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Hey guys,
My exhaust is not stock and I'm in need of 3" cat. Did a search and found DEC, Walker and Magnaflow but all the results are for 2.5 universal or direct fit. I've searched the web and all require me to input make, model and Year and all this leads to is 2.5 cat.
Does anyone know of any 3" cat preferably Carb legal even tho it's not specific to the 944 turbo? I really do no want to revert back to stock exhaust. Does anyone used 3" universal cat and passed CA emissions?
A 3" cat that may be CARB-legal for another car is not going to be CARB-legal on a 944 turbo.
There is no way around it.
It isn't the part they certify - it is the fitment per car.
The smog guy WILL check the part number on the cat and verify. I have been asked to show receipts showing where I bought it to confirm PN, and I have brought a print-out from the CAT manufacturer's website to prove that the cat on my car is the CA-legal piece.
Make a bolt-in cat section so you can fit the CARB-specific 2.5 cat when needed.
A 3" cat that may be CARB-legal for another car is not going to be CARB-legal on a 944 turbo.
There is no way around it.
It isn't the part they certify - it is the fitment per car.
The smog guy WILL check the part number on the cat and verify. I have been asked to show receipts showing where I bought it to confirm PN, and I have brought a print-out from the CAT manufacturer's website to prove that the cat on my car is the CA-legal piece.
Make a bolt-in cat section so you can fit the CARB-specific 2.5 cat when needed.
Yes I saw your post. I wanted to buy the walker brand. I am considering this option as I do have built on section for my current cat.
A 3" cat that may be CARB-legal for another car is not going to be CARB-legal on a 944 turbo.
There is no way around it.
It isn't the part they certify - it is the fitment per car.
The smog guy WILL check the part number on the cat and verify. I have been asked to show receipts showing where I bought it to confirm PN, and I have brought a print-out from the CAT manufacturer's website to prove that the cat on my car is the CA-legal piece.
Make a bolt-in cat section so you can fit the CARB-specific 2.5 cat when needed.
Yes I saw your post. I wanted to buy the walker brand. I am considering this option as I do have built on section for my current cat.
By definition, if the cat doesn't have a 2.5" inlet and outlet, or isn't placed within 3 inches of the original, or isn't on the CARB list, then it's not technically legal. I have not actually come across a busy smog shop that took the time to confirm that the number on the cat or the pipe diameter is correct, but I'm sure those guys are out there.
Assuming your cat-back section has a 4-bolt square flange like the original muffler, then the easiest route is to just swap in a DEC PO82609B (or PO82609 without the football flange for wastegate dump tube). That cat is 100% legal and works very well when brand new, although it effectiveness seems to go down over time. I have a used spare if needed.
A long time ago, I had the SFR test pipe, which was split in two and allowed you to swap in a cat in place of the rearmost straight pipe. Still have it -- see pictures or it and it's number. It's 3" but pretty old and not legal anymore (since it's 3" and not in same location as stock, and I don't know if the Carb No. survived after they changed the rules). However, when new, it definitely brought the numbers down below the current limits.
If you want to try a near-legal replacement, you could weld in a CARB-legal 3" cat where the factory cat was. The car will pass for sure on the smog test (at least when the cat is new) but if you come across a super strict smog tech, he'd be allowed to fail you since it's 3". Check out summit racing for an endless supply of cats in all sizes, including the CARB-legal Walker CalCat line:
Magnaflow 333009 is a CA legal 3" in/out universal - ~$130. I was looking at having it welded into a 3" exhaust system to see if my local small town smog shop would let slide. That was last March and work has taken over my life so I haven't had a chance to follow thru and get it smogged (and thus even drive the car sadly...). Please let us know how it goes if you decide to go this route.
As Spencer mentions it's not specific to a 944 turbo (it's for Chevy/GMC trucks I believe) but I was hoping that if they did look it up and saw it was universal might let it slide.
The cat MUST have the correct part number for the car, the new Ca smog laws insist on that, and the correct part number is 2.5". 3" cats from a truck are an automatic fail.
I welded adapters to each end of mine, then bolted it (temporarily, it's a track car) in a 3" Lindsey exhaust, and it passed. The cat section can be bolted in as long as the cat is welded at both ends to something.
Paint the front (forward of the cat section) of your illegal 3" exhaust flat black and it will look like a cat-back system to a smog tech looking under a low car with a flashlight.
Thanks for all the response. Yes I'm well aware of the requirements. My exhaust is a full 3" front to back and it was custom made by the previous owner. It's similar to Lindsey's 3" exhaust. Luckily they did this right and placed the cat location right where the old cat used to be. I've been using this unit since 2002 with a 3" cat from Lindsey. Each smog year I bolt them on for that test. This lasted me since 2002 and finally crapped out. This time around I wanted to buy a cat that is CARB legal even if it's not intended for the car.
mtnman82 I hope this asnswers your question. However it does help that I've been going to the same smog tech since 2002.
Tom, long time no talk buddy. Haven't seen you in awhile.
Thanks for the offer to use your spare unit but it won't work on my exhaust. Maybe I should invest in one and keep one just in case for future requirement.
I'm leaning towards the 2.5 Walker Brand that's intended for our cars. I'm wondering if they will be able to expand the inlet/outlet from 2.5 to 3". Anyone have this done before?
01-14-2017, 03:50 PM
3" Catalytic Converter
