There are several engine options for you to choose from. Just one of many points which make the subaru engines an ideal replacement for the vanagon engine is that they share the same 'boxer' format, the flat opposed-cylinder layout.
The original 2.2 liter engine is the original conversion pioneered by Kennedy, and it offers a healthy increase in power and transforms the vanagon into a modern vehicle. The 2.5 liter is arguably the ideal powerplant for the vanagon with its smooth, balanced power and enough torque to conquer the hills. The SVX offers all the power you could want, the most power of any commonly available engine conversion for vanagon.
Here are some technical details and history of the engines we put into vanagons:
EJ22: 2.2 liter, 135 hp 4-cylinder
Subaru's bread and butter engine from the 1990s. Arguably their most bulletproof. Extremely smooth and reliable. These engines regularly go hundreds of thousands of miles - typically only body damage puts them into the wrecking yard. The early version of this engine is a non-interference design, which means that if the timing belt fails no engine damage occurs.
Opposed boxer four cylinder engine, 2.2 liter displacement. Distinguished by small valve covers, about 5 inches tall, and an “EJ22” stamp visible on the block to the left of the alternator. (Beware the EJ18, a lower hp engine which looks very similar and appeared in early Imprezas.) The EJ22 was produced from late 1989 through 2001. Phase I engines were produced through 1998.
The earliest phase I engines, through 1994, generated maximum 130 hp at 5600 rpm and a healthy 137 ft-lb torque at 4400 rpm. These engines had dual exhaust ports and were non-interference.
For 1995 and 1996, the horsepower and torque increased slightly to 135 hp at 5600 rpm and peak 140 ft-lb at a lower 4000 rpm. Some 1996 EJ22 engines already had the single exhaust port like later models. Starting in 1995, subaru added OBD-II engine diagnostics and are identified by the addition of an EGR tube to one head.
The late phase I engines in 1997 and 1998 increased in power to 137 hp at 5400 rpm and 145 ft-lb at 4000 rpm. These longblocks are identical to the earlier engines except they had standard single exhaust ports and slight changes to the internals made it an interference engine.
Phase II EJ22 engines, installed from 1999 through 2001 only in the Impreza car, were rated at 142 hp at 5600 rpm and 149 ft-lb torque at an even lower peak of just 3600 rpm. These engines are also an interference design with single exhaust ports, and share little of their design and parts with the Phase I engine. However, they do share a number of parts with the phase II EJ25 engine, in typical subaru fashion.
EJ25: 2.5 liter 170 hp 4-cylinder
Subaru's new bread and butter engine for the new decade. The phase II engine appears in Impreza, Forester, Legacy, and Baja since the middle of 1999 and has proven to be extremely reliable. More stock, factory tuned power and torque than any other non-subaru engine choice commonly available for the Vanagon. This engine is an interference design, so regular timing belt changes at 100,000 miles are a necessity.
Opposed boxer four cylinder engine, 2.5 liter displacement. Distinguished by tall valve covers, around 10 inches high, and an “EJ25” stamp visible on the block to the left of the alternator.
Phase I engines were double-overhead cam, appeared in Legacy and Forester from 1996 through 1999, and were rated at only 155 hp in the first year, and 165 hp afterward. We never used this engine and do not recommend conversions with this engine.
Phase II engines changed to a single overhead cam design and produced the same 165 hp at 5600 rpm and 165 lb-ft torque at 4000 rpm through 2005.
The newer drive-by-wire engines from 2006 now have variable valve timing and make 170hp. We are currently using this engine for our conversions.