Im thinking about doing a ls1 swap into a 92 z28. Hows the whole smog thing work here in Cali? Just want to see what others have done here so Im legal before I buy a 4th gen donor car

 

You can only swap a newer motor into an older chassis of the same "class"; car motor into car yes, truck motor into car no. All "emissions devices" for the later motor must be in place and operating. for most situations that would include the gas tank. Often the newer transmission has to be swapped too. Car must pass smog for the year of the motor, not the year of the car.

In general, a well-done LSx swap is a slam dunk.

 

My concern is the exhaust since an ls1 uses 2 cats anf I see most running long tube headers which wont pass visual do the stock manifolds clear. Anybody done it here in Socal? Would love to see one in person

 

And very expensive if done right to get by the referee.

There is no cheap way out.

 

Moneys is not an issue.

 

'01-'02 Z28 exhaust manifolds fit well, if you move the left O2 out of the manifold. For dual cats just copy the '89-up B2L arrangement, but the CA-legal OBD2 ULEV cats are around $400 ea.
I recall reading that a GTO's GM CAI fits well and passed Cali req's.
You'll need the '00-'02 tank, evap, sensors, etc. I'm finding it a hassle to retrofit the fuel tank pressure sensor into my third gen tank.
I don't have to meet Cali req's yet, but I really want mine to meet ULEV standards. So I've done lots of research.
If cost is no object, why not just do Chevy's E-Rod LS3 crate conversion? That's Cali-legal, much more power, and Turbonetics offers a Cali-legal turbo kit for the LS3.
Then while you're at it, back it with a new T56 Magnum. Or a new 4L65E.

 

I spoke to a California smog ref on friday. All the smog equipment from the year car must be used and the cats can only be moved a maximum of 6 inches from the stock location. O now Im investigating if the ls1 stock manifolds and cats will fit along side the trans and still give enough ground clearance.

 

I already explained the exhaust manifold situation, there's no tucking the cats the way you propose. Go explain to the guy, show him what does fit, explain that ceramic wrap will keep enough heat in to let my way work. The idea is to get the cats hot enough quickly enough after a cold start. Using the '98-'99 manifolds would allow 2.25" downpipes to the cats, rather than 2.5", and that would help light off the cats. I have a pair of those manifolds also, for my S-10 swap, but haven't test-fitted them in my '86 Camaro. Yet.

 

I have an Ls1 swapped Iroc I am going to try to get reffed... I have a couple new Ls2 GTO cats I got from my uncles Ls2 Rx7 swap... can I use them in my Ls1 Swap so I don't have to buy the CA-legal OBD2 ULEV cats?

 

You better take the papers that came with those cats to the ref before welding those cats in. If they came from a crashed GTO, then no papers, so probably no pass.

 

That is a bummer! I can't just borrow cats from someone else? Do the cats have to be registered to the vin number or something? How are they going to know?

 

What do you care, when you just told us cost is no object? Do it right, be done with it, no more stress.

 

What the law says is "it is illegal to sell or install used cats for a car or truck"
So, no way to get that by a ref.

 

That's what I'm trying to figure out. What the legal way is. I myself like to do things right the first time. This is why I'm asking what others have done before so I get it right the first time. As it is right now the only snag is the cats fitting withing 6 inches of its stock location from the donor car. New cats for the year car or the ones from the donor can only be used. So gto or corvette ones are not useable in California according to the ref.

 

I'm pretty sure you can use the Magnaflow 46705. The convertor is on the Cali approved list for the LS1. ~$450 for the pair.

You need to figure out how to get them mounted as close to the manifolds as possible.

You can make an appointment with the ref to discuss these issues. There will be no surprises if you talk directly with them.

 

I am doing this swap now. I will be dropping in the LS1 and T-56 in two weeks so i will see soon if they fit or not. I am sure they will as it has been done many times by members here on this forum. I also disagree that it is expensive. I have not completely itemized, but I can tell you I got my engine off craigslist with cats y-pipe radiator all accessories (90K miles) For 1300.00. Junkyard 97 T-56 150.00. Conversion kit, input shaft 150.00 front plate 175.00 bell housing 225.00 clutch 300.00 slave 75.00. Entire 91Z28 w/TPI305 700.00. The little stuff adds up but I am in it for under 3500.00 so far. I am not done yet, but I'm well on my way. You don't need to through money at your project if you take your time and look for the bargains. If you want to push it through it will be more expensive and I advise you to just get a wrecked swap car as you will save money in the long run.

 

How about the fuel tank with charcoal canister? The stock thirdgen has to be replaced by the one from the donor car as well.

 

yes i have the 4th gen fuel tank and stock fuel lines. I am trying to use as much 4th gen stuff as possible including the complete wiring harness interior as well as engine harness 4th gen rear end as well as complete interior.

 

I found your thread I'm following it now and will like to cruise down some time and see the engine in and hooked up once its done

 

One big issue seems to be getting the fuel gauge to work properly.If not the Evap system will not function as intended.Which is a fail w/ the referee.Far as I know, no one has gotten it to work.Some just swap the whole cluster (or dash) from the 4th gen, since the associated wiring is integrated with dash/gauges, etc.

BTW, how are you guys getting in contact with a ref? Is there a number or address to go to?

 

The gas gauge has been adressed. You can change the sweeper unit in the tank to match a third gens cluster. Google California air resource board referee. They have numbers to call for your area.

 

The computer uses ohm reference from the fuel gauge (& other sensors) to determine when to purge the tank.The sender swap only fixes the gauge (mostly).It doesn't fix signal to the computer, because the ohm range is different than what the comp is programmed to look for.

From what ive read, it wont set a CEL, but it will store a code & the ref will find it when they check the system.The Evap will still function, but in a default mode of sorts, in order to purge the tank, but the code will be set regardless.

Ive read a lot of the threads on this & no one ever got one working as OE.Most guys have either removed the Evap or left it in default mode, but those were not Ca, 3rd gens.So they have it easier than us.Ive read some San Diego guys have done it, but no idea who they are.Maybe one will chime in.

 

Gotcha

 

Is there a way to update the PCM to read the 3rd gen range for the purge? Or is that not in an area that is able to be modified? My other idea would be to piggy back both senders on the arm, with wires going to the PCM and dash, respectively.

 

Ive not read of anyone doing that.Doesnt mean it cant be done or if it wouldn't work.There are people here more knowledgeable than me on this matter though.

 

If you search for it there is a writeup on how to modify the stock gauge to read the 4th gen signal and then the computer ishould be able to have the correct input from the tank.

 

If you're going to go smog legal I'd suggest to get a donor car. Here in L.A. people charge 4-5k to do a smog legal swap.

 

Who can I contact in LA to do the swap for me? Not too bad a price to avoid all the hastle...

Mike