how much power will i gain with green coten airfilter eco tech vlve and full stainless without middle box

I think the again is around 0BHP + or - 1.

ECO Valve will reduce your cars MPG aswell as doing nothing to the engine or fuel.

Joske

it true

Ecotek valve will NOT reduce your cars MPG. Nor will it increase it. It does very little, though I suspect there can be emissions issues if you fiddle with it just before testing, as the ECU/lambda etc need to adjust to account for it.
On a modern engine though, its pointless. (I have one fitted btw,lol)

Buzz (formerly LightWarrior)
The champion of the Bravo 1.4
Owner of the Bravo 1.8
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And i reckon you'll get a 1bhp gain from a cotton air filter and a less restricted exhaust. It makes a deep-as-you-like rumble, so i suggest you fit the middle muffler after all!

Buzz (formerly LightWarrior)
The champion of the Bravo 1.4
Owner of the Bravo 1.8
Member Page