Honda City VTEC Preview


The new Honda City is probably the most successful model marketed by Honda in the ASEAN region. It is a bold new model, featuring what many Honda fans considers a 'futuristic design' that is based largely on the platform of the highly successful Honda Fit/Jazz. Coming out of Honda R&D Asia in Thailand, it was originally launched in only 1 variant, what has now come to be called the 'City i-DSI' featuring the new L15A 1.5l i-DSI engine. I have reviewed the Honda City i-DSI extensively here on TOVA, it is an excellent vehicle with plenty of 'go' and superb fuel economy - a fine all-rounded vehicle. Early this year, Honda Asia launched a new variant, the Honda City 1.5l VTEC. This new VTEC variant turned the City range into a 2 variants line-up by adding the much eagerly awaited performance-oriented variant, what might be called a City 'sports sedan'. Launched first in Thailand as usual, for Malaysia it was launched back in late-July by Honda Malaysia, a very awaited event by Honda and City enthusiasts. A short while after attending the launching, around early August, I got the invitation to attend the City VTEC's media test-drive session to be held at the hill-top resort of Bukit Tinggi. It was a very interesting session where Honda Malaysia also brought in some engineers from Honda R&D who designed the City VTEC to participate.

Timing-wise, the City VTEC launch and media preview was placed smack into the exciting and hectic period where Honda Malaysia was developing their MME Race Civic. Then there was the excitement of being able to cover the HMRT race from their pits at Sepang, the race report and finally the big scoop on the technical coverage of the MME Civics themselves. As a result, I had no time to cover the City VTEC launch at all. I had a number of readers especially in ASEAN impatiently asking me when I intend to review this new City VTEC. I think some might even have given up waiting for it. To everyone who were waiting, I do extend my sincere apologies. Now that I have time to catch up with my quite considerable backlog, here then is my review of the new Honda City 1.5l VTEC.

Technical Coverage

First of all, let's take a close look at the new City VTEC from the mechanical point of view. The obvious approach would be to compare it to the i-DSI version. In this comparison, the main differences between the i-DSI and the VTEC version centers on 3 main areas : engine-gearbox, suspension-brakes, and the rest of the car.

On the new City VTEC, the star is undoubtedly the L15A VTEC engine. This is a 16V SOHC VTEC version of the L15A. It is rated for 110ps compared to 88ps of the i-DSI and has 4 extra valves and VTEC but without i-DSI, using the standard 1 spark-plug per cylinder. VTEC is implemented on the intake side only and it is a 12V-16V VTEC mechanism, implemented via a 2-rocker/2-cam lobe arrangement that is now more or less standard on Honda's intake-only VTEC engines, including the K-series. This mechanism was first used on the 1.5l D15B SOHC VTEC-E engine on the 1991-1995 EG8 Honda Civic ETi, an engine focussed for maximum fuel economy. However, associating this 2 rocker-2 camlobe system as a VTEC implementation solely for fuel economy would be wrong. On the current generation of K and L series engines, it is used for a balance of good power with good consumption (economy); the 12V mode targetting max possible fuel economy and the 16V mode targetting max possible power.

The 2 rocker-arm mechanism is shown clearly on the photo on the right. This photo of the rocker-arm mechanism is taken from a real cutaway engine Honda Malaysia displayed at the Honda City VTEC launch event at the 1Utama shopping mall. On the 'VTEC
off' mode, the two rocker arms works independently, driven by 2 separate cam lobes on the single camshaft. However, only 1 of the cam lobe has a profile that works the valve, the other is a flat ring that leaves its rocker arm motionless and the associated valve inactive. 'VTEC on' mode locks the 2 rocker arms together and now both rocker arm and both intake valves are driven by the working cam lobe.

The L-series engines are of course designs which emphasize on fuel economy. The i-DSI dual spark system is designed to enhance combustion of the air-fuel mixture - for more complete combustion and thus get maximum mileage. The L15A VTEC engine is this same basic design but now re-spec'ed for maximum possible power output without sacrificing too much in fuel economy and most importantly with the engine still ULEV compliant. To see the level of tuning adopted for this 2 rocker/cam-lobe VTEC in the proper perspective, think of it as a 1-'wild' and 2-'wild' cams mode. In 'VTEC-off', there is 1 'wild' cam-lobe working 1 rocker arm and of course 1 of the intake valves. With VTEC 'on', both rocker arms are now being driven by the same cam-lobe and so effectively it's like 2 rocker arms both working with a 'wild' cam profile. While it is not totally possible, this mode do give a good approximation to doubling the amount of air-flow into the engine once VTEC activates both rocker arms. I asked the Honda R&D engineer in charge of the engine for the VTEC changeover point and was told it varies depending on the throttle position. The change points are 2,300rpm for full throttle and 3,400rpm if partial throttle.

The camshaft-valvetrain is not the only change to the L15A to generate the extra 22ps. The intake manifold itself is different on the L15A-VTEC, having larger runners for more air-flow at higher-rpms. Internally, the engine also features some additional enhancements like aluminium roller-rocker arm assembles for lower operating friction and thus less power loss through internal friction. The exhaust system has been enlarged for a higher flow-rate to cater for the higher power delivery.

Now in the absolute term, the 110ps of the City VTEC's L15A engine may not be a fantastic level of power output. But then, it is also important to have a sense of perspective. For the market segment at which the City i-DSI and City VTEC is targetted at, 110ps in relative terms is really very high power. The 1.5l DOHC VVT-i Toyota Vios with 109ps used to dominate this segment for max power but this new City VTEC is now right at the top of all cars available in the segment. In relation to the original City i-DSI, one needs to bear in mind that 110ps represents a 22ps increase and that is a massive 25% power increase ! So for the general choices available in this market segment, for e.g. the owners of the original City i-DSI who have been 'making do' with 'only' 88ps, 110ps is really a lot of power.

Compared to the 88ps i-DSI engine, the VTEC engine delivers in the upper mid to high rpms. Indeed, at rpms below 3,000, the VTEC actually delivers less torque (i,e. less power) than the i-DSI, consistently 0.2kgm across the relevant rpm range. After 3,000rpm, the advantage offered by the VTEC mechanism really comes into the picture and while the torque of the i-DSI engine is now dropping steadily, the torque of the VTEC engine continues to rise, finally peaking at 14.6kgm at a high 4,800rpm, 1.2kgm more than the i-DSI. The redline of the
two engines are slightly different as well, the L15A i-DSI redlining at 6000rpm while the new L15A VTEC redlines at 6,300rpm. This difference between the 2 engines' power characteristic can in fact be quite easily felt when 'dragging' in 7-speed mode, the VTEC being very revvy in the higher rpms. While the i-DSI engine strains to rev up beyond 4000 - 4500rpm, the VTEC charges steadily onwards to the 6300rpm redline and with plenty of aural entertainment. The engine note of the i-DSI is already surprisingly sporty but the VTEC brings the aural quality up one notch higher.

For Malaysia, the City VTEC comes only with the excellent CVT-7 gearbox. This is mechanically identical to the one used on the City i-DSI but operates differently, controlled via the ECU, to exploit the characteristics of the VTEC engine and also to offer a more 'sporty' drive. This 'more sporty' drive is via a change in the operational characteristic of the gearbox in response to throttle input - i.e. a faster ramp up of engine rpm for the same throttle input with the result the car has higher pick-up for the same amount of pressure on the throttle. The engine now revs higher for the same throttle position and the engine sounds more rowdy (better relatively) and the idea is that for a (small) 'sporty sedan', one does not mind the more rowdy engine when one is indulging in some 'spirited' driving. 7speed mode is also available with the gearbox of course as is the steermatic steering wheel mounted shifters. The ratios for the 7 gears are identical between the i-DSI and VTEC versions.

To cater for the more powerful engine and also the fact that the City 1.5l VTEC is now set-up as a 'sporty sedan', the suspension has been also tuned accordingly for more 'sporty' handling. The parts changed are the front damper, the rear spring and damper, and the rear stabilizer (anti-roll bar). The weight difference between the L15A i-DSI and L15A VTEC engines are similar enough that there is no drastic change in weight distribution on the car so the changes are all for delivering a better handling performance.

The EPS is also said to have been re-tuned for 'more sporty' response. The steering ratio and the number of turns lock-to-lock is the same between the i-DSI and VTEC however, so the re-tuning is most probably for steering 'weight' or how heavy the steering feels. This is probably following some feedback received by owners of the i-DSI City over the light feel of the EPS but a re-tuning is also needed because the wheels for the City VTEC has upped to 15", the City VTEC using 185/55/R15 Goodyear Eagle NCT-5tyres on 15 X 6.0 JJ spec sport rims. Another important change for the City VTEC would be the use of disc for both front and rear brakes. The front is the standard ventilated disc while the rears for the City VTEC is now using solid discs.

Of the rest of the car, the most notable would be the availability of a rear trunk spoiler for the City, a long overdue accessory really. The front grille is also slightly different. It is still the same basic design but is now more 'open' as shown on the photo. This will allow more air-flow into the engine bay. There are also other minor changes to various parts of the car, cosmetics as well as fittings (like an MP3 capable head unit for the audio system of the City VTEC), their primary target to fine-tune the City, both i-DSI and VTEC variants into an overall more complete car.

Honda City VTEC : Burning Questions by the Enthusiasts

The original City i-DSI was a run-away success from Honda's point of view. Even here in Malaysia alone, over 10,000 units were sold by the time the City VTEC was launched. So there were certainly a lot of attention on the new VTEC variant when it was launched, especially from current owners of the i-DSI as a number of them have been wishing for a bit more power than just 88ps from the L15A i-DSI. As a result, there were quite a number of discussions about whether it was possible for an enthusiast to build an L15A VTEC from the L15A i-DSI on the original City i-DSI. It is with this in mind that I asked a few rather 'pointed' questions to the Honda R&D engineers during the technical Q&A session at Bukit Tinggi. A few who were present in the session even had a good laugh at the strangeness of my questions but luckily the important people concerned, the Honda R&D engineers and most of the Honda Malaysia staff understood the background to asking the questions and that I had to ask them as a enthusiast. Here then are roughly the 4 questions that I asked. The responses are a combination of excerpts of answers from the Honda R&D engineer and additional infor of my own which are listed within brackets.

Q : Is the main difference between the L15A i-DSI and the L15A VTEC engines just in the cylinder head ? Can I just drop an L15A VTEC cylinder head on the L15A i-DSI, and with a suitable change of ECU, build myself a home-made L15A VTEC engine ?

R : There are quite a bit more differences between the L15A i-DSI and the L15A VTEC than just the cylinder head (I think the pistons are different as well). As to whether one can build a home-made L15A VTEC engine from the L15A i-DSI, it is of course technically possible but it would not be too practical as almost all components of the engine would have to be changed : head, intake, exhaust, wiring harness, etc. It will be a very elaborate project and you will more or less end up with a engine which has almost everything changed.

Q : What is the power handling limit of the CVT-7 gearbox ? I.e. how much extra power can I squeeze out of the L15A engine (e.g. NOS, turbo) without worry about the CVT-7 gearbox breaking, especially the much talked danger of the CVT steel belt snapping ?

R : The Honda R&D engineers do not know the value. They have not yet had a case where the CVT metal belt broke before and note that the CVT-7 gearbox first existed as the Multimatic gearbox in Japan way back in 1995, 9 years ago. (Also, the CVT-7 is being used on the JDM Honda Odyssey which uses the 2.4l K24A DOHC i-VTEC engine delivering 160ps and a lot of torque. So the power handling limit of the CVT-7 gearbox is quite high really. But note that the Odyssey's CVT-7 gearbox is fitted with a torque-converter, most probably for better take-off from standstill. Also, don't forget there are manual gearboxes for the City, available in Thailand versions.)

Q : How many ECUs are there ? One for engine and one for CVT-7 or 1 for both

R : There is only 1 ECU which controls both the ECU and the CVT-7 gearbox.

Q : Can the rear disc brakes be simply taken from the City VTEC and bolted on to the City i-DSI ?

R : No they can't. The rear axle beam also needs to be changed and the head R&D engineers can't confirm but he thinks additional components of the rear suspension might need to be changed as well. (In respect to this, one Honda dealer whom I know well, WEGRO HONDA, told me they actually tried to bolt just the rear disc assembly from the City VTEC onto the City i-DSI and they found that it won't fit.)

These then are very briefly the 4 questions that caused quite a bit of stir at the Q&A session. While some present at the session did not understand why such questions had to be asked, I think readers of this article, who are true enthusiasts, would readily agree that they are most relevent questions. I also spent quite a bit of time with the Honda R&D engineers during the 'free and easy' periods, where the atmosphere was much more informal and relaxed. I was basically digging for infor on what I can do to my own Jazz 1.5VTEC of course and many R&D engineers I have met are car buffs themselves. We also discussed a bit on the questions I asked during the Q&A in those informal chats. In the end, my opinion and suggestion to City fans would be that if one already has a City i-DSI, that it is not practical to fuss over the engine eventhough the 22ps extra power is quite significant. For the trouble and expense of trying to build an L15A VTEC out of a L15A i-DSI, other things can be done that will be more cost effective. Similarly too for the rear disc brakes. The suspension items are quite interchangeable though and one can add them for an nice upgrade in handling. So, my recommendation would be for City i-DSI owners to enjoy their car as it is and to look for the tried and trusted routes to modifying for more performance instead of trying to build a VTEC L15A. For those who are considering a purchase of the City however, choose the City VTEC if you are a performance and handling buff but if you're a more casual driver, the City i-DSI would still give plenty of go with fantastic fuel economy as well. It might be seen as a canned recommendation but really for potential buyers in this market segment, one cannot go wrong with either variant as long as one takes careful steps to understand one's own requirements and expectations in the selection process.

With the technical details taken care of, now is the time to cover my impressions from the test-drive.

Honda City VTEC Test-Drive

For the media session, Honda Malaysia had us starting from the Hyatt Saujana hotel at Subang, taking a mainly highway/expressway route through the NKVE and part of the middle ring road and then getting on to the East-West 'Karak' highway to head for the hill-top resort of Bukit Tinggi. The idea is to show-case the highway cruising ability of the new and more powerful City VTEC and the drive up the winding twisty road to the hill-top of Bukit Tinggi will also give us a chance to test the handling of the car as well as sample the more powerful engine and 'sporty'-tuned CVT gearbox. For this session, I was again happy to find that they have paired me with my friend YS. The 2 of us were to share a City VTEC, each driving part of the way, flagging off from Hyatt and all the way to the Bukit Tinggi resort.

YS and I agreed to break the journey into 4 parts, 2 highway and 2 twisty roads so that both of us will be able to sample the City VTEC over both highway and twisty roads. I took the wheels first and we left the Hyatt hotel and made our way straight to the NKVE expressway toll entrance nearby. Halfway to the East-West highway though, YS' eyes lit up and he told me that nearby is a nice country back road, twisty but relatively lightly used, where he used to race back in his rally days. He then asked if I mind deviating from the route Honda gave us for a 'more interesting' alternate route. What would you think my answer was ? And so we exited the middle ring road and entered a village area. It was quite a while actually before we finally got onto the deserted part of the country road. It was a great route.

In this stretch of road, I tried all four gearbox modes : D, S, 7speed and 7speed with manual shifting. In this low to medium speed, twisty environment, the best results - best speed and enjoyment - comes from 7speed mode with manual shifting. Traffic was pratically non existent and for most part, visibility of the road up ahead - and of incoming traffic was excellent. As a result I could take 'racing lines' whenever I wished to - cutting out to the opposite side of the road and then cutting across the apex of a tight corner and back out out to the opposite side again before finally swerving back into my own side of the road. 7speed manual mode allowed me to downshift into the correct gear as I enter the corners. Inside the corner, the gearbox won't shift gears if it is in 7speed manual mode so I could modulate the throttle for optimum cornering speed. On the exit, the gearbox automatically upshifts when I rev until the engine red-line so it turned out to be a nice convenience feature. I was consistently impressed by the poise of the City VTEC when taking tight corners at quite high speeds. For the corners where I stuck to my own lane throughout, I would brake early to ensure a slow entry speed (and mainly because I am not familiar with the roads). Then I could and would accelerate steadily out of the corners with relatively little sideways roll from the car. Being unfamiliar with the roads, I did not push the car hard enough to elicit much more than a muted squeal from the tyres in the corners. Then all too fast it was time to pass the car over to YS. I really didn't have my fill of fun yet but I suspected that YS was all ready to go a bit beserk since I could sense he was quite ready to relive his younger days doing professional rally-racing. Furthermore he is very familiar with the route. So I eagerly got into the front passenger seat for the 2nd part of the 'rally approved' detour of the test-drive.

As I had suspected, YS did 'relive' his youth as a rally racer and he really let loose, power sliding the City VTEC through most corners. To induce the 'over-steer', YS used extended trail braking. What he did was to 'break the tail loose', i.e. force the rear tyres to lose traction before the front tyres. This is done by braking late and then steering the car into the corner while still braking hard. The weight transfer to the front wheels would lighten up the rear of the car, unloading the rear tyres enough so that it breaks traction and the tail would break loose and 'swing around'. Now a quick twist of the steering wheel to counter steer and simultaneously planting the right foot to rev up the engine, it was then possible to 'power slide' the City VTEC with the tail out and slight sideways around the corner, ala Initial-D style ! Personally I would be honest that while I do this at the Sepang track, I certainly didn't have the guts to do it with the City VTEC on the country road. But it's not because I don't trust the City VTEC but because I am not familar with the roads and I don't want to have to divide my attention between both learning about the City VTEC's handling limit and the road conditions at the same time. So it was a nice piece of fortune that YS knows the roads very well and was 'in the mood' for such fun during that detour. We took the turns at relatively high speeds - at times touching or even exceeding 100kph. To its credit, the City VTEC never felt like it was losing control even at the limits with its tyres screaming wildly around the tight corners. There was never an occasion where YS had to compensate or correct the steering when we straighten out after the corner exit.

Eventually the fun ended when we exited the country roads and merge back into the main roads to get back onto the East-West highway. After paying the toll (have I ever mentioned in my articles that Malaysia probably has the highest ratio of toll-gates to roads in the world ?! :) ), it was broad sweeping corners mostly uphill but some downhill as well, YS seems to be interested in the top-speed of the City VTEC, most probably because he just had the Jazz 1.5VTEC for loan and so he wanted to compare the two. I remember we were just shy of the 190kph during this 'test' but I must highlight that the engine has barely exceeded the 1,000 km mileage and so is not really properly run-in yet for max performance.

Next was the uphill stretch to get from the bottom to the top of the hills of Bukit Tinggi where the Colmar Tropicale French-themed resort is located. This access road is very twisty and there is also the danger of actually rolling off the road and down the side of the hill if one loses control. Both YS and I were eagerly waiting to test the City VTEC's performance in this section of the test route as it introduces the uphill element and so will put a premium on good engine power, or more specifically a wide power band characteristic. Both of us are quite a bit more restrained now. We both felt similarly that there's nothing to prove in test-drives and while we have a responsibility to check the performance of a car as accurately as we can, nothing is acheived if we get over enthusiastic and roll over and down the hill as a result. So this time even YS did not power slide into the corner. Both of us took racing lines when the road was clear or more usually simply kept to our side of the road and corner at the limit of what we felt the City VTEC was capable of. For the uphill climb, I have to say I found the 7speed mode to be not optimum. The ratios between 2nd and 3rd gears seemed to feel very different in terms of pulling power - downshift into 2nd and the car screams up the hill but once into 3rd gear, the engine seems to strain to gain rpm and speed. So sometimes when I thought I would try to use a higher gear into a corner fhe City VTEC would strain and I would end up with last minute downshifts. The placement of the shifters on the steering wheel makes it sometimes inconvenient too. Eventually I end up simply running the car in 'S' mode. Somehow the re-tuning of the CVT-7 gearbox for the VTEC engine is quite appropriate for the drive up Bukit Tinggi as the engine revs were quite nicely placed around the 4000rpm region when I was charging around the corners and the more immediate throttle response made it possible to power out of the corners. Again it seems too soon and suddenly we found ourselves up at the hill-top. As an indication of the amount of fun we had, we were the first car out of Hyatt and eventhough we took the detour and had to dilly our way for a few kilometers over village roads, we still ended up being the second car to arrive at the hill-top resort !

Honda City VTEC : Conclusions

I had a lot of fun driving the new City VTEC up to Bukit Tinggi during the media session. So my impressions are extremely positive about this new variant - it really is a preppy small sports-sedan. Used with sensible common-sense, it can be a very fast means of getting around in all sorts of roads and conditions including high-speed cruising. And for an auto, thanks especially to the 7speed mode, it was a lot of fun to drive especially on tight twisty roads ! Just keep a good perspective of its performance abilities in relation to its market segment and the City VTEC will deliver plenty of driving enjoyment. In the end, I think the only disadvantage of the new City VTEC is that it appeared just a bit too late on the market. At the moment, eventhough sales are pretty good, Honda Malaysia's original hope that it will help the City exceed the sales of the Toyota Vios are not acheived. This apparently is the same situation even in Thailand where it was originally designed and first released. Indeed I was told by a Honda staff that there was even an admission over there that it was a wrong marketing move to introduce the City i-DSI first, i.e. with retrospect, it would well be much better to first launch the City VTEC and to follow with the i-DSI variant as a more specialized fuel-miser variant. Nevertheless what has been done is done and I can only hope that Honda has learnt its lesson and will remember it well for the future.

Because the media session takes us up to Bukit Tinggi, even though I had my GTECH PRO with me, there was just nowhere suitable for any standing start acceleration tests. So no such infor is available in this preview. At the moment, I am patiently waiting for the mainstream press and media to finish taking the car for test-drive and hopefully for the mileage to accumulate to a favourable figure. I did just this with the Jazz 1.5VTEC for which I recently completed the full suite of performance tests. It has just over 10,000km mileage accumulated and it was a huge pleasure to drive and delivered plenty of great surprises in the tests. Consequently, I think this new approach I am adopting will be the best and most appropriate to allow the cars to show their best potential : a report of the technical details and a quick impression from the media test-drive session, followed by a possibly extended period to wait for the test cars to accumulate hopefully 10,000km mileage before taking one out for a complete test. Actually for the City VTEC, it should not be that far away so stay tuned for the full performance test of this car from us in the near future.

Wong KN
October 2004
© Temple of VTEC Asia