CARBoy

Hi All,

I'm building what we think is the first smog legal LSx conversion in CA, so you can imagine the challenges. It's going into a clean, base, silver 2004 w/ auto tranny. The donor car is a 2006 Pontiac GTO 6.0L (LS2) 6spd (T56) w/ 43k miles that I acquired at auction from Copart. I'm working on the project with Martin at Monster Miata in San Marcos, CA. The PCM (ECU) is an E40, 24 tooth reluctor wheel. All GTO's were 24x. I'm using the BCM and PIM because I hope to retain cruise and AC. This is complicating the build, but it's making the project fun and a great learning experience.

I'll start adding pics and info. Please let me know if there are questions along the way and I'll do my best to answer them.

This is a very exciting project for me. It's been 20 years to get here.

Thanks,
Jon

ToySnakePMC

Jon - Thanks for posting up here. Looking forward to watching this come together. And I can totally relate on the 20 year plan rolling around in your head. Did that as well!

Slmhofy

Did anything ever happen with this build?

CARBoy

Yes! A lot. I'm just a really bad blogger...

2016 was crazy busy, so it's taken longer than expected due to work, a move, selling parts, house remodels, etc, but the build is coming along nicely. We are in the final stretch. Everything is done except some wiring, roll bar, and a few other items. The LS2 runs great, but has yet to be driven. We've taken the time to do things right, so everything is nicely sorted. Due to schedules we only work on it once a week, so we probably still have a couple of months to go.

It's been in a great learning experience and we are going to do another. Having gone through the wiring diagrams for the GTO and Miata in great detail, we have a pretty good understanding of what to do next time.

Thanks for checking in. I'll get some pics up. I also shot a video of the first time we started it. I'll try to get that posted.

Happy New Year!
Jon

CARBoy

Here's the NB when I first got it. And the LS2 as it sat in the salvaged GTO. You can see where the impact pushed the front end in on the left side. Luckily it didn't touch the engine and it ran in the GTO.

CARBoy

Here's the GTO next to the NB with it's engine before the pull. It was pretty clean. Here's the NB engine coming out. I took plenty of photos of both engines and labeled all wires before pulling them. I also shot a video of the Miata engine running, gears shifting, and the gauges working before pulling it so that buyers could see it was in good shape. As a result, it sold for a good price.

CARBoy

We stripped the GTO down to the bare body. When nobody would take that off my hands, we cut it up with a sawzall and put it in a dumpster. It was amazing to fit an entire car in a dumpster. The poor Goat gave up its soul for this project, but the drivetrain fits like a glove (more on that later). I've spent the last 6 months selling GTO and Miata parts on Facebook, Craigslist and Ebay. That's been a part time job itself, but it's paid for the GTO.

CARBoy

Front subframe: Martin is building front subframes. They aren't the pretty tubular type from V8 Roadster/FM, but they are super beefy. After a coat of paint, mine looks great and fits like a glove. Here are the motor mounts and Mast oil pan, which is awesome. The steering rack can now be removed without having to remove the engine. That was a huge benefit during the install and will come in very handy if the steering rack needs replacement down the road. It's now easy to unbolt and drop out. If you use a Mast oil pan, use the dip stick and dip stick tube they list on their website for correct fitment. You can buy them for cheap online. Also, the original capacity of the LS2 is 6.5 quarts. With the Mast it is 5.5. Keep a extra close eye on the oil level as the LS2 is infamous for ceasing due to oil loss.

CARBoy

Exhaust manifolds and cats: For a lot of the country, smog is not a big deal. For CA, it's a major headache. One of the main goals of this project is to build a truly CARB legal LS conversion, registered in CA. A couple of the big hurdles are exhaust manifolds and catalytic converters. The GTO manifolds don't fit in the NB. My donor GTO came with a nice set of JBA's and no cats. The JBA's brought some nice cash that went towards G8 manifolds and thermocoating. I also picked up a set of used G8 mid pipes with the cats. The pipes had to be modified by Martin to fit. Also a few more subframe pics...

Slmhofy

That's great news Jon! I'm actually fairly local; do you think it would be possible for me come come up by the shop some time you and Martin are working on it?

CARBoy

We did most of the work at the shop, but I brought the car to my home about a month ago to finish it. Martin is always happy to show people the shop and discuss Monsters though. Are you planning a conversion?

Slmhofy

I have an 04 MSM and it's an idea I've been toying with for a while. Car actually already has the Getrag diff swap and FlyinMiata V8 sway bar.

Have access to a free 5.3L out of a truck and am wondering if I'll be able to get it past the Referee as long as everything else CARB/SMOG wise is correct.

Was/am really interested to see how far you make it as I'd want my car to be Ref'd and completely legal aswell.

CARBoy

The 5.3 should be '04 or newer, like your NB. Hopefully it has an aluminum block. You might want to scan the threads regarding a 5.3 swap. You should be able to pass ref so long as you use CARB exhaust manifolds and everything else smog related works. I plan to post about my setup. And of course I have yet to pass, so fingers still crossed.

Personally, I'd sell the MSM, buy a regular NB, and put the difference towards the build. An MSM is worth a lot more than a naturally aspirated NB, and it's a bit of a shame to eliminate a real MSM anyway. You can get like $8k+++ for an MSM and an NB is only like $4k+ for a decent one. These are So Cal prices.

zandr

Truck motor is going to be a non-starter. They're different emissions groups, and swapping a truck motor into a car is a no-go.

The important thing to remember with anything CARB is that it doesn't have to make sense, you just have to follow the rules. My experience is that the refs actually want to see this stuff pass if it's done right, and will tell you exactly what "done right" means. (however non-sensical)

The E-Rod in my car gave us a lot of latitude; I'm a little concerned about CARBoy's mix-n-match approach. I haven't been down this road myself, but the information I had was that they'll ask for the donor VIN, and all the emissions-related equipment has to match that VIN.

CARBoy

I'm concerned as well, but Martin assures me it will pass. All parts are LS2 specific.

CARBoy

Yours is a '95 or earlier NA, right? It sounds like the E-rod engine is the way to go, but not for later cars like my '04. It's new territory, but in theory my setup should work. If not, I have a heck of a track car. Lol

zandr

Yeah, mine is a '95, the newest that the E-Rod EO applies to. I also wanted ABS, which means it started out as an automatic, not that it matters.

Good luck, and keep us posted.

-Z

pj_mcgarvey

Interesting take on the subframe and motor mounts. Looks beefy. I'm assuming the steering shaft was attached to confirm no issues with the fit. I did some custom steering rack mounts and they were a b_tch with clearances.

Looks like quality work though.

CARBoy

The steering shaft just clears. It's close, but it works.

Dan_W

Yeah, mine required a slight tweak of the steering column mount to get the shaft to clear the drivers side manifold.

New2miatas

Is that confirmed via referee?? My understanding was that passenger car- 1500 series trucks were one class, while the 2500+ were another class of emissions.

New2miatas

If you don't mind me asking, what are you guys doing for the gas tank?? I think that's often the big hang up with the rules now.

Being in Ca, I'm also watching this thread closely because i'd love to do an LS NB.

BGordon

A question on the exhaust manifolds.
I am doing a 2000 LS1 with 6 speed install in a 2000 Miata (non-California) but really want to use exhaust manifolds rather than headers. Would there be any way to tell if the G8 manifolds would work with the V8 Roadster subframe?

CARBoy

Sorry for the late reply. I'm really bad at blogging.

We are using the stock Miata tank. It's still in the car. Why would that be a smog issue? We have all of the evap equipment, the evap solenoid fires appropriately, and the tank pressure is metered.

CARBoy

Again, sorry for the late reply.

I can't say if they will fit. I'd ask them directly, or FM, post the boards and Google like crazy. I recall Martin saying something about them possibly not working, but I'm not sure. I know they work Martin's subframe, because I have them. They fit well. The mid pipes required a lot of work though, and the current setup is not pretty. The cats hang low. That may be adjusted after smog. BTW, I have nothing but turndown pipes after the mids. It's not too loud, but it's still sitting in the garage. We'll see after I start driving it.