1.4 cat on valver, how restrictive?

[AmDaMan]

Hi, basically I've still got my 1.4 cat on the willy bottom end, and a valver stainless catback exhaust. How restrictive will that be? Will I see gains by fitting a decat or a valver cat?

Also should I change the valver exhaust / inlet manifold for a willy one?

Running a 1.8 head on a megane bottom end.

[Rich]

id change the zorst manifold and downpipe and get a willy de-cat, or beter still get a de-cat with rotating flange then you can borrow my catr at mot time ;) :lol:

inlet manifolds are same

[AmDaMan]

already have an adjustable cat.

What are the main downpipe differences? Why do some people use valver manifolds on their willys?

[Rich]

there is a massive thread about valver or willy manifolds if you do a search. at the end of the day though, if a willy engine was meant to have a valver manifold, why would tthay have developed the willy one? :wink:

laughing then with an adjustable de-cat, will be more responsive witth it on

[arj256]

With my 1.2's cat it was smaller than the 1.8 16v cat. So the lower cc ones are just sport cats really :wink: