Modding uprating the AlfaRomeo Alfa Twin Cam engine!

Tuning guide "Alfa Twin Cam Modifications"

Alfa Twin Cam Modifications Guide

How to modify and upgrade the AlfaRomeo Alfa Twin Cam

"Comprehensive guide to tuning the AlfaRomeo Alfa Twin Cam engine!"

TorqueCars are always seeing threads requesting information on how to improve the Alfa Twin Cam from people inquiring about getting more power from the Alfa Twin Cam and wanting to know what are the greatest Alfa Twin Cam power upgrades. So let us look into AlfaRomeo Alfa Twin Cam parts and outline the best upgrades on this great engine and point out some potential pitfalls along the way.

The AlfaRomeo Alfa Twin Cam make awesome project engines and with the optimum performance parts like remapping, turbo improvements and camshafts you will certainly increase your driving enjoyment.

Car Tuning Tips will look into Alfa Twin Cam tuning and report on the best modifications.

When talking about the optimum parts for your Alfa Twin Cam engine, we are going to focus on the upgrades that give the biggest return for your cash.

Alfa Twin Cam induction kits

Improving air intake on the Alfa Twin Cam

You need air matched to fuel for an engine to work. If there is insufficient fuel then it will run lean, if there is little flow of air it runs rich resulting in lost power which risks damage to the Alfa Twin Cam. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So Shoving more fuel and air into the Alfa Twin Cam engine is the aim to any engine modification project.

It is common that there's a limit in the air flow sensor MAF/MAP on the Alfa Twin Cam when a lot more air is being pulled into the engine.

We note 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor was restricting torque at a much lower level.

Intake flow the air from the filter and allow it to be fed into the engine cylinders.

Design and flow rate of the Headers can make a substantial change to fuel delivery on the Alfa Twin Cam.

Most intake manifold are ripe for aftermarket tuning parts, although some makers provide reasonably good intake manifold.

Fitting big valve kits, carrying out port work and head flowing will also increase bhp, the fantastic side effect is it will allow you to get raising the bhp increase on other parts.

Alfa Twin Cam performance cam tips.

Some Alfa Twin Cam engines respond better to more aggressive camshaft durations so set your engine up on a rolling road.

The engine timing and fuel pump and injectors also will make differences on the power gains you'll hit.

Longer valve durations can alter the power 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.

Altering your Alfa Twin Cam camshaft will make a dramatic difference to the engine torque. Choosing a higher performance camshaft profile raises the torque accordingly.

NB: Fast road camshafts commonly boost the bhp and torque through the rev range, you might lose a little low down torque but the top end will be higher.

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 Race camshaft is not great in heavy traffic.

You should ideally match your torque band to your preferences so for a road car stick with a fast road Alfa Twin Cam camshaft

Stage 1, 2 and 3 mods for the Alfa Twin Cam

Stage 1 Alfa Twin Cam parts:

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

Stage 2 Alfa Twin Cam parts:

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

Stage 3 Alfa Twin Cam parts:

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

The Alfa Twin Cam units respond well to upgrades and we note that there are quite a few choices of mods and tuning parts about.

A remap helps unlock the full potential of all the tuning parts you've done to your Alfa Twin Cam.

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 end result usually rely on the tuning parts you've done and the condition of your engine.

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

Turbo modifications on the Alfa Twin Cam

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 Twin Cam.

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

If your car is turbo charged parts are relatively easy and turbocharged engines are made with harder and stronger components.

There are common areas of failure for every engine, with some being incredibly solid and some only able to handle stock power

See where you'll find these restrictions and upgrade to higher quality crank and pistons to utilize the power.

We've seen mechanics spending a a stack of money on turbo charger upgrades on the Alfa Twin Cam only to suffer the indignity of watching the engine throw a rod just after it's used in anger.

Large turbo units tend to suffer no power at low rpm, and small turbo units spool up really quickly but won't have the peak rpm engines power gains.

Thankfully the choice of turbochargers is always evolving and we are seeing variable vane turbochargers, permitting the vane angle is altered according to speed to lower lag and increase top end performance.

Twin scroll turbochargers divert the exhaust flow into two channels and feed these at differently profiled vanes in the turbo. 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 power gains, although more complex to configure. We have this article on twincharging if you want to read more.

Tips about fuel supply on the Alfa Twin Cam

You will need to ensure that the engine is not starved of fuel so will need to increase the fuelling when you start exceeding 20% of a torque hike. Don't forget to be generous with your injectors flow rate.

As a rule of thumb add 20% when buying an injector, this accounts for injector deterioration and provides a bit of 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 Alfa Twin Cam performance exhaust upgrades

You should look to improve your exhaust system with an upgraded one is if your exhaust is actually creating a restriction.

On most factory exhausts you'll find your flow rate is good 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.

Do not go with the biggest exhaust you can get this will 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.

Usual exhaust restrictions can be traced to the catalyst installed, so adding a better 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 Alfa Twin Cam

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

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