VTEC Tuning – How to make your VTEC engine go even quicker

When it comes to screaming high RPM performance engines, one name instantly spring to mind: VTEC. In addition, this issue we’re going to show you how to make them even quicker...

1989 was a special year for the Fast Car world. That’s when Honda re-wrote the rulebooks with the release of the B16A VTEC engine, pushing out around 160bhp from a high revving 1.6ltr non-turbo engine back when most other N/A 1.6s were struggling to top 110bhp. From then on, the term VTEC and big revs have become the norm for sporty Hondas, and while tuning them took a while to seriously take off in the UK, these days the Honda VTEC lumps are some of the best 4cyl engines to upgrade. In addition, we’re here to show you how...

What is VTEC anyhow? In addition, why is it so good? VTEC is Honda’s name for a variable valve timing and lift system, and while quite a few other manufacturers, from Fiat to Porsche, all use similar systems, Honda’s version is by far the most famous, and arguably the best.

Variable valve timing and lift is exactly what it says. It varies when and how far the valves open, and in fact it adjusts how long they’re open too. It effectively gives you two different sets of cam profiles fitted to your car at once.

So why is this good? Well some people think VTEC is what creates power, but that’s not strictly true, the same wild cam profile without VTEC would create the same peak power number. What VTEC actually does is give you a mild cam profile that drives nice at lower RPM, and then it switches to the crazy cam profile that gives you the big high RPM power. Either without VTEC, you’d have the mild cam profile with the nice low RPM driveability but wouldn’t make big power, or you’d have the crazy cams, which give good power but would drive like crap under around 5000rpm. VTEC gives you the best of both worlds.

B16/18 The original VTEC motor that started the craze, the VTEC B-Series engines were originally found in 1.6ltr form in CRXs, Civic VTis, and of course in the original Civic Type-R, where it produced a pretty bonkers 185bhp while revving to 9,000rpm. It’s also available in 1.8ltr, where it’s mostly found in five-door versions of the Civic VTi, and in it’s most powerful form in the original Integra Type-R. From a tuning point of view, it’s fair to say all of these engines have huge potential, and as sub 2ltr engines they’re still hard to beat.

Naturally aspirated

While there are extreme naturally aspirated B-Series engines stroked to over 2.3ltr, revving to well over 10,000rpm and making 350bhp, these are serious money drag-only setups running on methanol. However, if you want it, it’s possible!

In naturally aspirated form, while mild gains can be had from simple bolt-on mods and cam swaps, it’s a lot of work even getting the B16A 1.6ltr even up to standard B16B Civic Type-R power. Therefore, unless you’re determined to spend many, many thousands just to see barely over 200bhp, the key to naturally aspirated power is increased capacity.

The 1.8ltr block is your instant capacity boost, and there are stroker kits. Even the B20 block from Honda CRVs to allow you to go bigger, and we’ve seen stroked B-Series lumps breathing through four big throttle bodies making over 260bhp even on pump fuel with decent driveability, though these days these builds are getting rare, as most head for forced induction or a K-series engine swap.

Supercharged

Supercharging the B-Series is far from common, but kits exist, and the proven gains are very impressive. Enough to make you wonder why you’d want to stay naturally aspirated anyhow! There’s two basic types of supercharger, positive displacement and centrifugal, and both options are possible on a B-Series.

Starting with the positive displacement charger, Jackson Racing was the main suppliers of the B-Series supercharger kit. Though we say were, because it’s no longer in production. A standard B16A with this kit has been known to make 230bhp+ at just 11psi, pulling all the way to over 8,500rpm with no let up, and the bigger B-Series engines make even more. The Integra Type-R lump is making closer to 300bhp at the same boost.

The other option is using a centrifugal supercharger, which doesn’t make as much low down torque as a positive displacement charger, but tends to make more power. Kraftwerks produce a kit using the popular Rotrex supercharger that’s proven to practically double the power of a 160bhp B18 at just 9psi, and up to around 350bhp with a few more mods. Beyond that level, supercharging a B-Series is rare as most people go turbo for big power, but a supercharged B-Series can go 600bhp. It just needs someone to do it.

Turbo

By far the most popular power upgrade for the B-Series, there’s no end of turbo conversion parts for these engines, ranging from mild to wild, from super-low budget to wild big-buck stuff. In addition, no matter what you use, the results are always great for the money spent.

People have achieved over 500bhp from stock internal B-Series engines, which is incredible considering the capacity. However, generally around 350bhp is considered long term reliable, and even that makes a seriously fast car at a low cost. Aside from the peak power figure, turbo gives massive mid-range torque versus the naturally aspirated engine.

With forged internals, up to around 450bhp is considered reliable on the standard block, but at this level you’re on the limit of the stock cylinder sleeves, so while it’s in pieces it’s common to go to aftermarket sleeves too. How much power is possible from a B-Series? Well the Speed Factory Civic has hit 203mph in the quarter-mile with a turbo B-Series, and even a McLaren P1 only hits 152mph. It’s quite a lot, around 1850bhp in fact.

Nitrous

Thanks to the US drag racing scene, there’s been quite a lot of development with nitrous on the B-Series, and while it’s not in the same power league as turbo cars, it can easily make a mild N/A road car in to a genuine 10sec quarter-mile weapon.

At a more basic level, people have had no problems with a simple 75bhp setup, and there are people running as much as 150bhp on standard internals with no problem on well setup nitrous installs – almost doubling the standard engine power!

For people getting serious, just like all the previous setups, it’s time to forge the internals to be able to take a big hit of nitrous. With forged internals and other supporting mods there’s a number of B-Series out there, while they might make ‘only’ 190bhp in naturally aspirated form, make well over 450bhp with their nitrous activated – often using sophisticated, direct port, multi-stage, ECU controlled setups, more commonly seen on big V8s.

“VTEC Killer” setups

On the face of things, it sounds an odd thing to do, but deleting VTEC is actually a thing, albeit rare. It’s mostly found, for various reasons, on race engines and tuned lesser power VTEC engines. Due to the fact, it deletes the mild cam profile, effectively putting the car in the VTEC zone right from idle; it isn’t great for low down power and driveability. However, it certainly exists and has its uses.

The technical bonuses of this is it allows some of the VTEC components to be removed, reducing valve train mass for better response and reliability, and it helps keep the oil pressure stable too, as VTEC relies on oil pressure for control. On K-Series engines especially, along with a cam swap, it allows some of the more economy orientated versions to produce similar peak power to the Type-R lumps too.

It also sounds crazy at idle. Which is a nice plus point for most of us.

K20 ‘Type-R’ engine

While there are quite a few variations of the Honda K-Series engine, all very tunable, we’re concentrating on the 197bhp+ models found in EP and FN Civics, and DC5 Integras. What we will say though, is the 160bhp versions found in various cars such as the EP Civic Type-S, while certainly not as good as the Type-R lump, and are still very tunable if you don’t mind getting your hands oily. However, that’s a completely different story...

Naturally aspirated

While basic bolt-ons do give small power increases, just like a B-Series, don’t expect giant jumps in power from the typical first steps of an exhaust, intake and remap. However, if you combine the aforementioned things with a good exhaust manifold and cams, people have made around 250bhp – beyond these things start to get much more serious. While over 300bhp is possible with a full race K20, capacity is king, and that usually means the 2.4ltr K24 block, giving easy power and torque increases.

Relatively mild K24 setups with a single throttle can make over 300bhp, which is both seriously impressive and damn fast. No wonder they’re so popular. Going beyond this, there’s stroker kits available to make the K24 even bigger, and around 400bhp on pump fuel has been achieved on serious K24 N/A builds – closer to 500bhp on wild methanol-fueled drag engines!

Supercharged

While turbocharging is rapidly taking over popularity, supercharging has always been hugely popular on the K-Series, especially the Jackson Racing and TTS kits, though there are other brands out there too. The JR kit is probably the best known, and while it’s simple enough to be fitted in a day, it’s proven to add over 100bhp more to the standard engine with great long-term reliability. Being a positive displacement charger means the car drives like a much bigger engine, with big power increases from idle right up to the rev limiter, and it makes the car much easier to drive fast.

TTS supercharger setups all use Rotrex centrifugal superchargers, so while it doesn’t give as much low down power, top end power is incredible. It is well over 400bhp on standard internals, and over 500bhp on a built engine!

Turbo

As ever, turbo is king for peak power, and people have seen over 500bhp on standard internals on Type-R engines, but the limit is actually torque. Above around 300lb/ft. of torque you’re beyond the safe limit of the standard conrods, so while you could easily go beyond this limit even with a 300bhp engine if you like, with careful boost control to limit torque people have reliable engines even at well over 400bhp.

Beyond this level, uprated controds and valve springs are necessary, and because of that, most go for a fully forged build. From then on, you can go as far as you dare, to 1,100bhp and beyond...

Nitrous

As with the B-Series, the K20s use in drag racing in the USA is what we have to thank for nitrous developments on the engine, and while it’s not a common thing to do, the gains are impressive. Just like with turbocharging and supercharging, people have achieved over 300bhp on standard internals with nitrous. Once again, rods especially are what limit things. In addition, while it’s rare for people to build forged K-Series for dedicated nitrous use, there are K24 powered drag cars in the USA with that exact setup delivering 500bhp+.

Hondata ECUs

One of the big advantage of tuning Hondas is the fact ECU tuning is just so easy, thanks to Hondata ECUs. Hondata is a range of aftermarket programmable ECUs for Hondas which not only are incredibly easy to install and set up. However, they’re pretty low priced, hugely capable, and perhaps most importantly, there’s a ridiculous amount of knowledge and help out there available for them.

Aftermarket ECUs are often tricky to install and get running, to say the least. However, this couldn’t be easier, and of the many cool things about VTEC tuning, we think Hondata is one of the most useful aspects.

F20/22C

Found only in the Honda S2000, this engine is, like all Honda VTEC lumps, a seriously high revving motor that can be tuned to quite ridiculous levels of power. Available in 2ltr and later 2.2ltr form, and producing up to 240bhp while revving to an insane 9,200rpm in the original JDM version, it’s a serious bit of kit even from the factory. It’s worth noting, while it’s distantly related to other earlier F-Series engines, it’s got very little in common, and is actually closer in general spec to the K-Series engine.

Naturally aspirated

Being one of the most highly tuned naturally aspirated engines ever to be fitted to a production car, you’d think there are no more gains to be had. However, amazingly there are worthwhile gains from even basic bolt-on upgrades. A good full performance exhaust system and a well-tuned ECU to match have been known to add around 20bhp and very noticeable increases in midrange torque – something the engines are sorely lacking as standard. Going further than that, some people with ITB quad throttle conversions are seeing around 40bhp more than they made on the standard engine, and others a good chunk more again with uprated cams added to the mix. If you wish to go further, there’s countless parts available, including stroker kits that can take it right out to 2.5ltr. Many people are seeing well over 300bhp naturally aspirated with their road car engines, and around 400bhp on hard-tuned race lumps.

Supercharged

Centrifugal supercharger kits have always been very popular for the F20/22C engine, and their high RPM power delivery suits the revvy engine perfectly. Kits from Vortech, Comptech, HKS, and others have all been produced over the years, but by far the most effective are the ones by UK tuners TTS Performance. Using Rotrex superchargers, these kits give anything up to 600bhp without losing any of the original S2000 engine feel – just much, much faster everywhere in the RPM range.

Positive displacement superchargers on the other hand are incredibly rare, and while there’s various reasons for this, the few we have seen are very impressive indeed, not only giving over 400bhp, but over 200lb/ft. of torque even at just 2,000rpm. About double what the standard engine is doing by then.

Turbo

One thing about the F20/22 is it is STRONG, to the extent it’s not common for people with turbocharged ones to bother uprating the internals until well over 700bhp. The standard internals record is well over 800bhp! While plenty of them blow up, it’s usually down to tuner error rather than finding the true weak point of the internals. In addition, because of this there’s plenty of 500bhp+ ones about with genuine long-term reliability with standard internals.

However, what if you wanted to go really, really stupid? Well, while there’s plenty of companies about supplying turbo conversion parts for these cars, and Full-Race do a kit that sits the turbo quite far forward under the bonnet, allowing for REALLY big turbos to be fitted. So what’s the limit? Well there’s fully built S2000 lumps with turbos pushing out over 1,200bhp. The most difficult thing is finding a transmission that can handle this insane amount of power.

Nitrous

While there’s no reason the F20/22C shouldn’t be as capable with nitrous as any other Honda VTEC lump, it’s very rare to see one with nitrous. We’ve seen cars with basic 75 shot systems and even 125bhp setups controlled by the ECU while still on standard internals with no problem, and we’ve no doubt fully built engines can handle many hundreds of bhp worth of nitrous. Overall, it’s just not a popular way for the S2000 lumps.

Other cool VTEC lumps

We can’t cover every decent Honda VTEC in this feature, as they’ve made so many. However, here’s a few more well worth a mention...

H22A

These 2.2ltr 16V VTEC lumps are very, very good, and were the engines Honda chose to base their Formula 3 race engines on, not to mention their BTCC and JTCC Touring Car racers. Proven to produce well over 300bhp with heavy N/A tuning, 700bhp+ with basic forged internals and turbocharged, and well over 1000 when really pushed hard, these engines are very strong and capable.

C30/32A

This is the V6 engine from the original NSX and the second ever Honda car engine to have VTEC. While being fitted to an expensive and rare supercar means they’re not the most common engine to tune, they certainly can be, with tuned naturally aspirated versions making as much as 500bhp and turbo ones make over 450bhp on standard internals and fully built ones pushing out well over 700bhp. Is there such a thing as a bad Honda VTEC engine? Well, no, not really!

K20C1

This is the 2ltr Turbo engine found in the latest incarnations of the Civic Type-R, and while it’s technically a K20 engine, it’s actually quite different. Aside from the obvious fact it’s turbocharged, it also features direct fuel injection and has no real exhaust manifold. The turbo bolts directly to the single large exhaust outlet on the head! While it’s still very new, there’s already upgrades available, a simple remap pushes them to around 350bhp, Forge Motorsport intercoolers giving another 10bhp on a standard engine and no doubt more with a remap, and various manufacturers already making performance exhausts. Is this the future of VTEC tuning? We think so.

Z30A

This is, allegedly, the designation for the engine in the new NSX, a 3.5ltr twin turbo engine pushing out 500bhp – not including the extra 75bhp from the electric motor! While it’s too new to have any tuning available yet, it’s only a matter of time, and US-based Hennessey Performance are already developing a lot of tuning goodies for them, including bigger turbos!

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