Confusing Exhaust Question

[TurboDreamzGST]

Ok so I'm looking to put a true turbo back exhaust system on my 98 GST Spyder but I'm a little confused. I bought a Megan racing o2 sensor housing and am ready to buy a megan racing downpipe but will this replace my cat? I was under the impression that all I needed was an o2 sensor housing, downpipe and cat-back exhaust to complete my full straight pipe turbo back exhaust. Is this correct or will I also need a test pipe? Btw I can't afford a full turbo back exhaust system because I'm going to school and on a budget so I'm buying it piece by piece and than having a custom cat back system made by an exhaust shop.

 

[coryf1233]

Your on the right track.. as you know cat-back is litterally from the end of the catalytic converter to your muffler, your downpipe will just replace your stock downpipe, it will bolt up right to your catalytic converter(based on what size you went). Eliminating your cat with a test pipe(if you dont have to worry about emissions) or you can do a high flow catalytic converter..You should feel some good gains from the whole system..

your manifold will be one restriction in your system, 2g mainfolds flow pretty decent in stock form, do some porting to it, and your system will be in good shape

 

[97gst_spyder]

Also, make sure you have all new bolts/nuts. My car has been a Florida car since day one, and all of the exhaust bolts snapped when I was taking them off. Even with PB Blaster.

 

[TurboDreamzGST]

Is there a company that makes a downpipe that will also eliminate the cat rather than having to buy a high flow cat or separate test pipe?

 

[97gst_spyder]

Yes, I know the apexi ones get rid of the cat.

 

[MrBoxx]

The Megan Racing downpipes are cat-delete.

 

[TurboDreamzGST]

so if I got a megan racing or apexi downpipe I would not need to get a test pipe or high flow cat right? There downpipes would eliminate my cat and bolt straight up to the pipe right after my cat right? Just wanna make sure I get this right before I start ordering everything

 

[cfriddle]

The Megan Racing downpipes are cat-delete.

Little more specific? I know for a fact that the apexi down pipe eliminates the cat and bolts right up to my apexi exhaust. The apexi downpipe is really long and the megan racing one doesn't look as long. On my 1g i needed the megan downpipe, megan test pipe, and apexi catback exhaust to complete the system. It seems to me that the 2g's are the same way because megan racing offers a test pipe for them. I ordered one for my apexi setup thinking i would need it and didn't. I think you'll need a test pipe to complete the system

 

[MrBoxx]

It's not so much a "test pipe" as it is an adapter piece that connects their cat-back exhaust to either A: your stock downpipe or B: any 3" downpipe with the correct bolt hole clocking. The adapter piece is only about 3-4" long, and depending on what cat-back you use, either necks down or is simply a straight adpater piece.

As far as I know, all the Megan downpipes for AWD models are cat-delete. I am not sure, however, if all DSM models require the adapter piece for their cat-backs.