This can be quite a difficult change if you try it without instructions or guidance. However, these step-by-step instructions can make it a breeze. An H22 engine in an 88-91 civic or CRX chassis exaggerates the old power-to-weight theory for incredible acceleration.
Let’s start by assuming you’ve already removed the stock engine. We will begin this engine change by preparing the engine compartment. The first step is to remove the passenger side transmission mounting bracket that is welded to the frame. The use of a drill with a large bit or a spot weld bit will be required to pierce the factory welds and remove this bracket from the frame rail. After removal, use a grinder or similar tool to smooth the frame rail of any debris or sharp points left from the drill.
Next, bolt the passenger side drive bracket included in the Hasport mounting kit to the passenger side frame rail using the 12mm battery tray bolts and factory tapped holes. You will need to use a Sharpie marker or other marker to trace the outline of this bracket on the railing. Remove the backing and grind or sand the paint from the area you traced to prepare it for welding.
Screw the bracket back into place and weld the bracket to the frame rail. Be careful to fully penetrate the solder, but do not burn through the factory frame rail. After the area has cooled, spray primer over exposed welds and apply paint of your choice of color over the primed area to prevent corrosion.
Then comes the tricky part. Factory F / H series transmissions are very large and will require some modifications to the bottom of the rail under the newly installed bracket. It’s easier if you partially lift the motor into place to see which area needs to be cut. After cutting enough space, you will need to fabricate a brace from sheet metal or similar material to properly reinforce the frame rail. This can be omitted, but be aware!
Now for some fun things. By now you will have overcome the fear of cutting your car, so this will be very simple. Use a medium sized mallet and make a large dent in the top of the firewall to make room for the huge H22 intake manifold. It may be helpful to partially lift the motor into place to get an idea of where to “place” this dent.
Screw the rear Hasport bracket onto the lower cross member using the supplied hardware included with the Hasport bracket kit. On the timing belt side of your new H22 engine, remove the timing belt covers and unscrew the mounting bracket from the factory engine. Screw the new Hasport engine mounting bracket into place and reinstall the factory timing covers. Covers may need slight trimming to clear ticket port mounting bracket.
Remove vehicle speed sensor from H22 transmission and replace with factory 88-91 civic / crx cable actuated speed sensor. This should snap directly into place. Bolt the Hasport cable to the hydraulic conversion lever assembly on your H22 transmission. Due to the large size of the H22 engine, you will need to shave off the outer power steering pulley or install a low-drive style crankshaft pulley that does not have a power steering groove.
Screw the included Hasport alternator bracket onto your h22 engine using the hardware supplied with the Hasport H22 mounting kit. Then screw the factory D series alternator bracket to the Hasport alternator bracket. The dipstick tube may need to be bent slightly to allow clearance. Using the remaining factory hardware, screw your original D-series alternator “backwards” onto your H22 engine. To facilitate installation in the engine compartment, you can wait until the engine is installed to screw in the alternator.
Now comes the fun part. The easiest way to install an H22 engine with a Hasport mounting kit is from the bottom. You will need to lift the car on a forklift and “lower” it toward the engine. When the motor is almost in place, screw the rear motor “L” bracket in place using only the top two bolts. Leave the bottom two rear bracket bolts out until the other brackets are screwed in. You can now screw the timing belt side bracket into place, followed by the drive bracket. Just hand tighten them for now. Go back to the rear bracket that bolts the engine to the rear bracket and install the two lower bolts. Now tighten all of the engine mount bolts to factory specifications.
For wiring, you will need to modify the original motor harness to fit the Prelude motor. For simplicity, a new custom wiring harness can also be purchased. The shafts you will need to use are custom made by Hasport and will be installed using the H22 intermediate shaft.