How To: Installing a 2.3 Aerio Engine Into A Sidekick Sport
By: Matt Verley, Photography: Matt Verley
Seaside, OR – Over the last 20 years, I have owned at least a dozen Samurais, several Sidekicks and Trackers, and a couple of Vitara and Grand Vitara. About 3 years ago, I stumbled across a 1996 Sidekick Sport with a blown engine in my local classifieds. Though I had never owned a Sport, I knew a little about the sub model and I knew where an “almost new” replacement 1.8L engine was located so I called the seller, made the deal, and ran into town with my truck and trailer. The following weekend, I had the replacement 1.8L engine under the hood and running, and the Sport turned into a daily driver for my wife for the next 3 years.
Earlier this year, I came across a deal on a 2006 Grand Vitara. My wife took it for a test drive and the rest is history; she had a new daily driver, and the Sport moved down to the parking lot by my shop. I started driving the Sport to some off-road trips; mostly mild 4×4 trails, fire roads, and desert-type trails. While the 1.8L engine offered a good horsepower upgrade from either of the 1.6’s, it lacked that low end “grunt” I like in my off-road vehicles. It made good power above 4500 RPM and high speed freeway/highway performance was good, but lower RPM performance was…disappointing. I began searching for a way to add some extra horsepower; I considered forced induction, engine modifications, complete engine swaps, and more. Then I came across the solution: A J23 2.3L engine swap from a 2004-2007 Suzuki Aerio. The 1.8L is rated at around 118HP (depending on the source; I found a few different numbers) and the 2.3L is rated at around 158HP (again, depending on the source). But the peak HP numbers don’t tell the entire story; it is where the engine develops the power that was more important to me. I was really after more power at lower RPM, and the 2.3L delivers a significant gain in this area.
I did the normal forum and google research; I found conflicting information about which flywheels would work, whether or not the bell housing pattern was the same, if the 1.8’s ECU would work or if I needed to swap to the 2.3 ECU, if the crankshaft position sensor reluctor wheel had the same number of teeth, if the cam position sensor was the same, etc. Since the 1.8 and 2.3 are both from the same “J” series, I was hopeful that the swap would be relatively easy. I decided there was only one way to find out for sure, so I bought a running 2004 Aerio and brought it home.
I spent an entire weekend stripping the Aerio of its parts; the engine and transaxle came out from underneath the vehicle with relative ease, but the removal of the wiring harness from behind the dash proved to be very time consuming. I was planning on parting out the Aerio, but the first person to come for parts ended up purchasing the entire vehicle to rebuild his wrecked Aerio. When it was all over, I ended up with a low-mile engine, wiring harness, ECU, and most of the under hood parts for just a few hundred $$.
I pulled the 1.8 out of the Sidekick and put both engines side by side to determine what needed to be swapped over. Below is a list of items that I ended up with on the 2.3:
- 1.8L flywheel and clutch
- 1.8L coolant tube and cast coolant head adapter and associated sensors
- 1.8L driver and passenger side engine mounts
- 1.8L exhaust manifold
- 1.8L A/C pump and mounting bracket (the 2.3L one is different but would work fine; I didn’t want to change it because I left the AC system intact on the sidekick with the pump still connected to the lines and didn’t want to have to re-charge the system. The 1.8L bracket also has provisions for a mechanical fan; I’m running electric so that didn’t matter to me)
- 1.8L water pump (the 2.3’s water pump looks identical, but I had replaced the 1.8’s about a year earlier so I decided to use it)
- 2.3L crankshaft pulley (If I was running the mechanical fan I would need to run the 1.8 pulley)
- 1.8L power steering pump and brackets
- 1.8L alternator and brackets
- 1.8L coolant manifold and lift eye
- 1.8L intake manifold and all associated sensors
- 1.8L engine wiring harness
- 1.8L coil packs
- 2.3L fuel injectors, fuel pressure regulator, fuel rail, and injector harness
- 2.3L crankshaft position sensor
- 2.3L camshaft position sensor
- 1.8L oil pan
- 1.8L oil pickup tube
While I had the engine on the stand, I took the time to replace both front and rear crankshaft seals. Once all of the accessories were swapped onto the 2.3L engine, installation was simple, straightforward, and fast. After just a couple of hours I had the engine in place, wiring all plugged in, and fuel and exhaust plumbed. I was ready to turn the key! After just a couple of seconds of cranking, the engine fired right up and settled into a steady idle. I didn’t run it for long because I didn’t have the radiator in place and I didn’t want to cause hot spots in the head or cylinder walls. But, it was enough to tell me that it was going to run!
After a few more hours of wrench turning, I had the radiator installed and everything under the hood completely buttoned up and ready for a test drive. The power increase was very noticeable; the 2.3L makes considerably more power at all RPM but the most notable difference was at the lower RPMs. I did some full-throttle pulls from 0-80 MPH to listen for any pinging or detonation, but I was unable to detect any issues. After about 40 miles of rural highway and gravel road driving, I went to an undisclosed location for some more aggressive driving. I managed to hit the 100 MPH mark on flat ground; a speed that was previously unattainable with the 1.8L. This speed is impressive, considering the 5” lift and 32” tires.
I had pulled the 2.3L ECU and wiring harness knowing that I might need to swap it into the Sidekick to get the new engine to run properly, but the 1.8 ECU seems to make the 2.3L engine run just fine. With that being said, there is probably a bit of power hiding in the 2.3L ECU; the 1.8 doesn’t make use of a knock sensor, so I’m guessing that the 2.3L ECU can tighten up the AFR and timing curves a bit. Its fuel map is probably better suited to the 2.3L as well. But, while I’m certain there is a little bit of power to be gained by swapping to the 2.3L ECU, the gains may not be worth the effort involved.
Since completing the swap, I have driven the Sidekick for a little over 500 miles. This includes a mix of freeway, highway, gravel, deep snow, and one “off-road rescue” run. The extra power is a welcome change; the passing lane is now a useful lane for the Sidekick, and uphill passes are no longer wishful thinking! While the Sport is certainly no drag racer, this engine brings it into the “adequately powered” category. I have filled the fuel tank 3 times and am seeing economy numbers consistent with what I would expect from the 1.8 in the same types of driving. I am very happy with the results; in fact, I regret not completing this project sooner!
During the swap, I set up the cameras and filmed the entire process. I put together a shortened video here, complete with a test drive at the end of the video: