Honda J35s1 Engine Specs And Performance

If you’re looking for the details on a powerful and reliable V6, you’ve come to the right place. This article covers the essential Honda J35S1 engine specs and performance in a clear, detailed format. We’ll break down everything from its technical design to its real-world power, giving you the complete picture of this engineering workhorse.

The J35S1 is a specific variant of Honda’s renowned J-Series V6 engine family. It’s known for its balance of power, smoothness, and durability. Primarily found in the 2002-2004 Honda Odyssey EX-L and Touring models, this engine was the top-tier powerplant for the minivan, offering more capability than the standard option.

It represents a key step in the evolution of Honda’s V6 technology, incorporating features like Variable Cylinder Management (VCM) for the first time in the Odyssey. Understanding its specs helps explain why these vehicles remain popular with families and enthusiasts alike.

Core Technical Specifications

Let’s start with the fundamental numbers that define the J35S1. These are the baseline figures every owner or prospective buyer should know.

Engine Code: J35S1
Configuration: 60-degree V6, SOHC (Single Overhead Cam)
Displacement: 3.5 liters (3471 cc)
Bore x Stroke: 89 mm x 93 mm
Compression Ratio: 10.0:1
Valvetrain: 4 valves per cylinder (24 total), VTEC (Variable Valve Timing and Lift Electronic Control) on the intake side
Fuel System: Multi-Point Fuel Injection (PGM-FI)
Recommended Fuel: 87 Octane (Regular Unleaded)
Engine Block Material: Aluminum alloy with cast-in iron cylinder liners
Cylinder Head Material: Aluminum alloy

Key Design Features

Honda packed several advanced technologies into the J35S1 to optimize both power and efficiency. These features set it apart from earlier, simpler V6 designs.

VTEC System: This system varies the timing and lift of the intake valves. It improves low-end torque and high-end horsepower, giving you a broader, more usable powerband.
Variable Cylinder Management (VCM): This was Honda’s first-generation cylinder deactivation system. Under light load (like highway cruising), it could deactivate three cylinders (the rear bank), turning the V6 into a straight-3 to save fuel.
Drive-by-Wire Throttle: Replacing a traditional cable, an electronic signal from the gas pedal controls the throttle body. This allows for more precise integration with the VCM and transmission systems.
Balancer Shafts: Located in the oil pan, these counter-rotating shafts cancel out inherent V6 vibrations, contributing to the engine’s famously smooth operation.

Detailed Performance Output

Now for the numbers that matter most when you press the accelerator. The J35S1 was tuned for strong, accessible power suitable for a heavy vehicle.

Horsepower: 240 hp @ 5500 rpm
Torque: 242 lb-ft @ 4500 rpm
Redline: 6200 rpm (Fuel cut-off)

This power output was significant for its time, giving the hefty Odyssey confident passing power and the ability to handle full loads without strain. The torque peak at a moderate 4500 rpm means you feel a strong pull in everyday driving situations, not just at high engine speeds.

Applications: What Vehicles Used the J35S1?

The engine had a specific, targeted application. It wasn’t spread across the entire Honda lineup.

2002-2004 Honda Odyssey (EX-L and Touring trims): This is the primary and most common application. The lower trims (LX and EX) used the non-VCM J35A4 engine with less power.

It’s crucial to check your vehicle’s VIN or engine bay plaque to confirm you have the J35S1, as the Odyssey models from these years could have one of two different 3.5L engines.

Transmission and Drivetrain Pairing

The J35S1 didn’t work alone. It was paired with a specific transmission designed to handle its torque and integrate with the VCM system.

Transmission: 5-speed automatic (Model: B7XA)
Drivetrain: Front-wheel drive
Final Drive Ratio: 4.375:1

This five-speed automatic was a robust unit, though it’s known for requiring diligent maintenance, especially regular fluid changes, to ensure long-term reliability. The gear ratios were well-matched to the engine’s power curve.

Real-World Fuel Economy

Thanks to the VCM system, the J35S1 aimed to balance V8-like power with better fuel efficiency. Official EPA estimates for the 2004 Odyssey are as follows:

City MPG: 17
Highway MPG: 24

In real-world driving, owners often report highway mileage in the low-to-mid 20s, with city driving dipping into the mid-teens, especially with a heavy foot or lots of stop-and-go traffic. The effectiveness of VCM is most noticeable on steady highway journeys.

Maintenance Schedule and Key Service Points

To keep a J35S1 running smoothly for 200,000+ miles, adhering to Honda’s maintenance schedule is key. Here are the critical items.

Oil Changes: Every 5,000-7,500 miles with 5W-20 weight oil. Frequent changes are vital due to VCM operation, which can lead to fuel dilution in the oil.
Timing Belt: Replace every 105,000 miles or 7 years. This is an interference engine, so a failed belt causes catastrophic damage.
Spark Plugs: Replace with Iridium plugs every 105,000 miles, often done during the timing belt service.
Automatic Transmission Fluid (ATF): Drain and fill every 30,000-60,000 miles. This is perhaps the most critical service for long-term health of the paired transmission.
Coolant: Replace every 10 years or 120,000 miles with Honda Type 2 coolant.

Common Issues and Reliability

No engine is perfect, and the J35S1 has a few known areas to watch. Awareness helps you prevent minor problems from becoming major repairs.

VCM-Related Issues: Early VCM systems could cause excessive oil consumption, fouled spark plugs (especially in deactivated cylinders), and premature ring wear. Using a “VCM tuner” to disable the system is a common modification by owners.
Automatic Transmission Concerns: The B7XA 5-speed can suffer from rough shifting, torque converter shudder, or failure if the fluid is not changed regularly. The 2002 model year had the most reported issues.
Power Steering Pump Leaks: The high-pressure hose and pump seals can develop leaks over time, dripping fluid onto the alternator and potentially causing it to fail.
Exhaust Manifold Cracks: Some engines develop cracks in the cast-iron exhaust manifolds, leading to an exhaust leak noise, particulary on cold starts.

Despite these points, with proactive maintenance, the J35S1 is generally considered a very reliable and long-lasting powerplant. Many examples are still on the road today with high mileage.

Performance Modifications and Tuning Potential

While not a typical tuner engine like a K-Series, there are ways to extract a bit more performance from the J35S1. The gains are modest, as the engine is already well-optimized from the factory.

Cold Air Intake (CAI): Can improve throttle response and add a more aggressive intake sound. Horsepower gains are minimal.
Exhaust System: A cat-back exhaust system can reduce backpressure and free up a few horsepower, with a deeper tone.
VCM Disabler: While not a power mod, disabling VCM can lead to more consistent engine operation, reduced oil consumption, and potentially smoother performance for some drivers.
Professional Tune: A custom ECU reflash can optimize ignition timing and fuel maps, especially if paired with intake/exhaust mods. This is the most effective way to gain power, but options are limited for this older ECU.

Remember, this engine is in a heavy front-wheel-drive vehicle. Major power adders like forced induction are complex, expensive, and can overwhelm the transmission.

Comparing the J35S1 to Other J35 Engines

How does it stack up against its siblings? Here’s a quick comparison.

vs. J35A4 (2002-2004 Odyssey LX/EX): The A4 lacks VCM and VTEC, producing only 215 hp and 229 lb-ft of torque. It’s simpler but less powerful and less efficient on the highway.
vs. J35A8 (Pilot, MDX): The A8, used in SUVs, is more similar but tuned for lower-end torque (244 lb-ft @ 3500 rpm) and does not have VCM. It uses a different intake manifold and tuning.
vs. Later J35Z (2005+ Odyssey): Later engines increased displacement to 3.7L, adopted a drive-by-wire throttle, and used more advanced VCM systems, producing more power and torque.

FAQ Section

What is the difference between the J35A4 and J35S1?

The main differences are VTEC and VCM. The J35S1 has VTEC on the intake valves and the Variable Cylinder Management system, giving it 25 more horsepower and better highway fuel economy compared to the base J35A4.

Is the Honda J35S1 engine reliable?

Yes, it is generally very reliable when properly maintained. Key concerns are the timing belt service interval and potential for oil consumption or transmission issues if fluid changes are neglected. Addressing these points leads to a long engine life.

What kind of gas mileage does the J35S1 get?

Expect around 17 mpg in city driving and 23-25 mpg on the highway in a Honda Odyssey. Real-world results depend heavily on driving style, load, and maintenance condition.

Can you turn off VCM on the J35S1?

Yes, many owners install a simple aftermarket device called a VCM tuner or blocker. It interrupts the signal that activates the cylinder deactivation system, which can reduce oil consumption and smooth out engine operation for some.

How much horsepower does the J35S1 have?

The factory rating is 240 horsepower at 5500 RPM. This was a strong figure for a minivan engine in the early 2000s.

When should the timing belt be changed on this engine?

Honda recommends replacement at 105,000 miles or 7 years, whichever comes first. Because this is an interference engine, failing to change it can result in bent valves and major engine damage if it breaks.

What oil is best for the J35S1?

Use a high-quality 5W-20 weight motor oil that meets API specifications. Given the potential for fuel dilution from VCM, sticking to a 5,000-mile change interval is a wise precaution for maximum engine longevity.