No Catalytic Converters
 

Hey 370z tuners, I have some questions about tuning. First, when I bought my car, the previous owner had removed the catalytic converters and put Z1 test pipes on the car (I live in the part of Virginia where we don't have emissions tests). Since I have gotten the car, I have put cold air intakes and AAM resonated short tails on the car. So I was looking to get a tune. I have never had a car tuned before, so this was going to be my first experience with the whole thing. I contacted a tuner, and set up an appointment and told them about my setup. They said they could do it. Today they call and say they can't tune a car without catalytic converters because of their policy, and offered to install some for about $1200 or give me a refund. I took the refund.

So my questions are:
Can a car be tuned without catalytic converters?
Am I ruining my car by not having them?
Does anyone know a good tuner on the central East Coast that would tune a car without cats?
If I do get cats, which ones should I get to make the most power?

Thanks!

Smart move on the refund. Most tuners are happy to tune your cat-less car with a disclaimer that the tune is meant for off-road use only. Sounds like someone doesn't want your money lol

Thanks JAR, great info! I appreciate your time and answers!

To follow up with what Jar has stated.

The tuners he recommends are very good. If you're technology competant, you could also reach out to Sebastian from Specialty Z. He does remote tunes. You essentially plug your laptop into the OBD port and collect a data log for him. He tweaks the log and sends it back to you with instructions on what he wants to see. Rinse and repeat a few times. Wala, you have a tuned car.

Jars recommendations on fast intentions pipes are highly respected. Very solid handcrafted work from a very reputable place. Only downdraw is they usually have a decent wait time on fabrication.

Personally, i'd go with HFC's over TP's, but that's just due to the loudness and smell they can give off. Totally your call though. Neither will hurt your car in any way. You may just feel the car is acting sluggish until a tune is done. The ECU's for our cars is very robust at keeping up with bolt-on mods.

Thank you, Leingod! I am not overly confident in my technical skills where car tuning is concerned. I think I would rather take it somewhere and pay a professional for a day. I like your recommendations, thank you for your time!

It is because of the EPA. I suspect more tuners to go this route in the future. The harder the hammer falls the worse it will get.

It is a violation of Federal and state law to remove your catalytic converter. Therefore, my guess is the tuner could be fined under VA law for tuning your car.

I'm not sure if it's a legal thing or not. I can't find any statewide laws for Virginia regarding them except that the inspection book says that if they are repaired they may be welded to the exhaust pipe. I bought my car from Carmax, and took it to the dealer to have it looked over. The dealer told me about my exhaust set up, and I asked if it was going to be a problem with the law or passing inspection, and they said, "No." They passed it this past winter, so it seems like they weren't lying (about passing inspection anyway).

I have a very loud exhaust, and have never been pulled over for it. In fact, I think recently Virginia banned cops from pulling people over for exhaust, tint, lights out, etc. :vuvuzela:

So maybe the law is on my side? Probably not, though.

Either way, I'm looking to get it tuned. I guess sooner rather than later, from the sounds of it.

https://19january2017snapshot.epa.go...hsysrepair.pdf

https://law.lis.virginia.gov/adminco...70/section300/

I had not seen that EPA file before, and it does state you can't remove the cats. The VA law does not say if you can or not.

Just because you don't live in an inspection state doesn't mean you can remove the cats. In Florida you can receive a $2000 fine for doing so!

Agreed, plus,

Federal law supersedes state law every time.

EPA reg states all vehicles built after (iirc) 1968 must have cats if they came with them oe.

Again, iirc, the FEDERAL fine for violating this is around $37k per offense. The EPA has been known to have vans parked along the highways that are equipped with “sniffers” that can get you when/if you drive by. Odds are good that probably won’t happen but it’s out there. Also, any LEO can pull you over in any state if they smell that “catless” odor as probable cause and a quick visual inspection could mean a state level fine but possibly even a federal one depending on your luck.

Long story short, IMO it’s not worth the risk for a street driven car to go catless. ESP when there are federal EPA compliant hfc’s out there. No hfc will meet CARB, but some will meet federal regs. I don’t know if fast intentions hfc fall into that category or not, but they are one of the best companies out there for high quality z parts.

You can go catless until you get caught.

Just want to add one more thing, I was just perusing the latest EPA reg update from December 2020. They reiterated that epa compliant cats are ok, but they’ve tightened regs on OBD tampering. In other words, only afaik carb approved tuning is epa compliant regardless of hfc used.

Example, APR has apr plus carb approved stage 1 tines for many vehicles. Edelbrock has carb approved s/c for Jeeps that includes a locked carb compliant tune. I’m not sure anything like this exists for the 370z.

This is good motivation to pick up a z35 since it’s tt from factory and carb approved stage 1 tuning is pretty easy to get for turbo cars.

Well, I think I'm going to look into getting HFCs, just to be compliant and whatnot. Plus it will probably help resale if I ever sell my car. They should also reduce the rasp in my exhaust tone.

So Fast Intentions is the way to go? The only other exhaust mod I have is AAM Resonated Short Tales. Anyone have this axleback and have an HFC they like?