The most famous Honda VTEC fours can be found in Civics, Integras and S2000s. But what about the Prelude and its similarly sized cousins found in the Japanese market? These vehicles can be bought with H-series 2.2 or 2.3-litre VTEC engines (the biggest VTEC fours ever made) and they’re s-o underrated it’s not funny.
We take a look at the ‘big block’ Honda VTEC fours...
Honda H-Series Engines
The first application for the H-series four-cylinder was in the nose of the Japanese market Honda Prelude Si VTEC of late 1991.
Using a 87mm bore and 90.7mm stroke, the BB1/BB4 Prelude’s H22A engine displaces a total of 2156cc. The engine is equipped with a DOHC, four-valve-per-cylinder head with PGM-FI multi-point injection system and a distributor ignition system. But more important is the VTEC variable valve timing and lift system that lets the engine produce great top-end power – try 147kW at 6800 rpm and 219Nm at 5500 rpm. The compression ratio of the VTEC H22A is set to 10.6:1 which requires the use of premium unleaded fuel.
The H-series engine is designed for transverse mounting and, in the Prelude, is available with either a five-speed manual gearbox or a four-speed auto. Drive is to the front wheels.
In 1992, the same engine design was re-released to incorporate a 95mm stroke - this increases swept capacity to 2258cc (2.3-litre). Unfortunately, the newly created H23A engine doesn’t get VTEC breathing and employs a lower compression ratio (9.8:1). Despite its slightly increased capacity, the H23A trails the output of the VTEC H22A by a considerable margin - peak power is 121kW and there's 211Nm of torque. Note that these figures are achieved at much lower revs – 5800 and 4500 rpm respectively. This engine comes fitted to the top-of-the-range Japanese market CC4/CC5 Ascot Innova hardtop sedan. Most are fitted with automatic transmissions.
In Australia, the H-series engine was first seen in Prelude of late 1991. However, unlike Japanese models, the first examples were sold with the non-VTEC H23A (as used Ascot Innova). In Australian guise, the H23A is rated at 118kW at 5800 rpm and 209Nm at 4500 rpm. A 96kW 2.2-litre F22A was also introduced in the base model – this is not to be confused with the more powerful H-series! The Australian market had to wait until 1994 to receive the muscular VTEC H22A. With 142kW at 6800 rpm and 212Nm at 5250 rpm on local premium unleaded fuel, the 1300+ kilogram VTEC equipped Prelude VTi-R can accelerate to 100 km/h in 8-seconds.
In Japan during 1993, the VTEC H22A made an appearance in a second vehicle - the high performance version of the CD6 Honda Accord Si-R. The Accord Si-R engine has the same specs as the go-fast Prelude but output is reduced slightly to 140kW/206Nm. This is possibly due to a more restrictive exhaust system. Like the Prelude, five-speed manuals or four-speed autos are available. Interestingly, an auto-only coupe version of the Accord Si-R was also introduced during 1994 and a wagon Si-R model appeared in 1996 (chassis codes CD8 and CF2 respectively).
The updated BB6 Prelude Si-R appeared for the 1997 model year bringing an optional sports-shift auto trans and Honda’s ATTS (Active Torque Transfer System) but, curiously, it appears Japanese versions have no extra power.
In contrast, the 1997 Australian-delivered Prelude underwent significant changes. The non-VTEC H23A was dropped and a revised 118kW F22A engine was used in its place. The existing VTEC H22A was updated with a new open-deck block, fibre reinforced metal cylinder liners (achieving better heat dispersion and reduced weight), full floating pistons, an aluminium oil pan and improved intake and exhaust flow. These changes raised output to 143kW (a 1kW gain over the previous generation Australian-spec H22A). An update in late ’98 lifted power further to 147kW. Like Japanese models, a sports-shift auto and ATTS could be specified in the Prelude from 1997.
The biggest development during 1997 was release of the Japanese market Prelude Si-R Type S. The Type S has a hotter version of the VTEC H22A incorporating a 11:1 compression pistons, a ported head, larger throttle body, altered cams and VTEC characteristics, a low restriction intake system and improved headers/exhaust. These changes achieve some healthy gains – 162kW at 7200 rpm and 221Nm at 6700 rpm. The same engine was then released in the 2000 ‘new generation’ GH-CL Honda Accord Euro R and 2000 Torneo Euro R. We believe the Prelude Si-R Type S, Accord Euro R and Torneo Euro R come with only a five-speed manual ‘box. A red valve cover identifies these high-spec engines.
About now you may be wondering whether the long-stroke H23A can be combined with VTEC variable valve lift and timing. Well, the Japanese market Honda Accord wagon Si-R of 1999 (chassis code CH9) proves it can be done...
The ’99 Accord wagon Si-R packs a VTEC H23A engine with a relatively mild tune and a 10.6:1 compression ratio (0.4 lower than used in the Prelude Si-R Type S). Somewhat disappointingly, the VTEC H23A makes hardly any more grunt than the original VTEC H22A - 147kW at 6800 rpm and 221Nm at 5300 rpm. A four-speed sports-shift automatic transmission comes standard and an AWD driveline was available from 2000 (CL2 chassis code).
Interestingly, the H-series four was never used in anything other than the Prelude, Accord, Ascot Innova and Torneo Euro R. Production ended when the K-series four appeared in 2002. It’s difficult to understand why the H-series VTEC engines – the biggest of all Honda VTEC fours – are largely underrated. They have proven very reliable (early ‘90s Prelude VTi-Rs are still going strong) and they’re one of the ultimate atmo fours on the market. From a tuning perspectively, it’s unlikely you’ll find much more power with conventional tuning methods – maybe 10 percent – so it’s you’ll need to add forced induction or a multi-stage nitrous kit to give these engines a significant boost throughout the rev range. Fortunately, it’s never been cheaper or easier to add a turbo...