Thread: Catalytic Converter Questions!!!

So basically, my car needs a new Catalytic Converter. The question is, which cat to get and would i need to do any tuning if I get a cat other than a stock type replacement?

I'm looking at getting the PFYC.com High Flow Catalytic Converter with the 3'' inlet and 2.5'' outlet. Has anyone bought one of these before and would I need to do any tuning to the car to make it work? I don't have any tuning software/hardware so I want to be sure that whatever I buy would work by just installing it.

Any help with is appreciated. Also any advice for other possible replacements is good to. I'd prefer the cat to work the same, or better with no computer modifications needed. Thanks for the help!!

magnaflow make's the best high flow's i think

Changing the downpipes and such was just an option from a prefab part. Mostly now I'm looking into a directly welded MagnaFlow Catalytic Converter. My problem so far has been finding the correct one to get. There are sooo many different models. Double check, the 2004 GPs like mine are 2.25'' in/out pipes right?

Has anyone actually gotten a MagnaFlow Cat for a GP similar to mine? It is a little difficult to look for the different types of cats available from this company and I have yet to do measurements of my current cat to get some idea for how big the new one should be.

Likely it will throw a P0420 code if it's a high flow.

Also..your exhaust isn't 3" so that may be a problem fitting a 3" inlet and 2.5" outlet into.

Originally Posted by BillBoost37

Likely it will throw a P0420 code if it's a high flow.

I'm already getting the P0420 code because the cat has issues.

If your signature is still up to date, the factory exhaust pipe is 2.25"...get that.

You can get a Magnaflow High Flow off of EBay for way cheaper that way.

And...still throw a code

Originally Posted by BillBoost37

And...still throw a code

YEz.

And...still throw a code. Not a question, a statement.

I know,

I was meerly agreeing with your brain.

I agree ...too

OK, so what would get rid of the code? Would the computer have to be tuned some for the new cat?

I remembered I don't have a 3'' inlet, but I believe the PFYC.com is supposed to fit directly on to increase the downpipe size. Not sure though. I'll look into magnaflow, but finding a way around the code problem is important.

Tuning could take care of it.

Just get a catted 3" bolt-in downpipe and have someone tune it locally...I'm sure there is a Florida Grand Prix following...

Southeast At Your grandprixforums.net

I'm attempting to limit my car downtime and not have to spend a bunch of money. That's why I'm trying to get a replacement that wouldn't need tuning yet may still give some benefits.

Just get a 3" catted bolt in downpipe then?

And have a local tune it.

There would be no down time.

Or replace with a stock equivalent that's going to meet the pcm requirements and be done.

Yeah, right now the estimate from my repair shop is $441.29 for the cat. Which seems very high if it's just a replacement part. The high flow cat from PFYC.com was $471.05 so if I did that, increase the downpipe size and have the repair shop just do a tune to make the engine work correctly, it may cost around the same as the original cost with a higher performance part.

I guess I just have to see if the downpipe change and such would work correctly.