Scion tC S-Pipe Question

[Soulbane]

Sorry for all the n00bish questions, just getting familiar with this new set up.

So, there are three sections to the exhaust component to the tC.

From the Exhaust Manifold (headers) to the S-Pipe, to the Tail Pipe.

Meaning, if I have a I/H/E set up, I will still have a necessary restrictive component in my exhaust system.

So with a cat-back system, and headers, I will still have inbetween a restrictive S-Pipe system correct?

Also, what dimensions are best suited to a moderately tuned NA setup?

Intake, LW pulleys, Cat-Back, Headers, and S-Pipe.

Though full 3 inches is ideal on a turbo set up, would 2.5 be more suitable to non F.I. vehicles?

Thanks for all the help, it's really appreciated.

[Speedstar]

Well actually there are 4 sections, but since you are gettting a cat back it wont make a difference.

The S pipe replaces the cat completely. And then the mid pipe goes to the axle back. Like I said since you are getting a cat back...it will just bolt up to the S pipe.

If you get the S pipe, and a HKS high power cat back you shouldnt have to worry about being too restrictive, but you will be loud as all holy heck, and be a little raspy with the header.

Finally, the 2.5" diameter will be fine with your N/A set up. The GENERAL rule of thumbs is for every hundred horse power is equal to one inch. So 300 hp equals 3 inches...

[Soulbane]

Alright, thanks a lot, I appreciate it.

Cat-Back + S-Pipe makes me cat-less at the headers.

Gotchya

[Speedstar]

Correct. Now, please keep in mind if you keeping it legal that you have to have one cat. So if you keep the header then you have one cat, because there is a car right there. If you get rid of both the cat, and the header then you have nothing and you are not legal. I dont know where you are at so that is up to you, but we have inspections here in Virginia.

[bwood87]

Originally Posted by Speedstar

Correct. Now, please keep in mind if you keeping it legal that you have to have one cat. So if you keep the header then you have one cat, because there is a car right there. If you get rid of both the cat, and the header then you have nothing and you are not legal. I dont know where you are at so that is up to you, but we have inspections here in Virginia.

Only removing the first catalytic converter will make you fail inspections (unless you do the CEL eliminator trick). They inspect it by plugging into the OBD2 port. The second O2 sensor is in your s-pipe so its before the second one.

[navylife59]

An to correct an earlier comment, the S-Pipe does NOT contain a catalytic converter. The secondary cat is located at the head of the Mid-Pipe. The S-pipe is usually separate from cat-back kits and only part of one header system that I know of. Yes, the S-Pipe is the most restrictive component after the header. Correctly built S-Pipes do not throw a MIL (Malfunction Indicator Lamp). Replacing the header with one that does not have the primary cat will.
Read about it here in our Tech Article section.

If you do run into a MIL, then you can follow these easy instructions to make and install your own CEL (MIL) elminator.