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451 Petrol Remapping

Mod Description
Remaps replace your car's software which increases the power of the engine and can increase MPG too
Mod Details
PremiumNo Difficulty Mod ID791 CreditT4P For451 Fortwo Link Copy to Clipboard

451 Remapping

Despite the smart fortwo 451 being out since 2007, there isn’t that many people remapping them. The reason for this is that it’s no longer a simple “plug into the OBD port and write a map to the car” like it was on the fortwo 450 and Roadster. Any limp brained garage worker could do that and they still do. Remapping the 451 is a bit more involved.

Doing It Properly

As you are going to be paying good money for a remap, you should insist it is done correctly.

1. Does the remapper have a workshop that you can visit when you like?
2. Is the remapper clear on the price or vague about extras?
3. Do they have a dynometer (rolling road) to prove before and after results?
4. Are they even a registered company?*

*If not, they might not be insured if something goes wrong as they work on your car. You can search for company names to see if they are official registered companies. Type the business name in here or check companies house.

Film Time!

The Remapping Process

The car is driven onto the dyno, strapped down securely and warmed up.

The rear wheels are the driven wheels on the 451 so they are placed onto 2 large rollers. As these rollers are spun by the acceleration of the car, the dyno computer calculates the torque and the brake horse power being developed throughout the rev range of the car.

My 451 is a 2011 Pulse Turbo. It has been noted that 2011 manufactured “Non Brabus” turbo engined 451’s actually have the Brabus remap as standard. It is believed that this was done to negate any power loss that had been added when smart started fitting the Euro 5 emissions compliant exhausts. The Euro 5 exhaust is about 4 times longer than the Euro 4 equivalent.

So, it was no shock when the standard dyno run showed 108ft/lb of torque and 98bhp. These are almost perfect 451 Brabus output figures. We also now know the dyno is accurate.

The boot is opened, side panel removed and ECU taken from the car. This is Tony from Tune4Performance working on my car, not the old guy from the Dolmio advert.

Some components are soldered to the board which allows the serial IO pins of the main chip to connect safely to the main wiring connection. A laptop connects directly to the ECU and a special piece of software overwrites the old map with a new map.

The previously added components are removed, the ECU put back together and placed in the car.

The dyno test is done again to insure that the remap has been correctly installed and that the figures are suitable for that type of car with the setup you have.

The car was 10 weeks old when I had this remap installed. I had performed no other engine upgrades at that time. No performance filter, silicone pipes or performance exhaust.

Considering that, the extra 14.1ft/lb of torque and extra 18.7bhp made a noticeable increase when driving. The extra torque made the pull away far more rapid and the bhp increased top speed.

So, You Recommend Tune4Performance For 451 Remaps?

Sadly Tony retired so there are no remappers I can recommend personally. However, many people have had great results with Ian at Big Performance so maybe go and see him.