'99 Test pipes
#1
Track Day
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Join Date: Jan 2002
Location: Fresno, California
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My brother has a black '99 that bought new in Germany with out cats!!!. Even with the stock muffler it sounds mean...(Has aftermarket headers, also. Cargraphics they sell 100 cell cat's, but what about test pipes, staight bypass tubes that replace the converters? I already have the headers. Does anyone have any info? Thanks! <img src="graemlins/beerchug.gif" border="0" alt="[cheers]" />
#3
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If you replace the cats altogether, then the O2 sensors won't read correctly and your engine won't run right, plain and simple. Unless you disable the computer's ability to tune the engine by reprogramming the ECU to ignore the O2 sensors, you are asking for trouble, and check engine lights...
#4
Track Day
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It is a stock 2.5L. The test pipe has a provision for the O2 sensor. Kinda like the 3.0sc motor. He has never had any check engine lights. I will talk to him over the weekend and ask him for more info. In my old sc I had a test pipe. I removed it every 2 years for an hour, to have the car smoged and then I put it back on. I had a SS Dansk muffler and the sound was unreal...
Have you guys seen noticable difference with the headers? What about muffler and ECU mod/upgrade? Who would you pick for an ECU upgrade? Since I am new to this so I could use some help...
Stavros
Have you guys seen noticable difference with the headers? What about muffler and ECU mod/upgrade? Who would you pick for an ECU upgrade? Since I am new to this so I could use some help...
Stavros
#5
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The 2.5L is different from the 3.2L setup that has 2 O2 sensors on either side of the exhaust and if they don't have a difference between them (meaning a cat of some type) then the check engine light will come on. The computer constantly readjusts the fuel/air mixture based on the readings from the MAF and the O2 sensors as well as the performance of the engine, if you remove O2 sensors or give them readings outside of their design tolerances then performance will be affected.
For ECU reprogramming I like Gunther's program based on TTP work available from Paris Audio in Los Angeles. I don't know if he has a 2.5L program or not.
Headers are a good thing on the 3.2L, I don't know how much difference they make on a 2.5. Dyno charts are on my website of my setup in the Pictorials section.
<a href="http://www.smiley.net/boxster/" target="_blank">http://www.smiley.net/boxster/</a>
For ECU reprogramming I like Gunther's program based on TTP work available from Paris Audio in Los Angeles. I don't know if he has a 2.5L program or not.
Headers are a good thing on the 3.2L, I don't know how much difference they make on a 2.5. Dyno charts are on my website of my setup in the Pictorials section.
<a href="http://www.smiley.net/boxster/" target="_blank">http://www.smiley.net/boxster/</a>
#6
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Guenther says that ECU and headers are pretty much worthless on a 2.5L.....2.5L headers infact are much more free flowing that 3.2L headers and PAG advanced the 2.5L ECU alot