Honda B18 Engine Guide

Over the course of the 1.8L Honda B18’s 11-year build cycle between 1990 and 2001, it was released in 16 different variants ranging from the B18 to the Type R B18C7. The Honda B18 has twice the number of variants as the earlier B16 and 2.0L B20 engines. That also makes the B18 one of the most common and most sought-after engines in the B-Series platform. The United States only received 6 of the 16 B18 variants including the B18A1, B18A2, B18B1, B18B2, B18C1, and B18C5. 

In this guide, we’ll cover the Honda B16, including its specifications, performance capabilities, common modifications, and reliability.

Engine Specifications

Engine	Honda B18
Configuration	Inline-4 Cylinder
Displacement	1.8L (1,797 – 1,834 cc)
Aspiration	Naturally Aspirated
Valvetrain	DOHC (Some With VTEC)
Block/Head	Aluminum/Aluminum
Bore x Stroke	81 mm × 89 mm (3.19 in × 3.50 in)
Compression Ratio	9.2:1 – 11.1:1
Weight	Long Block ≈ 395 lbs
Horsepower	130-197 bhp @ 6,000-8,000 RPM
Torque (lb-ft)	121-133  lb-ft @ 5,000 – 7,500 RPM

The Honda B18 shares many of the same attributes as the B16 engine that preceded it. The B18 features an aluminum block and aluminum head, making it a light engine at just 395 lbs. It is also an exceptionally strong engine featuring cylinder sleeves from the factory and bulletproof internals capable of withstanding more than 100 horsepower than its factory output.

The Honda B18 is the middle child in the B-Series lineup. With 1.8L of displacement, it outsizes the Honda B16 engine with a displacement of 1.6L but it has a smaller displacement than the larger Honda B20 engine with, you guessed it, 2.0L of displacement. Despite the small displacement, the B18 engine is able to produce a respectable amount of power due to multiple innovations by Honda. Like the Honda B16, the B18 continued the dual overhead cam arrangement. The B-Series was sold as the higher performance version of the Honda D-Series which were all single overhead cam engines. 

One of the B18’s primary selling points is its strong torque figures. Even the least powerful B18A1 produced 121 lb-ft of torque. The most powerful US B18C5 produced 130 lb-ft at 7,500 rpm, making it a good engine for racing. 

Engine Applications

First Generation B18A

• 1986–1989 Accord Aerodeck LXR-S/LX-S (Japan)
• 1986–1989 Accord EXL-S/EX-S (Japan)
• 1986–1989 Vigor MXL-S (Japan)

B18A1

• 1990–1991 Acura Integra USDM “RS/LS/LS Special Edition/GS” (DA9 Liftback/Hatchback, DB1 Sedan)
• 1992-1993 Acura Integra USDM “GS/LS/LS Special Edition/RS” (DA9 Liftback/Hatchback, DB1 Sedan)

B18A2

• 1990-1993 Honda Integra LS DB1 Sedan

B18B1

• 94-01 Integra RS/LS/SE/GS – DB7/DC4/DC3
• 1994–2000 Honda Integra “RS/LS/GS/SE/(GSI Australia)” (DC4/DB7)
• 1992–1996 JDM Honda Domani (MA5)
• 1993–1994 JDM Honda Integra (DB7)
• 1996–1999 JDM Honda Orthia (EL1)

B18B2

• 94-01 Integra RS/LS/SE/GS – DB7/DC4/DC3
• 1994–2001 Honda Integra “RS/LS/GS/SE/(GSI Australia)” (DC4/DB7)

B18B3

• 1992–1995 Honda Civic – Middle East & South Africa Ballade (SR4)

B18B4

• 1996–2000 Honda Civic – Middle East & South Africa Ballade (SO4)

JDM B18C Type R

• 95-00 Honda Integra JDM Type R (DC2 & DB8)

JDM B18C

• 95-98 Honda Integra JDM SiR/SiR II (DB8, DC2)
• 98-99 Honda Integra JDM SiR-G (DB8, DC2)
• 2000 Vemac RD180

B18C1

• 1994–2001 Acura Integra USDM GS-R (DC2 & DB8)

B18C2

• 1994-2001 Honda Integra AUDM/NZDM VTi-R

B18C3

• Honda Integra Asian market

B18C4

• 1996–2000 UK Civic VTi 5-door Hatch (MB6)
• 1996–2000 UK Civic 1.8i VTi-S (Limited Edition) 5-door Hatch (MB6)
• 1996–2001 UK Civic Aerodeck 1.8i VTi 5-door Wagon (MC2)
• 1998–1999 EU Civic Aerodeck 1.8i VTi 5-door Wagon (MC2)
• 1998–1999 EU Civic 1.8i VTi 5-door Hatch (MB6)

B18C5

• 1997-1998,1999 CDM, 2000-2001 Acura Integra USDM/CDM Type R

B18C6 (Type R)

• 1998–2001 Honda Integra UKDM/EUDM Type R

B18C7 (Type R)

• 1999-2001 Honda Integra AUDM/NZDM Type R

Stock Engine Performance

When it comes to the Honda B18’s factory performance, it is hard to distill all of the variants into a single description. Due to the fact that there are 16 different variants to take into account, with some having dramatically different compression, peak torque and horsepower figures, and a lack of VTEC, B18 variants can act very differently. For example, the B18A2 found in the USDM 1990-1993 Honda Integra LS has significantly different characteristics than the B18C5 due to the A2’s lack of VTEC and its lower compression ratio. 

While VTEC is often seen as a requirement for a low-displacement Honda 4-cylinder in the JDM community, non-VTEC variants of the Honda B18 are still wildly popular. The Honda B18A1 is an extremely popular engine due to the fact that it is one of the cheapest B18 variants that still provides a respectable 130 horsepower. B18B engines from 1994-2001 Integras are also very popular in the Honda community. The B18B provides slightly more power than the B18A2 at 140 horsepower. While both the B18A2 and B18B lack VTEC, a VTEC head can be easily swapped onto the bottom end of both engines. This is often called an LSVTEC amongst Honda enthusiasts.

As you might have guessed the VTEC-equipped B18C is undoubtedly the most sought-after B18 engine variant in the U.S. Not only does the B18C5 have the advantage of VTEC variable valve timing, but it is also the most powerful B18 engine variant that was offered stateside. For that reason, and also because the B18C5 was only available in the desirable Acura Integra Type R, it is also the most expensive B18 variant to buy. 

Regardless of the variant, the Honda B18 in factory form is a capable engine with huge tuning potential and respectable out-of-the-box performance.

Engine Upgrades

All of the engines in the Honda B-series are known for their unparalleled reliability. In fact, if you are shooting for a “mild” horsepower figure from your B18 (200-250whp), most B-series enthusiasts will tell you that you won’t have to crack open the engine at all.  

While it is fun to consider building up a big-power turbo Honda B18 engine, it is important to first consider what the end goal of your build is. Are you shooting for a daily driven B18 Integra with a bit of extra oomph? A B18-powered drag car? Ultimately, the end goal for your B18 build will dictate the modifications that you’ll need to do. The options for a modified B18 are truly endless with the only limitation being cost. With that being said, 200-250 horsepower is a very achievable goal that won’t break the bank.

The most common high-horsepower modification for the B18 4-cylinder is a turbocharger kit. In stock form, the B18 is the perfect candidate for forced induction. With that being said, higher boost loads will require internal upgrades. Since the B18 has a comparably low compression ratio, it requires little modification to make reliable boost. In general, most people consider the B18’s stock internal hardware pretty solid. While the Honda B18’s internal components are strong, figures beyond 300whp will require some internal work.

Cams

Upgraded cams are one of the most common modifications done to Honda B-Series engines as a whole, B18s included. With that being said, there are quite a few considerations that you’ll need to take into account before purchasing upgraded B18 cams. Obviously, VTEC-equipped B18 variants like the B18C1 and B18C5 will require different cam profiles than non-VTEC B18 variants. Additionally, you’ll have to consider what type of Honda B18 build you are going for. High-horsepower B18 Hondas meant for drag racing will obviously need far more aggressive cams than a mild B18 street build. Luckily, there are tons of B18 cam options out there regardless of your application. 

When it comes to upgraded Honda B18 cams, you’ll have to consider where in the rev range you want the largest increase in performance. Some Honda owners like to select a B-Series cam that will push peak power output toward the top of the rev range, as that is the best setup for track driving. Alternatively, there are plenty of mild-grind B18 cam options that will increase performance throughout the entire rev range. 

B18 cam performance is dependent on a bunch of other factors as well. For instance, the intake manifold and exhaust that you choose to run on your B18 can have a significant impact on where in the rev range peak power is produced. It is also commonly said that mild grind cams don’t tend to work as well in B18 variants with lower compression like the B18A and B18C1. Higher compression pistons or a different head gasket are often recommended for mild grind cams. You’ll also need to upgrade your valve springs and spring retainers.

Depending on the cam grind and tune, it is possible to get anywhere from 15-100 horsepower out of a set of B18 cams. 

LSVTEC Head Swap

Due to the fact that the majority of the Honda B18 engines we received in the US lacked VTEC, one of the most common modifications for those that have non-VTEC B18 variants is to swap a VTEC head onto their non-VTEC bottom end. This applies specifically to the B18A1, B18A2, B18B1, and B18B2 variants. The performance increase from doing this modification to a non-VTEC B18 is significant. Mild LSVTEC builds produce around 200 horsepower and more aggressive builds make close to 300whp. 

The DOHC VTEC head can be taken from a number of different Honda engines. The most common heads include B16, Type R, or GSR heads. At the end of the day, the head that you choose to use boils down to personal preference. Some people prefer the smaller combustion chamber of the P72 GSR head. Others like the B16 head as it allows for the higher-flowing ITR manifold to bolt on directly. Either way, any DOHC VTEC cylinder head will work. 

In addition to the non-VTEC B18 block and DOHC VTEC head, you’ll also need some other parts. One of the most important components is an LS VTEC oil supply kit, like the Golden Eagle B-Series VTEC Conversion Kit, which will allow the new DOHC VTEC head to be supplied with oil without the need for any independent machining. You’ll also need rod bolts, head studs, a new oil pump, GSR/ITR timing belt, and a modified ECU. 

In general, the LS VTEC is the most noteworthy and rewarding modification that you can do to a non-VTEC B18 engine. It is almost a necessity to make big naturally aspirated power from a B18 engine that is lacking VTEC. 

If you are looking for information about this swap, check out this article by AxleAddict.com

Turbo Upgrade

Forced induction is a very popular modification on the Honda B-series and the B18 in particular. A lot of Honda owners opt to turbocharge their cars with a prepackaged turbo kit that comes with all of the necessary components. As we stated earlier, the B18 is an extremely resilient engine. The B18 can handle over 100+ more horsepower than stock with no significant internal upgrades.

Despite its overall strength, many experienced B18 turbo enthusiasts still advocate for reinforcing the B18’s bottom end, upgrading the fuel system, replacing the timing chain assembly, refreshing the valve springs, and upgrading the factory head gasket. These precautions further bolster a 250-300 horsepower turbocharged B18 against high internal forces introduced by forced induction.

Once you reach the 350-400 horsepower mark, more extensive modifications are required. At this point, it is a good idea to have a machine shop resurface the cylinder head and the block. This is also the point where you’ll need to upgrade to forged internals. An upgraded crankshaft, forged pistons, rods, and upgraded rod & main bearings should all be considered at that point.

The 400-horsepower threshold is also when you should consider sleeving your B18’s block. This will reduce the amount of internal wear that your B18 experiences and act as an additional level of reinforcement. It also allows for larger bore diameters.

An upgraded fueling system is also necessary for high-horsepower B18 builds. The primary components that should be upgraded include the factory fuel pump, injectors, fuel lines, and fuel rail. For 400+ horsepower, you’ll need a AEM 340lph fuel pump (minimum), 1000cc injectors, -8AN supply fuel lines, -6AN return fuel lines, and a high-flow fuel rail. 

Engine Problems

As many people are probably aware, Honda 4-cylinder engines are some of the most reliable powerplants out there if maintained properly. It is important to note that modified B18 engines might not share the same longevity. Generally speaking, reliability is inversely proportional to horsepower with the B18 and most other engines for that matter. With that being said, moderately upgraded engines can also be extremely reliable depending on the engine tune, quality of parts, and other related factors.

So, when it comes to common B18 engine problems, the list is relatively short. Most of the issues associated with engine are due to the fact that the older variants are over 30 years old at this point. With any engine of that age, rubber hoses, seals, and other wear-and-tear items tend to degrade, causing associated problems. One of the most reported issues is premature water pump and thermostat failure. While this is somewhat of a spontaneous issue and can’t be pinned down to a particular mileage, it is always a good idea to be mindful of your temp gauge to ensure that it isn’t overheating. A water pump replacement on a Honda B18 can be somewhat involved, as you’ll likely have to replace the timing belt, tensioner, and bearings at the same time. 

Once Honda B18 engines approach the 200,000-mile mark, it is common for them to start leaking and burning oil. Over time, the rubber camshaft seals and other similar seals will degrade and begin to leak oil. Oil can also begin to leak into the combustion chamber through the piston rings and valves, causing it to burn oil. Ultimately, this is an issue for almost every high-mileage engine and is not specific to the B18. 

Honda B16 Engine Legacy

The Honda B-Series truly redefined the high-horsepower, low-displacement 4-series, and the 1.8L played a significant role in the B-Series’ legacy. Not only is the B18 extremely efficient in factory form, but it is also a resilient engine that takes modifications well and holds up against added power. For that reason, it is one of the most popular 4-cylinder engines among tuners and enthusiasts.

While the United States missed out on many variants, the 6 that we did get are all capable engines. Despite the fact that the majority of U.S. B18 variants, including the B18A1, B18A2, B18B1, and B18B2, weren’t equipped with VTEC, their high torque figures and strength still make them good candidates for modifications. The Honda B18C5 is the most sought-after U.S. variant due to its use of VTEC. 

Regardless of the variant, there is nearly unlimited aftermarket support for the Honda B18. Upgraded cams can transform a naturally aspirated B18 while also moving the power band to suit your needs. Turbo builds are one of the most common routes for many owners, as the B18 responds well to boost and can handle the additional power. Due to the fact that B-Series engines feature so many interchangeable parts, it is relatively easy and cost-effective to head swap a non-VTEC B18 with a DOHC VTEC head. While those three are common modifications, that is only the tip of the B18 aftermarket iceberg. 

If you enjoyed this article and are looking for more B-Series content, check out our Honda B16 Engine Guide! Additionally, we also have a Best Honda Engines of All Time article that covers some of Honda’s best powertrains in detail. As always, safe driving!