb-ft for J35Z caps).

Conclusion

Upgrading the camshafts on a J35 engine is a proven path to a meaningful power increase. A budget-friendly approach using reground cams and a mail-order tune yields around 15 horsepower for about $1,500. Opting for billet cams with upgraded valvetrain, full exhaust, and dyno tuning pushes the gain past 25 horsepower—and delivers a linear, torquey powerband that transforms the driving experience. Whether you are building a daily driver or a track-focused sedan, selecting the correct camshaft profile and investing in professional installation or meticulous DIY methods ensures your J35 delivers the glory it is capable of.