Ok...so I am looking to further upgrade by adding high-flow Cats and headers. I have the Nismo cat-back exhaust already, but I have questions.

I want to replace just the Cats for now, and then wait to replace the headers when I have some more cash. Can I run this setup:

Stock headers > RT HF Cats > Nismo exhaust

I am also concerned about the legality of the RT High-flows. I live in PA, and we have emissions testing here in my county as well. Does anyone know if these Cats are legal?


Thanks.

 

The R/T cats are 50 state legal I beleive. The problem is that the Gov't says you can not replace your factory cats for 50,000 miles or unless damaged beyond repair. I put mine on anyway, since most shops around here will never look under the car to see the cats.

 

To answer your questions:

1. Yes you will have no problems with that setup.
2. I dont remember if rt are emissions friendly. If there not youd have to change them out before emissions or if they are going to pass smog youd prob be ok, cause they usually dont look at the cats anymore.

 

just get test pipesand then when you have to do an inspection put back on the cats. they are easy to swap and test pipes will be cheaper and add more power.

 

Gman, are the test pipes to loud for long drives? Seems like the high flow cats improve power and make a minor increase to the already impressive sound of the Z.

 

Sorry to hijack, but what are some good resonated test pipes?

 

I like my R/T cats. Added some extra power and gave my Z a better sound, plus no rasp. I didn't want go with straight pipes because of the gas smell from the lack of the actual cat. converter, and the R/T cats flow almost as good as straight pipes and are legal.

 

Test pipes will make the car louder but you just have to pick the right exhaust to complement the test pipes....some exhaust are louder than other. A good way to lower the sound from test pipes is to get rosonators on the actual exhaust. I had two rosonators on my old exhaust. This helped keep the noise and rasp down.

 

So are you saying that those cats will pass the sniffer?

 

Yes, they should pass the sniffer. But a visual inspection would probably fail, unless you have over 50,000 miles, they are damaged beyond repair, or the car is over five years old. Most places will not look or do no care as long as it passes smog.Just keep in mind, that the Straight pipes or R/T cats will make your Nismo setup Scream.

 

Ok, 1 more question then. Where is the cheapest place to get the R/T cats? For some reason Performance Nissan doesn't carry 'em anymore.

Thanks!

 

Check the sponsors on this site. I got mine from Performance a year ago. Some people had problems with R/T cats breaking. The thing is, I do not get on the gas until the car is warmed up, and so far I love them.

 

RT cats are not raspy? LOL - not only are they extremely raspy, but also prone to collapse....

 

I said it once and I'll say it again. With my Fujitsubo Legalis R, I have NO rasp at all and After a year NO collapse or any other issues. It was recomended by others to at least let the car warm up before stompin on the gas to let the cats heat up. I do and so far they are GREAT. Best flowing of the cats.

 

So where did you get your R/T cats?

 

I checked every sponsor, and none of them sell them. Only a couple even sell Cats.

 

https://my350z.com/forum/showthread.php?t=120013

 

Like I said, I got mine from Performance Nissan, but they do not sell them. So here are a few that do.
http://www.i-m-racing.com/ratehiflca35.html
http://www.modacar.com/products/Nissan/350Z/MODAHFC/
http://www.tornactive.com/cat_nissan_350z_03up.cfm

 

I had your same concerns...

#16... this is why I chose the HELIX HF Cat specifically
https://my350z.com/forum/intake-exhaust/114798-tp-w-resonators-or-carb-legal-hf-cats_.html

https://my350z.com/forum/intake-exhaust/116664-ts-headers-and-helix-hf-cats-pics.html

Zquicksilver

 

There is a reason why none of the sponsers carry them. They collapse. But if you really want them. PM me and I will send you a link.