De-cat question - Alfa Romeo Forum
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De-cat question

As an owner of an Alfa of just one week, I wish to free up some power on my 2.0L - but dont really want to make the car much louder. I am aware that an effective mod is to remove the mid section siliencer or de-cat the car. Am i correct in assuming, out of the two, the cat bypass is the most effective?

If I keep all the silencers in place and install the decat mod (straight pipe) would I achieve my aim of more BHP without significant change in volume?

How many horses would I free up?

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i don't know the answer myself but it might get more attention if you post your question in here

Tuning & Upgrades - Alfa Romeo Forum

Also if you do a search there might already be a thread on this topic with the answers you need and any help already posted by somebody,

Hope this helps
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Cybox do a decat silenced pipe about 65, it looks and is reasonably well made in stainless steel except the longest joint is rolled rather than welded.
Had a slight blow in mine along the rolled seam and contacted cybox who said its normal, so had an exhaust centre seal it up.

The gains are noticable but only slightly on a 2.0ltr CF2 car and the fuel consumption is slightly up, but the noise is great and typical of older Alfa's with a nice rasp and a howl higher up the rev band and it definately revs more freely.

I am quite light on the throttle through villages as lower down the rev range it can sound a bit racy.

EDIT; 1/08/2011 ; Oh there is a nice bark when the engine is first fired up, i have just had my cat refitted for the MOT next month and can say that the decat
is worth every penny, still sounds good with the cat but nowhere near as rorty as the cybox so it is definately going back on after the MOT.

Last edited by alfafanatic100; 01-08-11 at 22:29.
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