Modding tuning and best performance upgrades on the Chrysler 6.2 Hellcat Hemi engine!

Everything You Need To Know About "6.2 Hellcat Hemi Modifications"

How to modify and upgrade the Chrysler 6.2 Hellcat Hemi

"Comprehensive guide to tuning and performance parts on the Chrysler 6.2 Hellcat Hemi engine!"

Sites like TorqueCars are regularly getting posts requesting info on how to improve the 6.2 Hellcat Hemi from people inquiring about getting more power from the 6.2 Hellcat Hemi and wanting to know what are the best tips on 6.2 Hellcat Hemi upgrades. So let us look into Chrysler 6.2 Hellcat Hemi tuning mods and outline the best modifications on this great engine and point out some potential pitfalls along the way.

Here we look into 6.2 Hellcat Hemi tuning and report on the greatest modifications. Chrysler 6.2 Hellcat Hemi are popular engines and with the best tuning modifications like a remap, turbo improvements and camshafts you will dramatically maximize your driving opportunities.

The best 6.2 Hellcat Hemi upgrades on an engine are as we have found the ones that give the biggest return for your money.

We won't be swayed by popular 6.2 Hellcat Hemi upgrades, they need to be cost effective.

6.2 Hellcat Hemi induction kits

Improving air intake on the 6.2 Hellcat Hemi

You need fuel and air for an engine to work. If there is not enough fuel then it will run lean, if there is a lack of air it runs rich resulting in lost power and potentially damaging the engine. We'll pick up on fuelling later in this article but for now we shall look at air supply.

So the goal to any performance tuning project to push air and fuel into each cylinder but this has a knock on effect with the air flow sensor.

It is not unusual that there is a limitation in the air flow sensor MAP/MAF/AFM on the 6.2 Hellcat Hemi when considerably more air is being drawn into the engine.

You'll see that 4 bar air sensors coping with quite large power gains, whereas the OEM air sensor sapped torque at a much lower level.

Headers flow the on the suck phase from the air filter and allow it to be drawn into the engine cylinders with fuel for the squish phase.

Design and flow characteristics of the Air Intake manifolds can make a substantial change to fuel mixing and power on the 6.2 Hellcat Hemi.

Many mass produced engine intake headers are ripe for motorsport parts, although a few OEM provide reasonably well designed intake headers.

Fitting big valve kits, doing a bit of 6.2 Hellcat Hemi port enlargement and head flowing will also boost torque, this will raise potential for an improved torque increase on other tuning parts.

6.2 Hellcat Hemi performance cam tips.

Each engine responds better to more aggressive camshaft durations so set your engine up on a rolling road.

The map and fuel pump and injectors also will say much on the torque gains you'll make.

Extending exhaust or intake 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 torque gains are on offer for camshaft upgrades.

NB: Fast road cams normally bump the power across the rev band, you may sacrifice a little low down bhp but the higher rpm power will improve.

Competition cams, bump the higher rpm power band but as a result the car will not idle smoothly and low end power nearly always suffers.

For a car driven daily you must carefully try to optimize your power band to your driving style.

I'd be gobsmaked if you have found a 6.2 Hellcat Hemi Competition camshaft is a pleasure to live with when driving in heavy traffic.

Stage 1, 2 and 3 mods for the 6.2 Hellcat Hemi

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 6.2 Hellcat Hemi parts:

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

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

Stage 2 6.2 Hellcat Hemi parts:

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

Stage 3 6.2 Hellcat Hemi parts:

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

Carefully think through your options and then buy your upgrades and set yourself a power target to avoid wasting your time and money.

A remap helps to establish the full potential of all the parts you've done to your 6.2 Hellcat Hemi.

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 your mileage usually differs on the parts you've done and the condition of your engine.

Turbo modifications on the 6.2 Hellcat Hemi

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 6.2 Hellcat Hemi.

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

When a car has a turbocharger tuning parts are going to make more power and you'll see that turbo charged engines are built with more solid components.

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

Discover these limitations and upgrade to forged components to handle the power.

We see many people spending a loads of money on turbocharger upgrades on the 6.2 Hellcat Hemi only to have the 6.2 Hellcat Hemi catastrophically fail just after it's been finished.

Large turbochargers tend to experience low end lag, and low capacity turbochargers spool up much more quickly but don't have the peak end power band gains.

We are pleased that the selection of turbo chargers is always moving on and we commonly find variable vane turbo chargers, allowing the vane angle is altered according to speed to lower lag and increase top end performance.

Twin scroll turbo chargers divert the exhaust gases into two channels and feed these at differently angled vanes in the turbo. 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 install. We have this article on twincharging if you want to read more.

Tips about fuel supply on the 6.2 Hellcat Hemi

You will need to ensure that the engine is not starved of fuel so will need to uprate the fuelling when you start extending past 20% of a bhp hike. We strongly recommend you to be generous with your injector capacity.

As a rule of thumb add 15% to the flow rate when specifying an injector, this accounts for injector deterioration and allows 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 6.2 Hellcat Hemi performance exhaust upgrades

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

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

Sports exhausts can usually air flow through the engine but avoid an exhaust that is too wide or you could will reduce the flow rate. Stick to one and a half to two and half inches as a rule of thumb.

Usual exhaust restrictions are traced to the catalysts installed, so adding a freer 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 6.2 Hellcat Hemi

Like most engines an 6.2 Hellcat Hemi, 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 6.2 Hellcat Hemi, failure to do this will exacerbate engine wear, on a tuned 6.2 Hellcat Hemi 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 6.2 Hellcat Hemi why not pop over to the forums at TorqueCars where you can chat about 6.2 Hellcat Hemi tuning options and read about others projects who may be planning to do similar modifications on their 6.2 Hellcat Hemi.

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