BMW 420i chip tuning — the Turkish 1.6L 4 Series

The Turkish-market 420i (G22 Coupé / G26 Gran Coupé) carries the exact same 1.6L B48B16 engine as the 320i. The badge says 420, but under the hood it's 1,597 cc. Same engine, same packages: 280, 300 and 320 HP, from your own phone.

Why is the 420i 1.6L in Turkey?

In Turkey the entry 4 Series uses — for tax-bracket reasons — not the 2.0 but the 1.6L B48B16 (MG1CS003 ECU), the identical unit found in the 320i and 520i.

So the calibration is the same as the 320i: stock 170 PS to 280 and 300 HP by software alone, 320 HP with a downpipe and suitable fuel.

The G22 Coupé and G26 Gran Coupé differ in weight/aero; the engine and calibration are the same. Full output shows on a well-maintained car.

What does the software feel like on a 420i?

The Turkish-market 420i looks like a 4 Series but shares the 3 Series entry drivetrain: 170 PS and the 8-speed automatic. The coupé body is a little heavier than the 320i, and in factory trim that shows as a "waiting for boost" feel between 1,500 and 2,500 rpm. That is the first thing the calibration addresses: torque request and boost curve are brought forward, so the car pulls on overtakes and hills without dropping a gear.

The 280 and 300 HP stages run with the stock downpipe and stock OPF; you open up the exhaust sound with the crackle setting as much as you like. 320 HP needs a downpipe — the same downpipe fits the Gran Coupé (G26) and Coupé (G22), and OPF/DP calibration is included.

A question we get often: "Is the 420i M Sport different?" No — the trim changes looks and suspension, the engine and ECU stay the same. Stages and prices are identical to the 320i.

Power by stage

Factory output 170 PS. Figures in metric horsepower (PS).

Horizontal bar chart: stock 170 PS, 280 HP package 280 PS, 300 HP package 300 PS, 320 HP package 320 PS.Stock170280 HP280300 HP300320 HP320

280 and 300 on stock hardware; 320 needs a downpipe and suitable fuel. The stage is chosen from datalog data.

Packages and power stages

280 and 300 are delivered on stock hardware, software only. 320 needs a downpipe and fuel support — turbo and injectors stay stock on all three.

PackagePowerHardwareGain
Stock170 HPfactory—
280 HP Package280 HPstock hardware+110 HP
300 HP Package300 HPstock hardware+130 HP
320 HP Package320 HPdownpipe + fuel+150 HP

Figures are metric horsepower (PS) as used in Turkey; the UK bhp equivalent is slightly lower (170 PS = 168 bhp). 320 is not delivered on stock hardware — a downpipe must be fitted and the fuel must suit it; that is Stage 2 territory. Which stage suits your car depends on fuel quality, maintenance and what we see in a road log — datalog analysis exists for exactly that.

Included features

Alongside the power stage, toggles you control from the app. For track / closed-road use; road legality is the user's responsibility.

Sound

Crackle / Pops (adjustable)

Controlled crackle and pops from the exhaust. Rev range, speed and intensity are set from the app — without risking engine health.

Cold

Cold Start Delete

Silences the high-idle, noisy warm-up on cold starts. Quiet mornings — fully off or off once warm.

Speed

Speed Limiter Off

Removes the factory electronic speed limit (Vmax).

RPM

RPM Limiter

Adjusts the rev limit to suit your stage.

Exhaust

OPF / DP Calibration

Compatible calibration for particulate-filter delete or downpipe cars.

Cooling

Sport Cooling

Earlier, more aggressive cooling for high load and track use.

Packages and prices

Enter your VIN, pay right here on the site; access is granted automatically after payment. Prices in EUR.

Flasher

€350
  • Write your own or your tuner's file
  • Crackle, OPF/DP, Vmax, cold start, RPM included
  • Original backup + return to stock
  • No ready HP maps included
View & Buy

Full: Flasher + 280/300 + 320

€900
€1050 save €150
  • Flasher + all three stages
  • 320 needs downpipe + suitable fuel
  • €150 cheaper than buying one by one
  • Original backup + return to stock
View & Buy

Already own the Flasher? 280/300 HP package €500, 320 HP add-on €200, both together €700. Pick your car and situation on Find my package to see the right price. You can check your car's eligibility for free from the app before buying.

You pick the package in the app

You choose the stage and the extra toggles on the app's Flash screen. The package card shows the stages authorised for your VIN — without access, the option does not open.

Exhaust sound (crackle), speed limiter and cold-start behaviour are separate switches; which ones suit your car we decide together.

Once the write starts, progress and a log of every step scroll on screen. You do not need to leave the app before it finishes.

The MOSTUNED app Flash screen: 280, 300, 320 and Stock options, crackle, limiter and cold-start settings
Captured in demo mode — simulated vehicle, no real connection.

420i FAQ

Is the 420i really 1.6L?

Yes. The Turkish 420i ships with the 1.6L B48B16 — same engine as the 320i. Badge 420, engine 1,597 cc.

Are both G22 and G26 supported?

Yes, both the Coupé (G22) and Gran Coupé (G26). Same engine, same packages.

Same file as the 320i?

Same engine family (B48B16 / MG1CS003), so the stages are the same; every write is prepared for your VIN.

Refunds?

No refunds once delivered; see terms of use.

Related

Contact

Not sure?

Send your model, hardware and goal — we will pick the right package together. We do not sell what does not fit.

Message on WhatsApp

WhatsApp