Honda L15 1.5 engine

Honda L15A/L15B engine characteristics

Honda L15 engine troubleshooting and repair

With the introduction of the Honda Fit to the market, a new series of Honda L engines were introduced, including the L12, L13 and L15 models. The most capacious of these was the L15A. This engine replaced Honda’s popular D15, which was slightly larger in size than the L15. The L15A has a 220 mm high aluminum cylinder block with a long-stroke crankshaft inside with a piston stroke of 89.4 mm, connecting rod length of 149 mm and piston compression height of 26.15 mm, giving a displacement of 1.5 liters.

This engine features a 16-valve timing with VTEC system that activates at 3,400 rpm. The intake manifold on the L15A VTEC is long and optimized for low to mid-range performance. The exhaust system is stainless steel with EGR.
The timing drive on the L15 is chain driven and requires no maintenance throughout its life.

There is also a two plugs per cylinder version known as i-DSI, with a cylinder head that has two valves per cylinder. These vehicles are designed with fuel economy and lower emissions in mind.

The L15 engines were fitted with dual camshaft timing and i-VTEC. In 2015, a turbocharged TD03 version of the L15B7 was introduced.

There are also cars with hybrid versions of L15 engines, designated as LEA and LEB.

A detailed description of each of these models can be found below.

It is recommended that owners of vehicles with L15 engines have their valves adjusted every 45,000 kilometers. Clearances for a cold engine are: intake – from 0.15 to 0.19 mm, exhaust – from 0.26 to 0.3 mm.

Modifications of the engine Honda L15

• L15A VTEC (L15A1) is a 16-valve SOHC head engine with a VTEC system. The exhaust diameter is 43 mm, compression ratio is 10.4, power output is 110 hp at 5800 rpm and torque is 143 Nm at 4800 rpm. It has been fitted to the Honda Fit, Mobilio, Airwave and Fit Aria.
• L15A i-DSI (L15A2) is an i-DSI motor that uses two plugs per cylinder. It has a SOHC head with two valves per cylinder, 38 mm exhaust diameter, 10.8 compression ratio, 90 hp at 5500 rpm and 131 Nm of torque at 2700 rpm. It was installed in Honda Fit Aria and City.
• L15A i-VTEC (L15A7) – The motor started production in 2007 and received improved intake and exhaust manifolds, newly designed pistons, lightened connecting rods, modified cooling system, and a revised 2-stage i-VTEC system on the intake valves, the intake valves were enlarged to 28 mm and the rockers were lightened. Power has increased to 117 hp at 6600 rpm and torque to 145 Nm at 4800 rpm.
• L15B (L15B1) – motor with DOHC head, with i-VTEC system and with variable valve timing system on the intake camshaft VTC. The intake valves are enlarged from 28mm to 29mm and the exhaust valves from 23mm to 25mm. The intake utilizes a plastic intake manifold. In addition, this motor is characterized by new pistons for compression ratio of 11.5, oil injectors, lightweight crankshaft with 4 counterweights. Power of such L15B1 is 130 hp at 6600 rpm, torque – 155 Nm at 4600 rpm.
• L15B Turbo (L15B7) is a turbocharged motor with direct fuel injection. The engine uses lightweight pistons, which are cooled by oil jets, compression ratio is 10.6. The block is covered with DOHC cylinder head with direct injection and with variable valve timing system on both shafts VTC. A small Mitsubishi TD03 turbine is used as a supercharger and the boost pressure is 1.15 bar. Power output of the L15B7 engine is 174 hp at 6,000 rpm and torque is 220 Nm at 1,700-5,500 rpm.
• L15B7 Civic Si is a refined L15B7, in which the compression ratio was lowered to 10.3 and supercharging pressure was increased to 1.4 bar. Power is 205 hp at 5,700 rpm and torque is 260 Nm at 2,100-5,000 rpm.
• L15Z – engine with 16-valve head with single camshaft (SOHC) and i-VTEC system. Compression ratio – 10.3, power – 120 hp at 6600 rpm, torque – 145 Nm at 4600 rpm. It is found on cars for South Africa and for Asian countries.
• LEA is the hybrid engine for the CR-Z and Fit Hybrid. It features a 16-valve SOHC head with an i-VTEC system on the intake valves that shifts at 2300 rpm. The intake uses a new intake manifold and electronic throttle, while the exhaust uses a finalized stainless steel exhaust system. With a compression ratio of 10.4, the LEA engine is rated at 122 hp at 6,000 rpm and 174 Nm of torque at 1,000-1,750 rpm. The power output of the electric motor is 13 hp and that of the engine is 113 hp. Since their maximum output is achieved in different ranges, the combined output is 122 hp.
• LEB is the hybrid engine for the Vezel. This engine uses a DOHC 16-valve head with i-VTEC system and direct injection. The compression ratio is 11.5, power output is 132 hp at 6600 rpm and torque is 156 Nm at 4600 rpm. Electric motor power – 30 hp. Total power – 152 hp at 6600 rpm, torque – 190 Nm at 4600 rpm.
• LEB – analog for Fit Hybrid, but working on the Atkinson cycle. The motor is equipped with distributed fuel injection and its compression ratio has been increased to 13.5. The LEB for Fit produces 100 hp at 6,000 rpm and 119 Nm of torque at 5,000 rpm.

Problems and shortcomings of Honda L15 engines

Reliability of engines L15A, L15B and other 1.5-liter L-motors is at the highest level, everything here is extremely reliable and serves hundreds of thousands of kilometers without problems. On the i-DSI, you need to change all the plugs when necessary, not just half of them. Otherwise, service in time, use quality oil, and the motor will not cause problems.

Honda L15 engine tuning

L15A Atmospheric

In general, tuning the L15 is a somewhat futile endeavor these days, as there are plenty of more powerful and faster cars, both atmospheric and with a small turbo, that with an inexpensive chip installed will outperform the Fit in performance. But if you have a desire to add power specifically to your L15A VTEC, it will require a cold intake, a larger diameter throttle, porting the cylinder head, installing a 4-2-1 manifold, a straight-through exhaust system, and purchasing a Greddy E-manage Ultimate. Once the motor is tuned, you can expect to see an increase in power to 130-135 hp. It is also possible to consider purchasing a camshaft, manifold, or 4-throttle intake system, but this is not always warranted. If you want more power, installing a K20 engine is recommended.

L15B Turbo

For the initially turbocharged L15B7 there are no problems – you can do chip tuning, which will raise the boost pressure to 1.6 bar and give up to 200 hp at the wheels. If you need more, then buy a cold intake, front intercooler, (which are enough for Civic 1.5 turbo), exhaust system and Hondata. With a maximum boost pressure of 1.8-1.85 bar, you can get 210-215 hp at the wheels.

Owning an atmospheric L15B, you can put a HKS turbo kit on it and increase power to 150+ hp. But that doesn’t make sense, the problem is that the kit with installation costs almost as much as a Fit. You could build it yourself and inflate it to 200hp, that’s the limit a stock motor usually holds, but it’s cheaper to change the car.

MOTOR RATING:5-