JDM H23A Blue Top 2.3L DOHC VTEC Engine

If you want more torque from your H-series Honda, the JDM H23A “Blue Top” deserves a close look. Honda built this 2.3L DOHC VTEC engine for the Japanese-market 1998–2002 Accord SiR wagon. In other words, it pairs a longer-stroke 2.3L bottom end with an H22-style VTEC head. As a result, it makes strong mid-range torque while it still loves high RPM. Today, Prelude owners especially seek it out as an upgrade over the H22A4.

H23A Blue Top at a Glance

First, the basics: the H23A displaces 2,258 cc with an 87 mm bore and a 95 mm stroke. In stock form, Honda rated it at 200 PS (197 hp) at 6,800 rpm and 163 lb-ft (221 Nm) at 5,300 rpm. Also, it uses a 65 mm throttle body, which is larger than the one on a typical H22. This engine, serial H23A-2024981, shows about [XX,XXX] miles. In addition, it tested at [XXX / XXX / XXX / XXX] PSI on our compression gauge. Finally, it comes with a 90-day warranty.

H23A vs H22A4: Why Prelude Owners Upgrade

Compared with the USDM H22A4, the H23A adds roughly 100 cc of displacement. Consequently, the car pulls harder in the mid-range, where you spend most of your street driving. Meanwhile, the VTEC head still delivers the high-RPM character that Prelude owners love. Better yet, many H22A4 head parts interchange with the Blue Top, so service and future upgrades stay simple.

Fitment

Most buyers install the H23A in a 1997–2001 Honda Prelude as a replacement for the H22A4. In addition, builders use it in 1992–1996 Preludes and in H-series-swapped Accords. However, every swap depends on your chassis, transmission and wiring. For that reason, confirm the details with us before you order.

Keep in mind that the U.S. 1998–2002 Accord came with an F23A, not an H-series engine. Therefore, an H23A in that car becomes a custom swap that needs aftermarket mounts, axles and wiring.

Swap Notes

1. First, compare the driver-side engine bracket. If it differs, use a 1992+ Prelude H-series bracket.
2. Next, check oil pan clearance, because the Blue Top can use a deeper pan than a typical H22.
3. Then, plan your intake. In most cases, the factory H23A intake manifold goes on more easily than an adapted H22 manifold.
4. After that, match the sensors and connectors to your Prelude’s engine harness.
5. Finally, confirm your ECU choice and get a tune before the first hard drive.

Above all, keep your original engine until the swap is complete. That way, your installer can compare parts side by side.

What’s Included

• H23A long block (head, block and internals)
• [Attached components as shown in photos – list or confirm]

We include only the items listed above or shown in the photos. So, if you need a specific part, call us before you order.

Before You Install

The H23A uses a timing belt and a balance shaft belt. Therefore, replace both belts, the tensioner and the water pump while the engine sits outside the car. At the same time, replace the cam and crank seals, the valve cover gasket and the spark plugs. Also, check valve lash, since H-series engines use adjustable valves.

Before the first start, prime the oil system with fresh oil and a new filter. Then, fill and fully bleed the cooling system. During the first heat cycles, watch oil pressure, coolant temperature and leaks. Finally, confirm that VTEC engages properly before you drive hard.

Shipping, Pickup & Installation

We ship engines by freight across the continental U.S., usually within 1–2 business days. After the engine leaves our shop, delivery typically takes 2–7 business days, and the driver needs your signature. Alternatively, local customers can pick up at our Henrico, VA shop near Richmond. In addition, our technicians handle complete H-series swaps in-house. To get started, schedule an appointment or call 866-683-3747.

Frequently Asked Questions

What is an H23A Blue Top?

It’s the 2.3L DOHC VTEC engine from the JDM 1998–2002 Honda Accord SiR wagon. In fact, it gets its nickname from its blue valve cover.

Will the H23A fit my 1997–2001 Prelude?

Yes, it’s one of the most popular Prelude upgrades. However, check the driver-side bracket, oil pan clearance and harness connectors before installation.

Is the H23A better than the H22A4?

For street driving, many owners prefer it. Because it has more displacement, it makes more mid-range torque, while the VTEC head keeps the high-RPM pull.

Will it fit my U.S. 1998–2002 Accord?

Not directly. Since that car came with an F23A, the swap needs aftermarket mounts, axles and wiring.

Does the H23A have a timing belt?

Yes. Therefore, replace the timing belt, balance shaft belt, tensioner and water pump before installation.

What warranty is included?

Every engine comes with a 90-day warranty. For full terms, see our warranty page.

Can I reserve this engine?

Yes. First, pay a 5% deposit at checkout to hold the engine. Then, pay the balance within two weeks.

Related: All JDM H22A & H23A engines · JDM transmissions · JDM ECUs · Financing