Modding uprating the AlfaRomeo Alfa JTS engine!

Modifying and improving: "Alfa JTS Modifications"

Alfa JTS Modifications Guide

How to modify and upgrade the AlfaRomeo Alfa JTS

"Comprehensive guide to tuning the AlfaRomeo Alfa JTS engine!"

TorqueCars are always getting posts asking about how to improve the Alfa JTS from people wanting to know what are the ultimate Alfa JTS modifications. So let us look into AlfaRomeo Alfa JTS parts and outline the best modifications on this great engine and point out some common pitfalls along the way.

The AlfaRomeo Alfa JTS are fantastic to work on and with the ultimate performance upgrades like ECU maps, turbo upgrades and camshafts you will maximize your driving pleasure.

In this article we examine Alfa JTS tuning and report on the greatest modifications for your car.

Just because particular tuning mods are are common on Alfa JTS it doesn't mean you should fit it, instead we'll concentrate on the best tuning mods that will give your Alfa JTS the biggest power gain return for your cash.

Without us subscribing to the mentality of 'if it's shiny and makes more noise it must be good' you seem to get in many tuning magazines and on car forums'.

Alfa JTS induction kits

Improving air intake on the Alfa JTS

You need fuel and air 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 job to pull fuel and air into each cylinder but this has a knock on effect with the air flow sensor.

It is not unusual that there's a restriction in the air flow sensor MAP/MAF/AFM on the Alfa JTS when considerably more air is being drawn 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 sapped bhp and torque at a much lower level.

Engines intake headers flow the on the suck phase from the air cleaner and allow it to be fed into the engine and mixed with fuel.

Design and flow characteristics of the Air Intake manifolds can make a large change to fuel mixing and power on the Alfa JTS.

We often see plenum chambers are in dire need of motorsport parts, although some OEM provide fairly well optimized plenum chambers.

Larger Alfa JTS valves, doing a bit of port work and head flowing will also raise power, and importantly will allow you to get an improved power increase on other upgrades.

Alfa JTS performance cam tips.

Some Alfa JTS engines respond better to less aggressive cam durations than others.

The map and fuelling also will say much on the torque gains you'll hit.

Longer 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 tend to boost the power throughout the rpm range, you might lose a little low end torque but top end will be better.

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

A Competition cam won't do well if driving in heavy traffic.

You should ideally match your torque band to your typical driving style so for a typical daily driver stick with a shorter duration Alfa JTS cam

Stage 1, 2 and 3 mods for the Alfa JTS

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 Alfa JTS parts:

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

Stage 2 Alfa JTS parts:

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

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

Stage 3 Alfa JTS parts:

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

The Alfa JTS engines respond well to upgrades and thanks to their popularity there are plenty of mods and tuning parts out there.

ECU mapping helps release the full potential of all the upgrades you've done to your Alfa JTS.

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 rely on the upgrades you've done and the condition of your engine.

Turbo modifications on the Alfa JTS

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 Alfa JTS.

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.

If the engine has a turbocharger tuning mods are going to net you a larger power gain and you will discover turbocharged engines use more solid components.

There are tuning limits for every engine, with some being incredibly solid and some only just able to handle stock power

We recommend you find these limitations and fit higher quality components to utilize the power.

We see many drivers spending a lot of money on turbo upgrades on the Alfa JTS only to have the whole thing go up in smoke soon after it's first rolling road session.

Big turbo chargers tend to experience low end lag, and small turbo chargers spool up quickly but do not have the top end bhp gains.

Thanks to new tech the range of turbo units is always moving on and we are seeing variable vane turbo units, where the vane angle is altered according to speed to lower lag and increase top end power.

Twin scroll turbo units divert the exhaust gases into 2 channels and feed these at differently designed vanes in the turbo charger. They also boost the scavenging effect of the engine.

Beefing up the air intake by adding a supercharger or additional turbo will help you achieve very large power gains, although more complex to setup. We have this feature on twinchargers if you want to read more.

Tips about fuel supply on the Alfa JTS

Don't forget to ramp up the fuel delivery when you are increasing the torque - it makes the car more thirsty. Experienced tuners recommend to over specify your injector capacity.

The accepted safe increase is to add 15% capacity when specifying an injector, which takes into account injector deterioration and gives a bit of spare capacity should the engine require 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 Alfa JTS performance exhaust upgrades

You should look to upgrade your exhaust system with an upgraded one is if your exhaust is actually causing a restriction in flow.

On most factory exhausts you'll find the exhaust flow rate is ok 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.

Don't go with the biggest exhaust you can source you'll slow the exhaust 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.

Usual exhaust restrictions can be traced to the filters installed, so adding a faster flowing performance 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 Alfa JTS

Like most engines an Alfa JTS, 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 Alfa JTS, failure to do this will exacerbate engine wear, on a tuned Alfa JTS 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 Alfa JTS why not pop over to the forums at TorqueCars where you can chat about Alfa JTS tuning options and read about others projects who may be planning to do similar modifications on their Alfa JTS.

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