Modding tuning and best performance upgrades on the Honda H22 engine!

Modifying and improving: "H22 Modifications"

H22 Modifications Guide

How to modify and upgrade the Honda H22

"Comprehensive guide to tuning the Honda H22 engine!"

Popular tuning sites like TorqueCars often are seeing threads requesting info on how to improve the H22 from people wanting to know what are the ultimate H22 mods that work. So let us look into Honda H22 parts and outline the best modifications on this great engine and point out some common pitfalls along the way.

The Honda H22 are fantastic to work on and with the ultimate uprated parts like ECU maps, turbo kits and camshafts you will noticeably increase your driving pleasure.

In this article we look at H22 tuning and show the best modifications.

When talking about the optimum parts for your H22 engine, we are going to concentrate on the modifications that give the best power gain for you money.

H22 induction kits

Improving air intake on the H22

You need air and fuel for an engine to work. If there is too little fuel then it will run lean, if there is insufficient air it runs rich losing power . We'll pick up on fuelling later in this article but for now we shall look at air supply.

So the aim to any engine modification task to push air and fuel into the H22 engine but this has a knock on effect with the air flow sensor.

It is common that there's a restriction in the air flow sensor (AFM/MAF/MAP) on the H22 when considerably more air is being sucked into the engine.

When tuning you may well find you need to get an air sensor or flow meter capable of upto 4 bars to cope with quite large power gains, whereas the OEM air sensor limited bhp and torque at a much lower level.

Engine intake manifolds take the air from the filter and allow it to be sucked into the engine cylinders with fuel for the squish phase.

The shape and rate of flow of the Air Intake manifolds can make a large change to fuel atomisation on the H22.

Commonly we find the air intake manifolds are crying out for motorsport parts, although some manufacturers provide fairly well optimized air intake manifolds.

Fitting big valve kits, doing a bit of port matching and head flowing will also boost bhp and torque, and importantly will raise potential for a better bhp and torque increase on other mods.

H22 performance cam tips.

Each engine responds better to more aggressive cam durations check your engine on a rolling road.

The ECU mapping and fuelling also have a large bearing on the torque gains you'll hit.

Altering valve durations can alter the torque band and on most engines the exhaust and intake durations do not need to match, although most cams and tuners use matched pairs there are some advantages to extending the intake or exhaust durations.

The camshaft profile plays a big part in the engines power output so camshaft upgrades make quite a large difference. The intake & exhaust durations will alter depending on the chosen camshaft profile, so large engines power gains are on offer for camshaft upgrades.

NB: Fast road camshafts commonly raise the bhp throughout the rev band, you may lose a little low down torque but top end will be better.

Motorsport and race camshafts, raise the top end band but as a result the car will not idle smoothly and low end power nearly always suffers.

For a car driven daily you need to match your bhp range to your typical driving style.

I'd be amazed if you have ever thought a H22 Motorsport cam is a pleasure to live with when on the daily commute.

Stage 1, 2 and 3 mods for the H22

Before we break the best tuning upgrades down into stages of tune, let's list the most effective tuning upgrades for you.

  1. Suspension Upgrades - always improve your cars handling
  2. Brake Upgrades - Even before adding power improve those brakes
  3. Intake - make sure the intake is not restricted, use filters and intake upgrades to improve this
  4. Exhaust - as with 3 ensure there is not restriction in the exhaust, cats are the usual bottleneck
  5. Tunes - remapping, piggyback ECU's and aftermarket ECU's can all make decent gains
  6. Fuelling - when you've increased power you'll need to match this with more fuel
  7. Turbo upgrades - Improving the intake with a large turbo and better flowing intercooler will be the biggest power gain you'll see (but one of the most complex).

This video guide to tuning cars is a great starting point to work from in your project.

Stage 1 H22 parts:

Drilled & smoothed airbox, Sports exhaust manifold, Fast road camshaft, Remaps/piggy back ECU, Panel air filters, Intake headers.

Stage 2 H22 parts:

Fast road cam, Sports catalyst & performance exhaust, high flow fuel injectors, induction kit, fuel pump upgrades, Ported and polished head.

Tuning tips and articles Engine tuning Transmission tuning Care care Intake & exhaust mods Improve handling Forums

Stage 3 H22 parts:

Crank and Piston upgrades to alter compression, Engine balancing & blueprinting, Twin charging conversions, Adding or Upgrading forced induction (turbo/supercharger), Competition cam, Internal engine upgrades (head flowing porting/bigger valves).

Carefully think through your options and then find your mods and set yourself a power target to save yourself from expensive mistakes.

ECU mapping helps unlock the full potential of all the upgrades you've done to your H22.

You will typically expect to see gains of approximately 20-30% more power on turbocharged vehicles and you can expect to see around 15% on NASP engines, but the outcome usually depend much on the upgrades you've done and the condition of your engine.

Turbo modifications on the H22

To get a turbo working on a NASP engine there is a lot involved, from lowering compression ratio to improved fuel supply and mapping, so we have found a great guide to helpavoid the common pitfalls or end up with an unfinished project because you were not told what you were getting into by doing this on the H22.

The more air you can get into an engine, the more fuel it can burn and uprating the induction with a turbocharger upgrade makes major power gains.

When your car has a turbocharger parts are relatively easy and you will discover turbo charged engines already contain many forged and stronger components.

However you will find an engines will have power limits

See where you'll find these limits and install higher quality crank and pistons to cope with the power.

It's not unheard of people spending a lot of money on turbo charger upgrades on the H22 only to experience the whole thing explode on it's first outing after it's used on the roads.

Larger capacity turbos commonly suffer low end lag, and small turbos spool up really quickly but do not have the peak end power band gains.

Over the last 20 years the world of turbo chargers is always moving on and we now see variable vane turbo chargers, where the vane angle is altered according to speed to lower lag and increase top end torque.

Twin scroll turbo chargers divert the exhaust gases into 2 channels and push these at differently profiled vanes in the turbo charger. They also help the scavenging effect of the engine.

Beefing up the air intake by adding a supercharger or additional turbo will help you achieve very large bhp gains, although more difficult to configure. We have this article on twincharging if you want to read more.

Tips about fuel supply on the H22

When you boost the power you will need to uprate to the fuel delivery.

More power needs more fuel. Don't forget to be generous with your flow rate on the injectors.

As a rule of thumb add 15% to the flow rate when fitting an injector, helps cope with injector deterioration and affords you some spare capacity should the engine need more fuel.

Don't forget that different fuel grades will usually require different settings, a high octane fuel will burn more efficiently than lower octane fuel for example. A car will trim fuel supply to keep within the ideal air fuel mix but at the extreme ends you may need to adjust your injector capacity, or the mapping or you'll get flat spots and potential lean or rich fuel issues..

Recommended H22 performance exhaust upgrades

You only need to to boost your exhaust system with an upgraded one is if the existing exhaust is creating a restriction in flow.

On most factory exhausts you should find that your flow rate is still fine even on modest power gains, but on a serious tuning project with a big boost in power you will certainly need to get a better flowing exhaust.

Note that with the widest exhaust you can find you'll reduce the exhaust flow rate - the best exhausts for power gains are usually between one and a half to two and half inches. Your exhaust design, the bend angles and construction are what have more effect on flow rates than your pipe width to a certain extent. So the exhaust design is a big factor.

The usual suspects causing problems in your exhaust flow rate can be located the catalyst installed, so adding a higher flowing sports alternative will help avoid this restriction.

Catalyst removal (NB:catalysts reduce harmful engine emissions) is illegal in most countries and regions.

Faults issues and things to look out for on the H22

Like most engines an H22, should have few issues if it gets properly serviced and looked after.

We cannot stress enough the need for oil changes with the correct grade of oil on the H22, failure to do this will exacerbate engine wear, on a tuned H22 this is more important than ever and close attention should be paid to your maintenance schedule.

If you are interested in learning more or getting impartial tuning advice for your H22 why not pop over to the forums at TorqueCars where you can chat about H22 tuning options and read about others projects who may be planning to do similar modifications on their H22.

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