I dont know how accurate the information i have been given is but any advice or help would be appreciated.
My car has got full hks induction package and dump valve, however the exhaust still has the cat in place but a four inch system from cat back, i have been told to unlock valuable bhp and to free up acceleration i need to remove the cat ??? This does make sence to me,but i have heared night mare stories when it comes to MOT time relating to failing the emmission.
my car is a my94 jap import
Mick

[Edited by ImprezaWRX - 9/19/2002 4:11:26 PM]

 

The down Pipe (which contains the first cat) is quite restrictive so for maximum gains u will have to replace it with a twin dump DP, but come Mot time u will need a cat to pass AFAIK some peeps 'borrow' a cat for a small fee for testing...

Cheers

 

The other thing you can do is fit an exhaust with a freer flowing sports cat. Several exist, such as Power Engineering, APS (go to JW racing in UK), I think Graham Goode also. These will give you most of the gains of a de-cat, but without the hassle of MOT emmissions failures. Downsides? Tend to cost a bit more, and I still can't see they'll be quite as good as a full de-cat, as there is still some restriction to exhaust flow, albeit much less than in a standard car.

 

Depends on the mot station, BUT as far as I'm aware, you don't need cats on a 94 import, best ask your mot tester for his take on it.
Ron.