What is the best product if I would want to remove the first cata, what is the avg. power gain, could it give problems with MOT and how much does it cost?

Cheers,
Ruud.

Scoobysport do a downpipe which replaces 1st cat. Had several good posts but someone else'll have to advise on power gains/dyno readings etc or you could try searching the posts on technical for 'downpipes'? I visited Pete the other day and was going to get one but it doesn't fit in with MOT regs so you'd have to change it back again for an MOT http://bbs.sidc.co.uk/frown.gif

Hi Ruud,
I have tried various combinations.Firstly I tried the scoobysport back-box with Ramair panel filter.I found that it gave me only minor gains,but others have seen 10/15 bhp,and simular torque figures.
Next I changed the front down pipe.this is the most restrictive part of the exhaust.At the time the HKS pipe was the only one readily available.
Here I started to get some major gains;about 22bhp/20ftlbs of torque,but mainly the ON ROAD performance was very impressive.

Scoobysport then started making a down pipe.
It's design is far better than the HKS;So I had to try it!
I was only expecting minor changes,but the improvment was worth the change.
On the rolling road the peak gains were minor
,bhp about the same,and 5ftlbs of torque;BUT,between 3500rpm,6500rpm,I gained as much as 20bhp/ftlbs.I had also dumped the
Ramair filter in favor of a Piper x induction
kit.
Try to change both the front pipe,and rear box,as these will give you the biggest gains,and they work Very well together.The Scoobysport down pipe is VERY GOOD,as is the rear box(there are cheaper options on the box)but I dont know how good they are.
Of course any gains that you get will depend on which car you have(uk/import).
You will have emmision problems(Mot/Dutch?)but it's worth it !!!

Scoobysport down pipe £215.00 approx'
"" "" rear box £300.00 ""
Piper x induction kit £100.00 ""

Hope this helps, Mark.A.
MY98 STi4 + a few bits.

[This message has been edited by R19KET (edited 15-04-99).]

I'm thinking of replacing what we call the front-pipe which is has the cat inside.

Is this front-pipe the same thing as the down-pipe ? I've changed my exhaust from a 2 peice setup into a single peice apexi. I've been told a front pipe change would make loads of difference.

Thanks for clearing this up http://bbs.sidc.co.uk/wink.gif

I have a Scorpian Gp A system with 3' through bore and 4' tail pipe. it comes with a cat replacement pipe. This must be a second cat in the system? Does anyone have experience of removing this cat? will it cause any mechanical problems? Any power gains? any noise? anyone got one fitted?
Its not been fitted yet/ July delivery of car,fingers crossed.
Cheers http://bbs.sidc.co.uk/smile.gif

Try the Supersprint group N part !!!
www.supersprint.com

I think it's available in Netherlands, too.

ric

the importer for the netherlands is
CARSPORT HOLLAND
Phone: 0294/417641
Fax: 0294/480430
here are the partnumbers
960401 Front pipe Stainless steel F540:00 exe btw

>960413 Center pipe Stainless steel F473:00 exe btw

>960405 Rear silencer Oval 120x80 F921:00 exe btw


best regards,
ps rebuild the orig backbox 4 hours work!!

The STI V has only ONE cat. Dont know about the MY99.

Cheers

Jonathan