Why Upgrade to a Toda Racing Camshaft for Your J-Series Engine

The J-series family of V6 engines—found in the Honda Accord, Acura TL, MDX, and many other models—is known for reliability and a broad powerband. However, factory camshaft profiles prioritize fuel economy and emissions over peak power. A Toda Racing camshaft changes that. These aftermarket cams feature increased lift and longer duration, allowing the engine to breathe more freely at high RPM. The result is a noticeable gain in peak horsepower (typically 15–25 whp on an otherwise stock J35 or J37) and an improved torque curve that pulls harder through the mid- to upper range.

Toda Racing, a Japanese brand with decades of Honda-specific experience, grinds their J-series camshafts from chilled cast iron and profiles them to work with stock valve springs for milder street applications, or with upgraded springs for aggressive race cams. This guide focuses on the street-oriented “A” and “B” spec camshafts, which are popular for daily-driven performance cars. Whether you’re building a naturally aspirated J-series or laying the groundwork for forced induction, installing a Toda camshaft is a proven way to unlock hidden potential.

What You’ll Need Before Starting

Gather all parts and tools before you begin. Having everything on hand prevents interruptions and ensures a clean workflow.

Parts & Consumables

  • Toda Racing camshaft (part number varies by J-series variance) – order for your specific engine code (J35A, J35Z, J37A, etc.). Toda offers cam-only kits and packages with valve springs.
  • New timing belt and tensioner – while you have the timing cover off, replace the belt. J-series timing belts are interference; a failed belt can destroy valves.
  • Valve cover gasket set – includes gaskets, spark plug tube seals, and rubber grommets. Always replace these when the valve covers are off.
  • Front camshaft seal (right bank) and rear seal (left bank) – part numbers 91213-R70-A01 and 91214-R70-A01 respectively.
  • Engine oil and filter – 5W-30 or 10W-30 high-quality synthetic is recommended for break-in.
  • Honda Bond HT or equivalent gasket sealant – for the timing cover and valve cover seams.
  • RTV silicone (black or grey) – small tube for minor sealing points.
  • Brake cleaner or degreaser – for cleaning mating surfaces.

Tools

  • Metric socket set (8mm–19mm deep and shallow)
  • Torque wrench (ft-lb and in-lb ranges)
  • Timing belt tool kit (crankshaft pulley holder, cam gear holding tool)
  • Jack and jack stands
  • Floor jack and front wheel ramps (optional but helpful)
  • Pry bar (small, for releasing tensioner)
  • Feeler gauge (for checking valve lash if using adjustable cam gears)
  • Safety glasses and mechanic’s gloves
  • Shop towels and a parts tray

Preparation – Set Up for Success

1. Cool down the engine. Work on a cold engine (overnight cold is best) to avoid burns and ensure accurate torque readings on warm aluminum components.

2. Disconnect the battery. Remove the negative terminal and secure the cable away from the post. This prevents accidental shorts and protects the ECU while you handle sensors and wiring.

3. Clean the work area. Dirt can easily fall into open timing covers or oil passages. A clean garage floor and wiped-down engine bay are essential.

4. Drain the engine coolant. J-series engines have coolant passages in the intake manifold and around the timing cover. Drain the radiator and remove the lower hose to prevent spills when you remove the water pump pulley. Refill with fresh Honda Type 2 coolant after reassembly.

5. Lift the front of the vehicle. Jack the front end up, place on stands, and remove the front wheels. This gives you access to the passenger-side wheel well, which you’ll need to reach the crankshaft damper and timing cover bolts.

Step-by-Step Installation – Detailed Guide

Step 1: Remove the Engine Covers and Accessories

Start by removing the plastic engine cover (if equipped) and any intake ducting that obstructs the valve covers. Use a 10mm socket to unbolt the cover and set the fasteners aside. Next, remove the serpentine belt from the alternator and power steering pump. A belt tool or a 19mm wrench on the tensioner will release tension. Mark the belt direction before removal if you plan to reuse it (though replacement is recommended).

Step 2: Remove the Valve Covers

Unbolt the valve covers using a 10mm socket. There are approximately 10–12 bolts per bank (left and right). Notice the rubber grommets under each bolt – they compress and should be replaced. Carefully lift each valve cover straight up to avoid cracking the gasket. If the gasket is stuck, gently tap the sides with a rubber mallet. Place the covers on a clean surface, gasket side up, and remove the old gaskets, spark plug tube seals, and any RTV remnants.

Step 3: Set the Engine to Top Dead Center

Rotate the crankshaft using a 19mm socket on the crankshaft pulley bolt (turn clockwise only). Align the timing mark on the crankshaft damper with the “0” mark on the timing cover. Then verify that the camshaft sprocket marks align with the cylinder head surfaces. For the J-series, both cam sprockets have a small notch that should point to the top when at TDC. Confirm with a service manual diagram for your specific engine code.

Step 4: Remove the Timing Belt

With the engine at TDC, remove the upper timing cover (several 10mm bolts). Then unbolt the lower timing cover. You may need to remove the crankshaft pulley first – use a pulley holding tool and a breaker bar. Once the covers are off, loosen the timing belt tensioner (usually a 14mm bolt) and slide the tensioner back to release belt tension. Remove the belt from the cam sprockets and crankshaft sprocket. Pay close attention to the routing; take a photo for reference.

Critical: Do not rotate the crankshaft or camshafts separately once the belt is off. If you must rotate them, mark the cam gears and crank keyway so you can realign later.

Step 5: Remove the Old Camshafts

Each J-series cylinder head has one intake and one exhaust camshaft per bank (total of four camshafts in a V6). Begin by unbolting the cam cap bolts in a crisscross pattern (reverse of tightening order). The bolts are under the valve cover area. Use a 10mm socket – pay attention to different lengths; some caps have longer bolts. Remove the caps in sequence and set them aside in order (you can number them with a marker). Lift the camshaft out of the head. Repeat for the other cams. Be careful not to drop the cam lobes onto the journals – the surfaces are precision-ground.

Step 6: Install the Toda Racing Camshafts

Before installing the new cams, clean the bearing journals and camshaft surfaces with brake cleaner. Apply a thin coat of clean engine oil to the Toda cam lobes and bearing surfaces. Place each cam into its respective seat – note that intake and exhaust cam profiles are different; Toda marks their cams clearly. Install the cam caps in the correct order and torque them in three stages using a crisscross pattern. Factory torque spec is typically 7–9 ft-lb (84–108 in-lb) for the small bolts. Use a torque wrench accurate in inch-pounds.

Valve lash check: Toda street cams often use the stock rocker arms and adjustment screws. Verify valve clearance per Toda’s specifications (typically 0.006–0.008 in for intake, 0.008–0.010 in for exhaust on a cold engine). Adjust by loosening the lock nut and turning the adjustment screw. This step is critical – too tight can burn valves; too loose creates noise and reduced lift.

Step 7: Replace Cam Seals and Reinstall Timing Belt

Install new front and rear camshaft seals using a seal driver or a socket of appropriate size. Gently tap them in until flush. Now route the new timing belt over the crankshaft sprocket, then over the two cam sprockets, ensuring the timing marks still align. Install the tensioner and set the tension according to Honda’s procedure (rotate the crank two full turns and check alignment). Torque the tensioner bolt to 33 ft-lb.

Step 8: Reinstall Timing Covers and Valve Covers

Clean the camshaft caps and cylinder head mating surfaces. Apply a small bead of RTV at the corners of the cam cap joints (where the valve cover gasket will sit). Place the valve cover gaskets into the groove and press the covers down. Torque the valve cover bolts to 7 ft-lb in the proper sequence (start from the center and work outward). Reattach the timing covers with new sealant on the lower cover seam.

Step 9: Reassemble Accessories and Reconnect Battery

Reinstall the crankshaft pulley (torque to 180 ft-lb), serpentine belt, intake ducting, and engine cover. Reconnect the negative battery terminal. Fill the engine with fresh oil and filter. Refill coolant. Check for any tools left in the engine bay.

Post-Installation Procedure

Initial Start-Up

Start the engine and let it idle. Listen for any unusual knocking or ticking. If you hear severe tapping, shut down immediately and recheck valve lash. Normal camshaft break-in ticking should be minimal. Let the engine reach operating temperature (about 5–10 minutes). Inspect for oil leaks at the cam seals and valve covers.

Important: Do not rev the engine above 3,000 RPM during the first 20 minutes of run time. The cam lobes need a low-load break-in to mate with the rocker arms. After the initial idle, change the engine oil and filter to remove any metal particles from break-in.

Test Drive and Tuning

Take the car for a gentle drive, gradually increasing RPM through the gears. After 20–30 miles, you can begin using full throttle. However, note that Toda camshafts often require ECU tuning (reflash or standalone) to fully realize the power gains. The factory fuel and ignition maps are not optimized for the new cam profile. Consider a custom tune from a reputable shop like Hondata or KT Performance. Without a tune, you may experience a check engine light, rough idle, or suboptimal performance.

Tips for Maximum Performance

  • Pair with bolt-on modifications: A cold air intake, free-flowing exhaust headers (e.g., RV6 or J-Pipe) and a larger throttle body help the camshaft breathe. The combined setup can yield 30–40 whp gains.
  • Upgrade valve springs: For aggressive Toda cam profiles (B-spec or higher), switch to Toda valve springs or dual valve springs to prevent float at high RPM.
  • Adjustable cam gears: Using adjustable cam gears allows you to fine-tune valve overlap and timing. This is especially helpful if you have ported heads or a high-lift cam.
  • Use quality oil: Toda recommends 5W-30 or 0W-40 synthetic oil for break-in and normal use. Change the oil every 3,000 miles to keep the cam lobes happy.

Common Mistakes to Avoid

  • Reusing old timing belt components: Always replace the belt, tensioner, and water pump when you have the timing cover apart. A $200 belt set is cheap insurance.
  • Skipping valve lash adjustment: Assuming factory valve adjust is correct for aftermarket cams can lead to burnt valves or reduced power. Check and set all clearances.
  • Forgetting to mark cam cap positions: Each cap is machined to a specific journal. Mixing them up can cause binding or scoring.
  • Over-torquing aluminum bolts: J-series engine blocks and heads are aluminum. Use an inch-pounds torque wrench for small fasteners to avoid stripping threads.

Conclusion

Installing a Toda Racing camshaft in your J-series engine is a satisfying project that pays off with a noticeable increase in horsepower and a more aggressive exhaust note. By following this step-by-step guide, using quality parts, and taking the time to set valve lash correctly, you can achieve a reliable performance gain that transforms your daily driver or weekend track car. For further guidance, consult Toda Racing’s official installation manual (available at TodaRacing.com) and seek community support on forums like AcuraZine or Honda-Tech. Remember – a proper tune unlocks the cam’s full potential, so budget for that step before hitting the dyno.