Does replacing your cat with straight through pipes really make any different? what are some of the good and bad points?
Louder? more or less fuel?

 

MOT failure.

 

Big difference. Increases power, decreases fuel consumption (thats how I got it past Mrs C ), deepens rather than increases exhaust note.

I would say the most effective mod on an Impreza

 

just been MOT, nice. And it a E36 325i if that make any differents.

 

My last car was one of those.

You could be looking at getting 215bhp ish if you remove the cat.

I wouldn't tho cos you'll have to replace for its next test, assuming it's k reg or later.

 

215brake woohhooo. It a Jreg..

 

No excuses, do it

 

Yeah why not.

Get a decent stainless steel jobby.

 

Depends on the car. some are designed to utilise the back pressure the cat creates (??). Could potentially affect reliablility I suppose. like I say, all depends on what car it is and how that cars exhaust system is designed.

 

well i've seen replacement pipes for sale £189. and a magnex cat back for £265.

you know any good www to buy from.

Thanks

 

Two cats on a Scooby. Remove the mid section one for a straight through pipe. I did this and noticed no difference in fuel consumption, sounds great, some minor torque benefits and mine passed its MOT no problems, but it needs to be warm though.

Do it - just watch the insurance.

 

Did it on an old (H reg) Audi 100 5 cyl, made it quicker and it sounded better, like a Quattro and it even had a decent overun crackle, cost thirty quid for a bit of correct diameter pipe (use a vernier) four clamps and some exhaust bog.

Local fast fit did it first, they use a bit of corroded pipe from an exhaust they removed from another car and generally made an **** of it, if you want a job doing properly....

 

got the car booked in for Tuesday to have the cats off, meeoooww.
and it will still pass MOT cos it a 1991 J plate.
power for free!

 

I've removed my CAT and replaced it with a straight through pipe.

More power, more torque, more noise. It removed the flat spot I had at 3500rpm and yes if gives more MPG.

As mentioned it is an MOT fail so I've got to put the CAT back in for a few weeks each year.

 

Big Col wot car you have?
my 325i is jreg 1991.
so it will pass mot. because you can do a mot test for a non cat car. the garage has told me this.

 

'94 Corsa GSi

 

nice!