Honda Prelude H22 Jackson Racing Supercharger (JRSC): Preparation and Installation

Before committing to forced induction, verify the shortblock and valvetrain are healthy. Resolve any check-engine codes first. Then run a compression or leak-down test: sound cylinders read about 190 psi give or take 20 psi, with a strong result near 200 psi. Any cylinder outside that window, especially a low one, points to a rebuild before boosting. Measure valve lash while you are in there; a top end noisier than the usual light ticking is overdue for adjustment. Finally, inspect the clutch and transmission, because extra torque quickly exposes a slipping clutch or a grinding gearbox. Automatics are fragile behind a supercharger, so a manual conversion is the durable fix and a transmission cooler is only a stopgap.

Set the valve clearances now, before the supercharger goes on. Once the plenum, jackshaft, and bracketry occupy the top of the engine, pulling the valve cover becomes a major job. Do this even if the lash currently seems fine, since you will not want to revisit it after the kit is installed.

Most of the mounting bolts sit behind the accessory drive, so the signature tool is a stacked extension, u-joint, and socket combination that reaches them. Use a shallow 12 mm swivel/wobble socket for the supercharger bolts (some kits use 13 mm), paired with a thin 1/4-inch extension so it clears. Also gather Allen keys around 5 mm, 6 mm, and 5.5 mm, blue hand-serviceable threadlocker, high-temperature silicone gasket maker, a 14 mm flare-nut wrench for fuel fittings, a 1.5-inch fan-clutch wrench for the snout pulley nut, and a drill with a 5/8-inch bit. A ratcheting wrench can outperform a swivel on some of these fasteners.

Confirm every mandatory Jackson Racing component is present before you start; a kit missing any of these is not worth buying. Grouped by function, the non-negotiable pieces and their part numbers break down as follows. The charger assembly proper covers the supercharger itself (051-605), its S-tube (051-606), the plenum (051-607), the bypass valve (051-098), and the adapter plate (051-624). To drive it you need the jackshaft carrying a 1.75-inch pulley (988-104 / 051-616), paired with its belt tensioner (051-609). Mounting the whole assembly then calls for the pulley bracket (988-103), the alternator spacer (051-611), the lower spacer-to-bracket support (051-612), and the metal idler pulley (051-816). Rounding out the list, you also need four nylon idler pulleys with hardware (051-627), plus bearings and a retaining snap ring for that metal idler.

Swap the fuel filter before the supercharger is mounted, because the jackshaft assembly later blocks access to it. Relieve fuel-system pressure, then use the 14 mm flare-nut wrench to avoid rounding the fittings. An OEM Honda filter is fine for most builds; a steel-element filter is worth considering if you run E85.

Two gaskets seal the plenum: a large square one seated between the adapter plate and plenum, and a smaller ported one below the plenum where it meets the lower intake manifold. Cut them from 1/8-inch Teflon, which insulates against heat, is easy to work, and creeps to fill minor surface imperfections. Printed stencil scans are available; print at Letter size, since A4 will not scale correctly. Before cutting, verify the colored field on the large gasket measures 8.25" x 10.75" and the small ported gasket measures 8" x 10". A sharp knife cuts cleaner than a rotary tool.

If you are changing the intake manifold or fitting an insulating gasket, remove the baked-on paper gasket from the mating surface. 3M Roloc bristle discs on a variable-speed drill clear it quickly; the coarse green discs are fastest but can lightly mar the surface, while the medium or fine discs are gentler and more forgiving. A razor blade with brake cleaner and a ScotchBrite pad also works but is slow, and an aerosol gasket remover paired with a blade is another option some builders prefer.

Follow Jackson Racing's supplied instructions for the core bolt-up, using the extension and u-joint setup on the hidden fasteners. Removing and refitting the jackshaft together with its bracket as a single unit saves effort. Apply blue threadlocker to the pulley-bracket bolts. After torquing, confirm with the 1.5-inch wrench that the snout pulley nut is fully seated: a pulley left unseated throws the belt out of alignment and shreds the short belt in short order. Run four plastic idlers plus the single metal idler on the pulley bracket to keep belt slip under control.

Boost is dialed in through pulley diameters. A 3.36-inch snout pulley is close to stock, while a 2.95-inch snout, sourced from a Ford Focus SVT, adds roughly 3 psi. Fitting a 2-inch second jackshaft pulley adds about another 3 psi. Source replacement pulleys from ENDYN, Motorvations Motorsports, or Moss Motors; McMaster-Carr part 6235K62 is a cheaper pulley that suits builds without power steering.

The kit displaces the manifold-absolute-pressure sensor and the idle air control valve. Fit the MAP block-off/relocator (051-834) and route a post-supercharger boost and vacuum reference to the sensor; this is essential for nearly every engine-management setup. Install the IACV relocator (988-056) to preserve idle control. Rosko offers replacements for both brackets.

The management hardware in the original kit is inadequate and should be used only where a CARB-compliant appearance is legally required. For a proper tune, Neptune RTP works but needs an OBD2-to-OBD1 ECU swap, which rules it out where emissions testing plugs into the ECU; Hondata and Chrome are alternatives. Where an emissions plug-in is mandatory, a discreetly installed GReddy E-manage Ultimate allows real tuning. Support the fuel side with a Walbro 255LPH pump, Injector Dynamics ID750cc injectors (step up to ID1000cc for E85), an Aeromotive regulator, and a multi-port fuel rail such as AEM's.

Air leaving the supercharger is hot, and hot intake air hurts both power and safety margin. An LHT intercooler built on Laminova cores is the established option for the tight Prelude engine bay. Water/methanol injection is an alternative that reliably lowers intake temperatures, though community reports on its power gains are mixed.