What happens to VED when you modify an engine?

The VED for my 2008 Mercedes-Benz SLK 350 is £485. Other SLK 350s of the same age have lower VED, with some owners paying just £265. Is it possible to re-chip the engine and lower the CO2? Would this reduce my VED?

Asked on 20 October 2014 by Stag66

Answered by Honest John
No. The VED remains based on the ECDC emissions the original car was tested to.
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