Nissan 370Z Forum - HF Cat vs Test pipes on my new Z

Quote:

Originally Posted by Jordo! (Post 3218516)

For max power and minimal rasp you will want resonated test pipes, ideally with long, L or J shaped bung extenders for the secondary O2's.

You may still require a tune to turn off the associated CEL if the ECU sees the primary and secondary O2's matching voltage change rates too closely.

Really, any set will do. If you don't care about rasp or rattle (it is bad, tho'), a set of unresonated TP's from ebay will serve just fine.

That said, if you get TP's, I would consider investing in a tune anyway to improve throttle response, clean up AFR's, and bump up ignition advance.

Or, if you have the coin and either the tools or a shop willing to do it, skip the TP's and go for Long tube headers (and a tune). I recommend PPE.

:iagree: Especially about the "rasp" go resonated!
HFCs are not to bad, but the TP smell doesn't bother me at all.

I finally took off my BERK HFCs because the Connection flanges warped from the heat, (which is a fairly common problem I hear). It caused the CELs to come on a lot and smelled way worse than TPs because the exhaust was leaking right under my seat :icon14: ( I do track some, so your results may vary)

TPs cause less "back pressure" in the exhaust. It lowers your torque a bit, and enhances HP a lot, but it also takes pressure off the exhaust corridor releasing heat better and solving annoying leaks. (at least it did for me)

IMHO, its a very good mod if you push your car like I do. HFCs eventually were very problematic for me and talk about smell!