Questions about headers and bypass

[root_werks]

Great pictures thank you! That's pretty much what I thought after doing a little more reading up on things. Actually makes putting headers on the 2.5 an easier task than 2.7's and up I guess?

This is turning into a good informational thread on the differences between the early and later Boxsters.

[ChrisZang]

Originally Posted by Stunin_Stud

So technically I can play it safe keep the stock headers and get the bypass for 500 bucks and a muffler and get no CEL and still get a nice sound. how much of a difference in sound or power would headers make? I feel like the headers are all the same and the ones that are not are way to expensive and the power claims seem exaggerated.

Can't talk about the headers, but here's the breakdown for exhaust and bypass:
I have a modded exhaust (no droning and great sound) and added the bypass pipes later
I would say that the exhaust makes 90% of the better sound and the bypass pipes 10% (when reved over 3,500 RPM).

I see you're in San Jose, I work in Santa Clara, let me know if you want to listen to my setup

Edit: Reading your signature I'd guess we already met before

[Stunin_Stud]

Thanks I may get in touch with you to check out your car. Im currently in the caribbean.

[ChrisZang]

Originally Posted by Stunin_Stud

Thanks I may get in touch with you to check out your car. Im currently in the caribbean.

Cool, which island?
I've been to Saba a lot in the last 3 years (like 20 times or so)

[Boxtaboy]

Was thinking about doing the Fabspeed cat bypass pipes on my 01, which has both primary and secondary set of cats. Wondering though- if I get rid of the cats in the rear section and replace with the Fabspeed Cat Bypass pipes, since there are a set of 02 sensors in the rear section as well, wouldn't that set off a CEL light if removed?

[ChrisZang]

Originally Posted by Boxtaboy

Was thinking about doing the Fabspeed cat bypass pipes on my 01, which has both primary and secondary set of cats. Wondering though- if I get rid of the cats in the rear section and replace with the Fabspeed Cat Bypass pipes, since there are a set of 02 sensors in the rear section as well, wouldn't that set off a CEL light if removed?

take a look at where your O2 sensors are and where the cats are on your car and then you have your answer...

[jwade]

Originally Posted by Boxtaboy

Was thinking about doing the Fabspeed cat bypass pipes on my 01, which has both primary and secondary set of cats. Wondering though- if I get rid of the cats in the rear section and replace with the Fabspeed Cat Bypass pipes, since there are a set of 02 sensors in the rear section as well, wouldn't that set off a CEL light if removed?

No it won't set off a CEL if you remove the rear cats and replace with Fabspeed by-pass pipes.

You won't regret your purchase either!!!

[Boxtaboy]

Ok, thanks guys. I presume the rear 02 sensors are located before the secondary cats, and therefore, do not trigger the CEL when the bypass pipes are installed.

[Stunin_Stud]

Originally Posted by ChrisZang

Cool, which island?
I've been to Saba a lot in the last 3 years (like 20 times or so)

Im in Dominica. Im trying to plan out my projects so when I come back to San Jose I can put everything together at once. I currently have the 2003 euro rear bumper being painted along with center console and speedster humps.

[Johnny Danger]

I experimented with several different exhaust configurations before choosing the final system for my 3.2 S. I found the following set-up produced the best results in terms of performance and reliability (keeping my vehicle OBD II compliant).
Here's my ditty:

1. A less restrictive, high quality after -market cat back exhaust.
2. By-passing/deleting the secondary cats (they're like having an extra set of thumbs).
3. Headers and cats that stick with the basic principles of the oem design, however, they incorporate longer, equal length primaries that flow into a merge collector, along with lower cell - high flow cats (something on the order of HJS 200 cell).

No need to relocate O2 sensors, make bungs, chase CEL's, reprogram the ECU, or worry about emissions ! Excellent results in terms of improved power and performance. And perhaps equally important - great sound !

[mikefocke]

damage to your ears over time from the louder sound (and the louder sound system setting)

and

damage to the atmosphere as you add more pollution to it.

Plus I know someone with a dyno who went through dozens of combinations of exhaust component setups before they found a combination that actually gave gains over the entire useful RPM range. It isn't as easy as just taking one from column a and one from column b because their characteristics may cancel each other out.

If I were to want more sound, I'd use Pedro's mod as it is cheap and reversible in a minute by inserting a plug. So if it turns out you don't like it, you can retreat. Or, if you are in an area where such sound is inappropriate (a funeral procession or ...) you can quiet the car to stock.

[eightsandaces]

what about the fabled (perhaps 100% true) notion that these cars need back pressure? I was looking at sport cats and asking around, one guy said he wished he has purchased the 200 cell vs the 100 cell for the back pressure, what't the experience of the header owners??