SSmonte

OK I'm in the heart of MA and with the LS2 swap, my plan is to turn the monte back into an emissions compliant vehicle. I was talking to speartech and they are making a LS2 harness that deletes EVAP, AIR, EGR, and the rear O2s. If I were to swap a bone stock LS2, with the front 02s in place, along with 2 brand new highflow cats, it would still be possible to pass the emissions testing correct? The motors burn very clean anyway so I dont see how it wouldnt. The local testing stations have no idea what ot look for so I'm not worried about OBDII compliance, just the emissions part of it.

Basically with cats and nothing else, would the LS2 or any LSx engine pass? Isn't it true that many of the later trucks and cars do not even have AIR and EGR from the factory?

Thanks again
Nick
'88SS

'JustDreamin'

Looking at the MA state emissions testing website, you'd have to pass the Dynamometer treadmill test (IM240). Either way, the emissions standard you have to pass is for the '88 model year.

I'd expect that as long as that motor is in good condition (not down a cylinder or somehting), with 2 functional cats, and a good tune (matched to engine components & modifications if present) that it'd pass. The stuff that Speartech would be deleting shouldn't have that big an impact on emissions performance.

Now if you go and put a wild camshaft and ported heads on there, you might have trouble passing the test. But as long as you're talking about a mostly stock motor, maybe a set of headers and an air filter (you'll probably want some tuning to go with it for optimum performance) you should be ok to pass the test.


And Yes, many of the later vehicles don't have EGR (like the ZO6) or AIR. And the rear O2 sensors are so the OBD system can verify that the Cats are working properly. Since you're not doing OBD, it doesn't need to know.

'Dreamin'

SSmonte

Well since vehicles are coming out of the plants with no EGR and AIR, then I shouldnt have any issues there. But what does the EVAP system actualyl do? I've never really read anyhting on it.

Would the EVAP system affect anything?

Thanks
Nick

G-Body

iTrader: (4)

The EVAP system is for evaporative emissions, to make sure that the vapors from the gas tank are burnt in the engine and do not go into the atmosphere. That is why old cars may have a gasoline smell around them because their gas tanks are vented to the atmosphere. You don`t need the evap stuff to pass emissions because there is no way for them to check if you have it working.....unless they pop the hood. In illinois the only test on your evap system that they do is to test that the gas cap doesn`t leak, so just make sure you use the factory non vented cap and they`ll never know the difference

John B

iTrader: (10)

You'll pass with flying colors. When I first fired up my original LS1 swap I had no AIR or EGR and with CATs I passed the IM240 with flying colors!

For what it's worth, even with the big cam and ported heads I have now I was able to sneak it through emissions again with a little LS1_Edit tweaking and 2 gallons of de-natured alcohol

jasycz28

iTrader: (15)

Do you guys know for sure. Does the emissions go on the year of the car or what kind of engine is in it.

Born-again 7

http://www.torquecentral.com/showthr...t=finally+road

Im not sure of the smog laws in your state, In California your set up would never pass. Here they test the emisions of the new engine not the car it went into. Also removing the evaporative emmisions and the rear o2's will iluminate your check engine light. You have the option of turning that stuff off by reprograming your computer. If they plug into your diagnostic port there going to see the modifications. Check your local laws before you start your project.

'JustDreamin'

That is an absolute must do for anybody looking to swap. Make sure you check with your state & maybe even local government (some states don't have emissions, but certain areas do (like Vegas, I think).

Also, keep in mind, if you ever move, you may run into issues with where you are moving to. Like the Peoples Republik of Kalifornia, for example, where this swap would definitely be illegal.

Here in Maryland, they would test it as a 1988 Monte Carlo. And as long as it passes the test, they don't care what's under the hood (could be a 2000hp gas turbine for all they care). As long as the gas cap passes check and they don't measure too much HC, CO, CO2 (I think its actually a minimum for that one) or NOx, you're golden.

'Dreamin