The first step in extracting power from the B58 engine requires no hardware changes, this is a software-only upgrade. The ECU software follows the linear torque delivery of the stock ECU tune through the low to mid-range while in the higher rpm range, where the standard power curve starts to flatten off, we keep the power climbing, holding the peak power right up to the limiter where as much as 460HP can be seen, Petrol Particulate Filter (PPF) typically see slightly lower results.

We retain this flat torque delivery for driveability reasons, most of the 40i models do not come equipped with an LSD, with this in mind, additional torque moments or spikey delivery can provoke unwanted wheel spin, and show up chassis limitations. Another reason for limiting the torque is to ensure we do not have any fuel rail pressure drop, typically we run 450-460lbft, and although slightly higher levels can be seen we would rather not run the fuel pump at 100%, and leave some headroom for pumping losses over time.

With our 'Stage' software upgrades the following features are included:

• Vmax Removal (Speed limiter removed)
• Sports Displays recalibrated to suit new outputs
• Enhanced over run (Optional)

Expected Results, based on our Dyno Dynamics rolling Road:

440-460HP with 450-460LBFT

An additional step towards improving restrictive exhaust flow of the stock exhaust is the removal of the catalyst in the downpipe, upon removal of the standard catalyst it is recommended to install a sports cat to retain MOT legality, or a full de-cat pipe can be utilised for optimal gains if the vehicle is to be for track use only. With the free-flowing downpipe installed fueling can be optimized and new lambda targets set, and boost levels and ignition timing can be optimised, taking into account the less restrictive exhaust system.

The standard cat-back with or without PPF filter can be still retained, we do highly recommend removing the PPF Filter, however. The stock exhaust is not deemed to be overly restrictive at this stage due to its large bore design, improvements can still be made with replacement with free-flowing bends.

Low-end response is improved and turbo lag is reduced which will be noticeable on the road, the torque curve will be held similarly to stage 1, with an extra 10-15LBFT  however power at higher RPM will increase by 10-15hp. With the limiting factor at this level of the tune being the limitation of the fuel pressure system - this is upgraded as part of a plus stage.

With our 'Stage 2' software upgrades the following are included:

• Vmax Removal (Speed limiter removed)
• Sports Displays recalibrated to suit new outputs
• Catalyst code removal to avoid EML lights
• Cold start delete (removal of high / loud idle) (optional)
• PPF delete software (If applicable)
• Enhanced overrun (Optional)

Expected Results, based on our Dyno Dynamics rolling Road:

450-470HP with 460-470LBFT

The final hardware change for maximising the standard turbochargers efficiency range, which allows up to ramp up the mid-range boost to gain optimal airflow is a fuel pump upgrade. The issue of the standard fuel system becomes clear if attempting to run much higher torque than 470-480lbft, then the fuel pressure will drop - this can cause limp mode or worse engine damage from lack of fuel pressure. To resolve this and to run greater torque levels (with requires more fuel volume) an upgraded high-pressure fuel pump is installed (HPFP) this allows more fuel volume per camshaft stroke (camshaft driven pump) thus allowing more fuel volume without pressure drop.

When upgrading the fuel pump there are a few options, and we advise you to think about the future plans if any - if planning to run over 550HP on pump fuel, or even with ethanol blends an aftermarket pump is recommended, otherwise for the base upgrade we use a 'TU' fuel pump from the later B58 models (Z4 / Supra)

Now the fuel system is up to the standard we have two options of tuning. either run a flat ~500lbft or curve upwards to 540lbft. We would highly recommend a LSD is installed for the latter level of power delivery, otherwise, we would suggest running a flatter delivery to keep wheel spin down.

With our 'Stage 2+' software upgrades the following are included:

• Vmax Removal (Speed limiter removed)
• Sports Displays recalibrated to suit new outputs
• Catalyst code removal to avoid EML lights
• Cold start delete (removal of high / loud idle) (optional)
• PPF delete software (If applicable)
• Enhanced overrun (Optional)

Expected Results, based on our Dyno Dynamics rolling Road:

470-490HP with 500-540LBFT

Stage 2+ Overlay comparison - the limiting factor is the fuel pump, once this is replaced the under-curve gains increase dramatically 

The stock turbochargers are the limiting factor when it comes to the next stage of performance, with compressors/turbines limiting any more flow. With larger compressors and turbines installed into the stock turbo housings, these 'Hybrids' allow a much great flow of airflow and exhaust gas turbine flow. High-flow downpipes are a must at this state of tune, and a cat-back system is advised for optimal gains.

Charge temperatures start to creep up when increasing the boost pressures - so depending on target HP and usage we would advise a charge cooler radiator upgrade as well. Water Methanol would also be a recommended upgrade when looking for maximum output. We have seen good gains from installing a Port Meth system.

With our 'Stage 3' software upgrades the following are included:

• Vmax Removal (Speed limiter removed)
• Sports Displays recalibrated to suit new outputs
• Catalyst code removal to avoid EML lights
• Cold start delete (removal of high/loud idle) (optional)
• PPF delete software (If applicable)
• Enhanced overrun (Optional)
• Switchable map modes (ECUTEK Racerom Required)

Expected Results, based on our Dyno Dynamics rolling Road:

530-700HP with 530-650LBFT

The next level. Once the Standard Hybrid or bolt-on turbo route has been exhausted, although we deem this more than enough for most people - there are those who want to send it to the moon!

At this level of tune, it is worth thinking about much more than just the powerplant upgrade, but everything else also - from upgrading Gearboxes, engine mounts, engine internals, inlet manifolds, etc! With this in mind, these are not cheap upgrades, and pricing requires us to know your exact goals/budgets and requirements.

We offer motorsport turbochargers with beautiful hand-made tubular exhaust manifolds to high flowing Motorsport Turbochargers

Expected Results, based on our Dyno Dynamics rolling Road:

700-900HP 650-750LBFT