How many catalytic converters in boxster?

[bigborian]

when i looked under the car i only saw 2 but i've seen from performance parts places that state they make cat-bypass pipes that bypass the secondary cats which mean that they have primary cats as well. Does the boxster have 4 cats? If so where are the primarys? Would the o2 sensors be affected if I gutted the secondary cats?

[mylamb]

It depends on the model year. I believe the older Boxsters had 2. I have a 2001 & it has 4.

[mptoledo]

I have a 2001 "s", any idea of how much power(if any) is lost through the cats? I mean we have no smog testing in my part of ohio, so what the hell!!

[bigborian]

I have a 99 boxster, ic then i will keept he cats since i need to smog all the time damn cali haha.

[mptoledo]

Originally Posted by bigborian

I have a 99 boxster, ic then i will keept he cats since i need to smog all the time damn cali haha.

Picked my Box up in Sanfran a month ago. a lot hotter out there than I thought.


I really would like to know what kind of HP gains I would get by taking off my CATs.
I have googled the subject and haven't found anything. My first car was a 1980 mgb limited, thats when i fell in love with convertibles. The first thing I did was to take off the cat and put headers and a HO webber carb. It really pepped up that little engine. I read a thread about a guy who put a supercharger on his car "OHboxter" I think, But that is a lot of $$ and time. I am just trying to squeeze out every bit of power without jeorpardizing my engine.

[jwade]

get a set of fabspeed by-pass pipes and a bmc air filter. Removing the secondary cats and the air filter really woke up the car. if you have stock exhaust, you could add theirs too or go to an oem tequipment sport exhaust like mine.

i still have stock headers. removal will cause check engine light to come on and i didn't want to spend the 2300 bucks fabspeed charges for the headers. they really need to come down in price if they want to sell more of those. they are nice though.

have fun. i love my car!!!

[mptoledo]

Originally Posted by jwade

get a set of fabspeed by-pass pipes and a bmc air filter. Removing the secondary cats and the air filter really woke up the car. if you have stock exhaust, you could add theirs too or go to an oem tequipment sport exhaust like mine.

i still have stock headers. removal will cause check engine light to come on and i didn't want to spend the 2300 bucks fabspeed charges for the headers. they really need to come down in price if they want to sell more of those. they are nice though.

have fun. i love my car!!!

Thanks for the feedback. yes 2400 bucks does suck. I like the check engine light off too, as I'd like to know if something else goes wrong. I will check into the fabspeed by pass.

Do you get the infamous droning sound? Somebody has a thread(i think 2k3_boxster) about installing an aftermarket exaust and his is dyno checking HP before and after to see if porsche has stiemed airflow. His thinking is that Porsche(companY) might have done this to make the 911 look faster. it is a few threads down from this one, It is a very interesting read and hopefully he will be done soon.

I can't see increasing the air flow through your exhaust will do nothing but good things for your car. More HP better MPG, and less heat. Just my thoughts.

[Adam]

Your car has two sets of cats. One set is integrated with the manifolds and the other is downstream by the muffler which are probably the ones you saw. The bypass pipes delete the 2nd set of cats by the muffler. Here is a pic of the stock system off the car next to fabspeeds pricey system. Use of the cat delete pipes yield about 5-8hp gain typically and a little more sound.





You don't want to elminate the warmup cats or you'll get those CEL issues. Maxpeed makes a more economical set of headers with cats if you don't feel like dropping $2,300 for just the headers alone. They also offer cat bypass pipes and mufflers. If you talk to them about the whole set I believe they offer you a price break.

http://www.maxspeed-motorsports.com/986exhaustparts.html