The engine is the heart of a car and so we focus first on the engine bay of the HMRT MME Civics. As far as the engine is concerned, item 3 of the 2004 MME Supplementary Technical Regulations states that 'Engine as supplied in the respective model may be modified, provided that the original intake manifold and throttle body or carburettors are used.'. So this means that the engine used in the race car must be the same series as that used on the road-car from which the race car is built. This rule is very crucial for the eligibility of Civic 2.0 i-VTEC in the MME.

Intake Manifolds Galore for the K20A 'Export' Accord 2.0l CR-V/Stream Accord/Torneo Euro-R Civic 2.0 i-VTEC/Type-R

The HMRT MME winning Civics uses the highly regarded K20A DOHC i-VTEC engine. This is the same base engine that is used on the Civic 2.0 i-VTEC road-car. In its most basic form, all the differences between the street engine and the race engine is their specs and level of tuning, which both the FIA Article 255 and MME ATR allows a lot of freedom. How wild the tuning goes is of course limited by the necessity for the engine to last 12-hours of continuous racing, from 10am in the morning through the highly stressful mid-day till 10pm at night. In a way, it is really correct to say that the MME K20A is the street K20A rebuilt for racing 'twice'. Let me explain what this statement means.

The actual base engine used is the R -spec K20A as used on the famous Type-R cars, in this case more specifically that from the DC5 Integra Type-R. We can actually look at this engine as a derivative of the same K20A engine used on the Civic 2.0 i-VTEC. Historically, the K20A engine was first used on the 2.0l Honda Stream way back in October 2000. TOVA actually translated the official Honda announcement of this engine as well as it's specs and usage in the Stream back then, the translation and our coverage being available in our i-VTEC article. A short while later, Honda published a technical overview of this engine on its official Japan web-site. Again TOVA published an english translation which included additional comments from us in our K20A article. As can be seen from both articles, the original K20A engine, the 'ancestor' so to speak, is an intake-only VTEC implementation, with 3 lobes on the intake cams allowing a 12V low-cam and 16V wild-cam mode. This engine also uses the dual runner intake manifold. Engine power was 154ps.

The DC5 Integra Type-R was launched by Honda on July 2001 and introduced to us the K20A Spec R (what we like to shorten to simply 'K20A-R' though of course such an engine code does not exist). This K20A-R uses VTEC on both intake and exhaust sides with 'full-time' 16V and VTEC changing between mild cam and wild cam for both intake and exhaust. There are of course many other areas of the engine that are different - valve springs rated to higher rpms, different (higher compression) pistons, crank, etc. But the gist is the two engines, the regular intake-only VTEC K20A and the racey K20A-R are really two different derivatives of the same basic engine, and the milder version was actually the first K20A engine used.

Honda also uses several quite different intake manifold designs for different applications of their K20A engines (for different models). The Stream and CR-V for e.g. uses a dual runner design but the 2.0 i-VTEC Accords uses a single runner design tuned for low end torque. Even the red-topped R-Spec K20As have more than 1 intake manifold design, the DC5 ITR and EP3 CTR for e.g. using a different design compared to the CL7 Accord and Torneo Euro-R. In this instance, the Civic 2.0 i-VTEC actually uses the same intake manifold design as the DC5 ITR and EP3 CTR. This is crucial for the Civic 2.0 i-VTEC's eligibility to compete in Class A of the 2004 MME since as highlighted above, the MME ATR requires the use of the 'original intake manifold' but goes on to allow the internals to be modified freely. And crucially, the difference between the intake manifold of the Civic 2.0 i-VTEC and that of the DC5 ITR is all in the inside. So as can be clearly seen now, the base DC5 K20A-R that is used for the HMRT MME Civics can quite accurately be described as a 'built and tuned' version of the basic K20A that is used on the road-car, all the internal modifications being permitted by both FIA Article 255 and the MME 2004 ATR. I.e. the base K20A-R can really be seen as a '1st level' rebuild of the base K20A. Honda Malaysia could have build the K20A-R from the road car's K20A to use for the race but it is more straightforward & cost-effective to start with an original K20A-R instead.

 

To maximize their competitiveness in the MME, the K20A-R engines are further modified. This is actually done by sending the stock K20A-R engine (only) to the famous M-TEC (Mugen) company of Japan for special prepping for endurance racing. This then is why I say the MME engines can be seen as '2-level rebuilt' versions; the K20A-R representing a 'level-1' rebuilt and the Mugen prepping representing the 'level-2' rebuilt of the base Civic 2.0 i-VTEC's K20A engine. Take a close look at the two photos of the road-spec K20A and the MME-spec 'Mugen K20A-R' above and one can clearly see they are practically identical, including the intake manifold designs; all the 'goodies' being on the inside !

Having explained the origin and rationale of the engine, I will cover the more interesting parts of the engine bay using pictures and technical narrations. For each photo below, click on it to get an SVGA high-res version.

Mugen Built K20A When I first heard that the K20A engines on the HMRT MME Civics are prepped by Mugen, my immediate reaction was Fit Dynamite ! and that the engines would be delivering at least 260ps or more. However the HMRT race engineers told me that the engines are not very much higher spec than the original K20A-Rs. They were mainly balanced and blue-printed, with selected components upgraded for endurance racing. The power ratings of the engines are actually very near the original engines. While stock DC5 K20A-R delivers 220ps at 8000rpm, the MME version Mugen rebuilt for HMRT are rated at less than 240ps also at 8000rpm. This represents a less than 10% power increase ! When I first heard the figure, it was a mixture of surprise and dissapointment (I had expected figures hovering around 300ps) but the race engineer told me Mugen thinks this power level is sufficient to compete successfully in the MME (and of course they were proven correct). While stock K20A-Rs revs to 8,500rpm, the MME engines were instead rev-limited at 8,250pm to ensure they last for the whole 12-hours of the race. I also confirmed that i-VTEC was active in the race engines, in fact i-VTEC gave Honda an advantage as it allows a good level of fuel economy and a good broad power delivery from the engines and as explained in my race coverage, their good fuel consumption was one of the crucial advantage the MME Civics had over their immediate competitors.

Engine Oil Idemitsu engine oil was used on the Mugen K20A-Rs. Honda VTEC engines are well known to consume a moderate amount of engine oil and the HMRT MME Civics actually consumed around 1 litre of engine oil during the race. Towards the latter half of the race, one of the Team Kunimitsu engineers checked the engine oil level of both cars during every of their pit-stop. A top-up was required somewhere towards the ending stages of the race. Interestingly, engine oil was poured from a small 0.5l mineral water plastic bottle. This allowed the top-up to be done directly from the bottle without having to use a funnel - there's no time for niceties in the race ! According to HMRT, the lack of engine oil was actually felt by the drivers - in the turns where the G-force from hard cornering forced engine oil to one side of the engine and caused an artificial low oil pressure condition and this caused VTEC to not 'open'. The engine then bogs at WOT during corner exits and gradually as the track straightens out then only oil pressure returned to normal. Now VTEC suddenly activates causing a surge in engine power, and this is felt by the driver in the form of a sudden urge in the car's pick-up. I was also very surprised at the lack of an engine oil cooler for the cars. The radiators from the DC5 ITRs were carried over and used on the Civics and according to HMRT, this stock cooling system was quite good enough for the race !

Gearbox For the gearbox, the gearboxes from the DC5 Integra Type-R were used in their original forms for the race. They were not rebuilt and all the original 6 gears and their ratios are used, including the final drive. HMRT did disassemble them for overhaul to ensure they are in tip-top condition to last the 12 hours of the race. The standard 'Type-R' helical LSDs were however replaced with race-spec Mugen 2-way LSDs. While the engines were in Japan being re-built by Mugen, HMRT mechanics actually spent many nights in the Honda Malaysia Sales and Service HQ in P.J. over-hauling the gearboxes. I was also surprised to learn that the gearbox is fitted with an oil cooler. Since the gearbox oil is not pressurized, an external oil pump was fitted to route the oil to an external cooling coil, the black coloured unit fitted in front of the radiator. The oil pump is the round metal cylinder in the first photo. Mugen has a 'Mission Cooler Set' which they supply to Honda One-make Race race-cars in Japan and this is probably what is used in the MME Civics.

Power Steering The other silver coloured cooling coil fitted in front of the radiator is for cooling the power steering fluid. I.e. the hydraulics power steering system is carried over from the DC5 ITR as well. I was surprised why the EPS of the Civic wasn't used since it would incur less stress on the engine and allows slightly more power to be delivered to the wheels too. From what I could understand, the EPS on the Civic 2.0 i-VTEC is set for comfort and not all out performance driving. This includes the amount of steering assist as well as steering response (i.e. how much the car turns in response to steering wheel input). While the EPS could theoretically be re-tuned for the MME, it was decided that the stock DC5 ITR system was already nicely tuned for racing and so was retained.

Mugen Racing Suction Kit Other than the red-top K20A engine, the most conspicuous item in the engine bay is the Mugen Racing Suction Kit. This is a special 'cold air intake' system for the air-filter, designed for racing use only and with a very nice Mugen logo on the cover. The air-filter is enclosed in a specially designed box to keep out the hot air of the engine bay and cold outside air is routed in from the bottom via hoses. This system is shown clearly on the two photos on the left.

Spark Plugs and Oil Catch Tank The other obviously 'Mugen' item on the engine would be the spark plug cables & ignition coils. Just like the DC5 ITRs of last year, the red-top K20A-R on the HMRT MME Civics has Mugen logos on the top of the ignition coils. An Oil Catch Tank is also fitted to the engine, the aluminium canister that 'catches' the engine oil blowing out of the PCV valve being mounted on the 'fire-wall' right where the chassis code is engraved (if there's one). The oil-catch tank seems to be a 'mandatory' item on Hondas spec'ed for endurance racing as I have seen it used in last year's Kunimitsu DC5s (also with Mugen built K20A-Rs) as well as both the Spoon endurance CL7 Accord Euro-R and Racing Fit. But unlike those race-cars, the HMRT MME Civic does not feature a 'power earthing system'. In fact, the battery is not even located in the engine bay and has been relocated to inside the cabin.

Mugen Exhaust System For the rest of the engine 'tuning', the exhaust system is of course of the racing spec type. The muffler is a Mugen straight-flow with the nice 'Mugen' badge welded on it. The tail-pipe unusually points downwards. The headers seems to be the original stock item and the heat shield is still bolted on.