1994 900SE 2.5 non turbo/non convert exhaust

[gthomp0805]

I want to remove the catalytic converter from the car and replace with a straight pipe to the muffler to see if I can eliminate the converter as my source of power loose. Can anyone tell me what I need to do this? ie. pipe length, diameter, gaskets, clamps etc or direct me to a link that would explain. I want to make sure I get all the right parts from the auto parts store the first time because once it is apart, going back a second time will not be an option without alerting the police that I am coming.

[hkayssi]

Originally Posted by gthomp0805

I want to remove the catalytic converter from the car and replace with a straight pipe to the muffler to see if I can eliminate the converter as my source of power loose. Can anyone tell me what I need to do this? ie. pipe length, diameter, gaskets, clamps etc or direct me to a link that would explain. I want to make sure I get all the right parts from the auto parts store the first time because once it is apart, going back a second time will not be an option without alerting the police that I am coming.

Is that legal in your sate? If not, don't you have to pass inspection in order to renew the registration?

[gthomp0805]

No it is not legal but I dont want to spend 300.00 on a new one unless I am sure it is the problem.

[Tweek's Turbos]

Ahh, my advice is to remove the exhaust, bring the parts to you fav muffler shop, and have them weld in a test pipe for the car you intend on Ice racing up in Northern NY.

[Pete67]

If you de cat the V6 you will get a tiny gain to your B.H.P. but will lose large amounts of mid range torque, i would have thought the car will feel very similar to how it does now, lacking mid range punch.

Why not have an emissions test to see if the cat is still functioning?

[gthomp0805]

The local garages will not scope a car older than 1996. I don't want to weld a pipe in place because if that is the problem, (but it appears that it wont make much of a difference) I want to be able to replace it. Any other ways of checking it. I have had 3 mechanics look at the car and they believe it is the cat but there is no guarantee.

[Pete67]

The only thing i can think of is that when the cats on its way out it can produce a sulphur like smell from the exhaust on start up, similar to rotten eggs.

Try a P.M. to Diosnoche and Ragtopcav, if these two can't help you i don't know who can...

[Tweek's Turbos]

Actually they can test the cat. Its called a backpressure test. They blow a hold before the cat, put a pressure gauge in the hole, and run the car. Usually its free at muffler shops.

[gthomp0805]

Well I have not smelled rotten eggs but it does smell rich when I start it and it idles warming up. I will call several shops in the area and see if they will test it and how much it is, if anything. If that does not work I will PM the other 2 guys and go from there. As always gentlement, thank you.

[gthomp0805]

Well I guess in VA things are a lot less exoensive than in NJ. I called a couple of local muffler shops and they all want 90.00 to do a back pressure test. I can buy the tool for 25.00. What a rip.

[earthworm]

A working catalytic will generate about 50 degrees as read by an IR heat gun.
Diosnoche has posted on this subject.
Also the second or downstream oxygen sensor determines if the converter is working..
JC Whitney sold "test pipes" during the 70s........

[suniku55]

This guy just hacked off Cat. I wonder how it runs...
http://www.lehigh.edu/~cak7/Upgrades...atRemoval.html
but he noted on the bottom that don't do this on a naturally aspirated Saab due to the decrease backpressure.

I was shopping for CAT early this year after mine (non-turbo, 160k miles) failed NJ state emssion inspection, Vehicle Inspection generated a report page with two faulty codes - O2 sensor and CAT failure.

I solely trusted the Vehicle Emission Test Report from a fancy new NJ Motor Vehicle Facility funded by criminally-high NJ taxes and began to shop for a new CAT!

http://www.saabcentral.com/forums/sh...ad.php?t=90906
(CAT price and quality is vary as described on the thread. Ebay's $220 CAT seller never replied nor sent the item. I purchased one from thesaabsite.com. My local mechanic said he can get it for around $300.)

It was good time for me since all exhaust pipes including mid pipe was about to be replaced. I replaced O2 Bank1 sensor and CAT and passed NJ emssion test a month later.

[gthomp0805]

I went to inspection back in May, the car ran the same but I failed for the horn not working. Maybe its not the cat but I have had 3 mechanics say it was. None of them could test it other than driving it.