Engine swaps and emissions based vehicle inspections

I love my older cars for a lot of reasons but I can't deny that engine technology is making newer motors much better at maximizing HP/ displacement. I was looking at rules for non stock engine swaps and it appears the EPA has some flexibility for this but the pathway is pretty fuzzy and requires proof of equal or better emissions performance that I am unsure how to provide. And even if you could satisfy the EPA, what do you do if your state has yearly testing from the OBD port? Would that test "tattle " that the engine isn't stock? And if so, how would that testing be performed? Anyone on here tried this?

Where do you live, and what are the actual emissions tests in your area?

I live in TN. My Supercoupe's engine is completely worked over--P&P heads, .580 lift cam, half a liter extra displacement, more boost, etc. Passes the sniffer easily with a special engine tune.

My LS1 Camaro is milder, but has headers, tune, intake, all your basic bolt-ons. None of that stuff shows up on the OBD2 test we use here.

Hell, last time I smog tested my MR2 they looked for the catalytic converter under my legs even after I said the engine was behind me. No way they're going to be able to tell a stock engine from a non-stock one. And around here, they wouldn't care anyway.

Outside of California you're probably ok, even there I'm pretty sure you just have to use a newer engine with all it's emissions gear and have it inspected.

FWIW, the EPA rules are more for people who make cars- for your example, companies that do engine swaps and sell for a profit.

Your issues will be far more about your local rules than anything else. Some states have emissions inspections, or even some localities have inspections- but the EPA does not.

If you put a 1998 (OBDII) vette engine into something pre 1990's, they would not even know OF an OBDII port to look at.

I currently live in Atlanta. Not metro Atlanta but right smack dab in the middle atlanta. We have code orange days all the time. Most of the vehicles I own are completely exempt at 25 years old and older. The one I am thinking about swapping is a 1999. Not ancient, but it has been improved on. I don't really want to do add ones as much as swap the engine and ECU for one that is better from the factory. It would also be obd2 but would be modified slightly to remove drive by wire nonsense. Would that kind of thing show up in a port scan?

I am a bit weary of swapping my motor in my integra and using an odb1 ecu incase I do have to do odb2 emissions if I move out of Florida...

In reply to itsarebuild:

If you remove the ETC from a computer that expects one, yes, it will notice that. And I think it will notice far more than a typical emissions code. Ignore the OBDII code reader, the ECU will react very harshly not seeing a controllable electronic throttle, and probably will fault a broken throttle- which will limit power a LOT.

Can you find a swap that does not have ETC?

I live in Virginia, which subjects cars in our dense-est urban areas to emission controls. I also do motor swaps. Here's the CW in the Commonwealth.

The best option is to get a chassis old enough to move into the "exempt" category, which is 25 years here.

Second best option is to rent a parking spot for it out of an emission control jurisdiction; emission control here is based on where the car is garaged.

Third best option is to transfer all the emission controls attached to the donor motor. Then try to convince an inspector that everything is compliant. Around here, for each model and year of autos, they have a guidebook listing what all the stock emission control equipment is, and they will inspect to see if it's there. This is a lot easier with OBD I motors here, because an OBD I inspection consists of a tailpipe sniffer test and running the checklist of required equipment. If you have an OBD II motor, the inspector is supposed to run the OBD II check. It's often hard to integrate the motor swap in a way that makes that possible -- but it's not unheard of.

In a nutshell: http://www2.epa.gov/sites/production/files/documents/engswitch_0.pdf

EPA hasn't changed their policy on this since that time.

itsarebuild wrote: I currently live in Atlanta. Not metro Atlanta but right smack dab in the middle atlanta. We have code orange days all the time. Most of the vehicles I own are completely exempt at 25 years old and older. The one I am thinking about swapping is a 1999. Not ancient, but it has been improved on. I don't really want to do add ones as much as swap the engine and ECU for one that is better from the factory. It would also be obd2 but would be modified slightly to remove drive by wire nonsense. Would that kind of thing show up in a port scan?

Here, the testing would be pretty much just throwing it on a OBD2 code reader and making sure no faults are stored in the computer. If you have all the sensors hooked up from the donor vehicle - including the drive by wire pedal assembly - it ought to work.

Parroting what others have said, pretty state dependent, however you're supposed to bring all the emissions equipment from the newer motor over with it.

When I did the LS swap on my 951 I decided to go through the Emissions Referree process, which was a pretty comprehensive look at the swap. They checked that everything emissions wise was there, that all the readiness codes were set etc. Not only did I need to have emissions stuff, but I also needed an OBD2 port and a working check engine light.

Eventually got everything to their liking and now the car gets tested as a '02 Camaro SS...

The plan would be to swap all the missions equipment. But I'm not interested in drive by wire at all. So if that triggers codes forget it. I'll just modify my motor to the extent I can and move on. Or buy an 87 blazer or something.....

Thanks for all the input!

In reply to itsarebuild:

I would not be worried about the codes removing ETC does- it's the fault reaction that's the problem.

Again, you can keep the ETC, or find an older version that does not have ETC.

Or contact Matt for the correct package of MS.

Most controllers are capable of good enough emissions, so it should be able to pass a sniffer test pretty easy, if that's all that's needed.

Here in Chicago everything OBD2 or newer just has to be clear of OBD2 codes. Anything older is exempt.

95 was the last year for OBD1

Anything pre-OBD2 gets a sniff test at idle and a crappy visual inspection.

A mirror is used to see if the cat has been removed, they never lifted the hood on the last one I did.

Ran on MS2 turbo and had a laptop on the pass seat with Tuner Studio open and running during the "Test".

Passed on the spot. However a few years ago I had to pull the spout jumper on a bone stock fully functional Yamaha Taurus to get it to pass. Testing has since been relaxed because they got caught passing modified cars.

I have no personal experience with this, but it intrigues me. I've heard that certain GM OBD2 ECUs are extremely hackable. Like hackable to the point that you can make it tell the test equipment that it's a different year make and model and SN. And have it ignore thing like downstream O2 sensors and egr. So if you're considering a GM engine, that opens a lot of doors.

In reply to HappyAndy:

If one were so inclined to likely break many under enforced laws, I'd find it hard to believe anybody determined with some C++ skills couldn't make up an OBD2 port simulator program to run on a raspberry pi, forwarding relevant live data (and faking the rest) and everything. Then you could run megasquirt or whatever ECU you wanted. I'd be shocked if such a thing isn't out there already and quietly distributed.

HappyAndy, the VIN# imprinted to the ECU needs to match whatever car you say the engine came out of. That was a huge point when my car got inspected.

Yes, you can use HP Tuners to force several of the readiness codes to always be set, however you still need to have those bits and pieces installed and at least look like they're working. (Or so I've been told....)