Alternatives to OEM catalytic converters

[MOWellsinVA]

My 2007 M45 Sport is over 136,000 miles and it looks like one or more of the cats needs replacement. Can anyone recommend non-OEM replacements that keep the near-stock exhaust note and loudness?

[midnightclub619]

i might be interested in this as well. I got a 2007 Infiniti M35x and might be replacing mine. Been looking on ebay but difficult to find CA emission approved cats on there.

[steve_c]

i might be interested in this as well. I got a 2007 Infiniti M35x and might be replacing mine. Been looking on ebay but difficult to find CA emission approved cats on there.

You answered why they cannot be found!
CA emissions (CARB) are tougher then FED standards. Many states have been adopting CA emission standards over the years.
A few years ago, NY adopted CA's CAT standards. It is illegal now in NY & CA to sell & purchase "performance" CAT's, and any other aftermarket CAT's that do not meet the CA standard.
This caused an aftermarket CAT dropout in those states, since those CAT's did not comply with the CA standard.
The CA CAT's are more expensive than the previous ones, and aftermarket producers will have to have their CAT's certified to prove they meet the CA standard. That means $$$!
The aftermarket CAT producers have not caught up yet, but when they do, you will find they will be more expensive then they previously were.
NOTE:
I corrected the above post after checking a website listing Magnaflow CAT's & their emission compliance. It appears the CA CAT standard has only been adopted by NY at this time. Everyone else outside of NY & CA should have no problem finding aftermarket FED emissions approved CAT's!

http://www.hottexhaust.com/pages/find-e ... rters.html

Magnaflow has a CA & NY certified CAT, but it is a universal application!

[EdBwoy]

OP, I haven't seen too many y50 m45 cat replacement threads here. Then m45 main headers have the integrated catalytic converters which makes aftermarket replacement a little tricky.

There were some manifolds on ebay for the earlier m45 for approx $500 each that one member asked about here a while ago, but not sure if they were purchased.

Edit: dec-exhaust-manifold-t600224.html

[MOWellsinVA]

EBay has some of the header/cat design, as well as the Nissan OEM cats. I need to have someone examine the system on my car to find out which cats are bad. It's going to be expensive, that seems clear.

http://www.ebay.com/sch/Infiniti-M45-Ca ... MYear=2007

[MOWellsinVA]

I'm in Virginia so the CA and NY bans won't apply to me.

[steve_c]

I'm in Virginia so the CA and NY bans won't apply to me.

The link I posted shows FED EPA Magnaflow CAT's available by make & model for those not in CA or NY. I see what you guys are saying now, sorry!
Seems like the header/CAT design of the M45 might be the issue!
I thought the M35 & 45's shared the same exhaust system, CAT's & all!

[MOWellsinVA]

These CATCO ones claim to be a direct fit with manifold attached. http://www.catcoglobal.com/part-search.html