Introduction: Unlocking the True Potential of Your B16

The Honda B16 engine is already a legend among enthusiasts, known for its high-revving character and impressive power output. Yet even the best factory designs leave room for improvement. Swapping in a Toda Racing camshaft is one of the most effective single modifications you can make to your B16. Toda Racing has been a premier Japanese performance parts manufacturer for decades, and their camshafts are engineered with precision profiles that increase valve lift and duration, translating directly into measurable gains in horsepower and torque across the power band. This comprehensive guide will walk you through every step of installing a Toda Racing B16 camshaft, from the tools you need to the final tuning steps. Whether you are a seasoned DIY mechanic or a motivated beginner, following this process carefully will help you avoid costly mistakes and get the most out of your new cam.

Tools and Materials: Prepare for Precision Work

Before you touch a wrench, assemble all necessary tools and replacement parts. Using the correct tools not only makes the job easier but also prevents damage to the delicate engine components. Many of these items are available at any auto parts store, or you can order specific high-quality tools from suppliers like Toda Racing’s official website or a trusted tool brand.

Essential Tools

  • Socket set: A metric set ranging from 8mm to 19mm, including deep sockets for timing cover bolts.
  • Torque wrench: Critical for tightening cam cap bolts, timing belt tensioner, and other fasteners to manufacturer specs. A 3/8-inch drive torque wrench (5-75 ft-lb range) is ideal.
  • Screwdrivers: Flathead and Phillips for removing hose clamps and small brackets.
  • Camshaft installation tool: A dedicated tool helps align the camshaft and prevents it from rotating during bolt tightening. Many generic cam tools work with Honda B-series.
  • Timing belt locking tool or pin: To secure the cam gears while the belt is off.
  • Breaker bar: For stubborn bolts, especially the crankshaft pulley bolt if you need to remove it.
  • Plastic or brass drift: To tap the camshaft into place without damaging the lobes.

Replacement Parts and Consumables

  • New camshaft seals: Always replace the front and rear cam seals. Toda Racing recommends OEM Honda seals or high-quality aftermarket units.
  • Engine oil: 5W-30 or 10W-40 synthetic race oil (depending on climate) for the break-in period. You’ll need about 4-5 quarts.
  • Gasket maker (RTV silicone): For the valve cover and timing cover gasket surfaces if using liquid gasket instead of pre-formed gaskets.
  • Valve cover gasket set: It’s best to replace the valve cover gasket and spark plug tube seals during reassembly.
  • Coolant: If you drain the radiator (recommended), refill with fresh 50/50 mix.
  • Threadlocker (Loctite 242): For critical bolts like cam cap bolts to prevent loosening from vibration.

Safety Gear

  • Safety goggles: Protect your eyes from oil splashes and debris.
  • Gloves: Nitrile or latex mechanics gloves keep oil off your hands and improve grip.
  • Jack stands: If you need to access the under-engine area for the crankshaft pulley.

Preparation: Set the Stage for Success

Proper preparation reduces the risk of errors and ensures you have clear access to the camshaft area. Park the car on a level surface, engage the parking brake, and disconnect the battery (negative terminal first). Drain the engine oil by removing the drain plug and letting the oil flow into a suitable container. While not strictly necessary, draining the oil prevents spills when you remove the camshaft and reduces mess. It’s also a good time to drain the coolant from the radiator by opening the petcock at the bottom—this allows you to remove the upper radiator hose later if needed.

Next, remove the engine cover (if equipped) and intake manifold. For a 1992-2000 Civic Si or Integra LS/GSR with a B16, the intake manifold houses the throttle body and fuel injectors. Label and unplug all electrical connectors, vacuum lines, and fuel lines (relieve fuel pressure first by loosening the banjo bolt at the fuel rail). Removing the intake manifold opens up a lot of space on the left side of the engine, making cam removal much easier. If you’re not comfortable removing the intake manifold, you can work around it, but clearance will be tight.

Removing the Old Camshaft

With the engine exposed, you can now access the timing components and the camshaft itself. This section is critical—take your time and double-check every step.

Step 1: Remove Timing Belt Cover and Tension

Start by removing the upper and lower timing belt covers. The upper cover (black plastic) is held by several 10mm bolts; the lower cover may require removing the crankshaft pulley (17mm or 19mm bolt). Use a breaker bar and a crank pulley holder tool to prevent the engine from rotating. Once the covers are off, verify that the timing marks are aligned: rotate the crankshaft with a large socket until the TDC (top dead center) mark on the crankshaft pulley aligns with the 0° mark on the timing cover, and the cam sprocket marks point straight up. This ensures the engine is in the correct position for cam removal.

Loosen the timing belt tensioner by rotating it with a 14mm socket (or hex key, depending on version). Slide the belt off the cam sprocket. Do not force the belt—if it’s tight, release more tension. Mark the belt’s rotation direction with a white marker so you can reinstall it the same way.

Step 2: Remove Camshaft Cap Bolts and Camshaft

Using a 10mm socket, loosen the camshaft cap bolts in a crisscross pattern, starting from the outer ends and working inward. This prevents warping the caps. Once all bolts are removed, lift the cam caps off and set them aside in order—they are specific to each position. You can place them on a clean work surface with tape labeling them 1 through 5 (front to rear). Carefully lift the old camshaft out of the head. It should slide out easily. If it’s stuck, because of carbon buildup or seized journal, do not hammer it. Spray penetrating oil around the journals and gently rock it side to side. Once removed, inspect the camshaft lobes and journals for scoring—this can indicate oil starvation or previous wear.

Installing the Toda Racing Camshaft

Now the exciting part: fitting your new Toda Racing cam. These camshafts are precision-ground from chilled cast iron or billet steel, depending on the model. Handle them with care—any nick on the lobes can ruin the cam.

Step 1: Lubricate and Position

Apply a generous amount of engine assembly lube or fresh engine oil to the cam journals and lobes. Toda Racing recommends using a high-zinc break-in oil such as Lucas Hot Rod Oil or a dedicated race oil. Slide the new camshaft into the cylinder head from the front (timing belt side). Push it in slowly, rotating it slightly to help the journals align. Do not force it.

Step 2: Align Timing Marks and Secure

Before installing the cam caps, align the camshaft sprocket timing mark (usually a single dot or notch) with the TDC mark on the valve cover or a straight edge across the head surface. For the B16, the cam gear should have the “UP” mark facing upward. Install the cam caps in their original order (if reusing them from the old cam) or use the new caps that come with the Toda cam (if included). Tighten the cap bolts in a crisscross pattern to the factory spec—typically 8.7 ft-lb (11.8 Nm) for the smaller bolts and 16 ft-lb (22 Nm) for the larger ones. Use a torque wrench; overtightening can distort the caps and seize the cam.

Step 3: Install New Seals and Cam Gear

Press new cam seals into the front and rear of the cam housing. Use a seal driver or a socket of the same diameter to seat them flush. Do not damage the sealing lip. Reinstall the cam sprocket and tighten the bolt to 49 ft-lb (66 Nm) while holding the cam with a cam locking tool. Now reinstall the timing belt, ensuring the crankshaft is still at TDC. Tension the belt according to the manufacturer’s procedure (rotate the tensioner to achieve the specified deflection, usually about 0.5-0.6 inches of belt movement at the longest span). Rotate the engine by hand two full revolutions to verify the timing marks still align. If they don’t, repeat the alignment.

Reassembling the Engine

With the new camshaft installed and timed, it’s time to put everything back together. This is also a good opportunity to replace the water pump and timing belt tensioner if they show signs of wear, as a failing tensioner can quickly ruin your new cam.

  • Install valve cover: Apply a thin bead of RTV silicone on the corners of the cam cap journals and on the front and rear cam seal areas. Place the new valve cover gasket in the cover, then fit the cover on the head. Tighten the 10mm bolts to 7 ft-lb (about 9 Nm) in a crisscross pattern.
  • Reinstall intake manifold: Clean the mating surfaces, use a new gasket, and torque the manifold bolts to 16 ft-lb (22 Nm). Reconnect all vacuum lines, fuel lines (replace crush washers), and electrical connectors.
  • Refill fluids: Add 4.5 quarts of fresh engine oil through the valve cover cap. Fill the radiator with coolant.
  • Battery: Reconnect the negative battery cable.

Tuning and ECU Considerations

Installing a Toda Racing camshaft changes the engine’s air flow dynamics significantly. The stock ECU cannot optimize ignition timing and fuel delivery for the new cam profile, especially at idle and high RPM. To get the full power increase—typically 15–25 extra horsepower depending on the cam spec—you must install a programmable ECU (such as Hondata S300, AEM EMS, or a MoTeC) and have the car professionally tuned on a dynamometer. Many owners also upgrade the valve springs and retainers to prevent valve float at high RPM. Toda Racing offers matching spring sets for their cam profiles. If you skip the tune, the engine will run poorly, might backfire, and you risk damaging the engine.

For a budget-friendly option, some tuners can provide a base map for your specific cam and injectors that you can flash using a chip burner. However, a proper dyno tune is always recommended. Visit Hondata’s website for more information on compatible ECUs and tuning services.

Final Checks and Testing

Before starting the engine, perform a thorough inspection:

  • Double-check all bolts are torqued to spec, especially cam cap bolts, cam sprocket bolt, and timing cover bolts.
  • Rotate the engine by hand (using the crankshaft pulley bolt) at least two full revolutions to ensure no internal interference. Listen for any scraping or clicking that could indicate a valve contacting the piston (rare with mild cams, but possible with aggressive profiles).
  • Check for oil leaks at the cam seals and valve cover. If dry, proceed.

Start-Up and Break-In Procedure

Start the engine. It may idle higher than normal initially because the ECU is learning the new cam timing. Let it idle for 15-20 minutes while monitoring the oil pressure gauge (if equipped). Do not rev the engine high for the first 500 miles—keep it under 4000 RPM and vary the load to aid ring seating. After the first oil change at 500 miles, you can drive it more aggressively and schedule a dyno tune.

If you hear tapping sounds, it could be due to insufficient lash clearance. Toda Racing cams often require adjusting valve lash (mechanical tappet clearance) to a specific value—typically 0.006-0.008 inches (0.15-0.20 mm) for intake and 0.008-0.010 inches (0.20-0.25 mm) for exhaust. Use a feeler gauge to check and adjust the tappets. This step is often overlooked by first-time installers but is essential for smooth operation.

Expected Performance Gains

With a properly installed and tuned Toda Racing B16 camshaft, you can expect a power increase of 15-25 horsepower at the wheels. The engine will also gain torque in the mid-range and pull harder to redline. The exact gains depend on the cam profile (e.g., Toda Spec B, Spec C, or race-only profiles) and your supporting modifications (header, intake, fuel system). Combined with a lightened flywheel and a free-flowing exhaust, a B16 with a Toda cam can easily produce 170-190 whp—a solid improvement over the stock 160 hp at the crank.

Whether you are building a weekend track car or spirited daily driver, the Toda Racing camshaft is a proven upgrade that transforms the B16’s character. Take your time with the installation, invest in a quality tune, and enjoy the newfound power.

For more detailed technical specifications and dyno charts, visit Toda Racing’s product page: Toda Racing Camshafts. Also, check out the B-series tuning guide at B-Series.com for community tips on installation and tuning.