Boxster Engine Swap---I'm So Screwed

[klink]

Long long story short. I have a 2003 Boxster S with a 2007 Caymen S 3.4 L in it. Shop "1 did the conversion. It will not smog. I took it to shop #2 to get it fixed so it could smog. They spent over ten hours trouble shooting it. Conclusion....it is so hacked up they can't give an estimate for repairs. Could be 10, 40 or even a hundred hours to make it work. What we know... DME is hacked badly (7.8). There are a lot of cut wires everywhere. When forced through drive cycle with diagnostics to wake up monitors the engine starts running badly, and eventually stalls. DME has been re pinned with remaining wires. Sensor polarities have been reversed here and there. ABS and PMS lights are always on. Car runs good driving it. Any thoughts or advice would be sincerely appreciated. Thanks.

[Cajundaddy]

A 987 motor into a 986 is the mother of all can-o-worms. It has been done and I think the shop basically use a 987 DME and harness and matched up the dash so the chassis "believed" it was a 987. A major science project for sure, sorry.

[klink]

Thank you very much for that. That is kind of what I'm being told by shop #2. From the ignition key to the immobilizer to the DME. And then the fun begins. I really appreciate it.

[klink]

Oh, and just for yuks this is the second engine swap from shop #1. First was a 1999 996 3.4 L. That didn't work either. Total time in shop #1 was over four years. Just shoot me. Lol.

[klink]

So, if I may, let me ask this of you all. If this was your car, what options would you consider? Give up and part it out? Find an engine that would be a better match? Put a 3.2 L boxster S engine back in it like I should have done in the first place? Make it a track car, lol? Car is in pretty good shape. At this point I have 20 to $25K in it. Hah! I won't even tell you what other options I'm thinking of are.

[JFP in PA]

Originally Posted by klink

So, if I may, let me ask this of you all. If this was your car, what options would you consider? Give up and part it out? Find an engine that would be a better match? Put a 3.2 L boxster S engine back in it like I should have done in the first place? Make it a track car, lol? Car is in pretty good shape. At this point I have 20 to $25K in it. Hah! I won't even tell you what other options I'm thinking of are.

First of all, these kinds of swaps always end up as a "Frankenstein" build, where the costs go way over center, and the car ends ups being worth less than imagined. Problem is that Porsche has changed both the chassis and the engine significantly with each succeeding model year, making year mix and match swaps a nightmare, particularly in the realm of the electronics. The very early cars had no CAN Bus technology, but in 2001 its deployment began. By the mid 2000's, the car used CAN Bus widely to run most of the system controllers, and by the late 2000's everything was CAN Bus and there were even more individual controllers involved that did not exists in 2003 cars. Even the fuel delivery systems were totally different.

What most people trying your kind of swap end up doing is getting all of the electronics and wire harness from the model year of the engine, and then retrofit all this to the earlier chassis. Not fun, expensive if someone else has to do the work, an you will never get the cost back out of the car as it is one of a kind and no one except the builder knows how to work on it. We had a customer that swapped a Mezger 996 turbo engine into a early Boxster, by the time it was finished, it ended up costing more than a brand new Turbo car would from the dealer. Not for the feint of heart or wallet...........

[klink]

Great comments! Thank you.

[Wayne 962]

JFP is pretty right - except that when done properly by knowledgeable people, the swap can turn out very well. The one we did for the Boxster book is fantastic - car runs super strong, is well balanced, and just passed smog a month ago! Ours was a 2000 Boxster with a 3.4L crate motor from 1999 - very few modifications needed at all (just upgrading the throttle body on the engine to electric from cable-driven).

As I write in my book, the 2003 chassis taking a 2007 motor is doable, but you need to update the ECU and then add some wires for the VarioCam that came out in 2007. Not as straightforward, but still manageable. See the photo from my book below.

As for what I would do? I think that you need to find an experienced shop who can sort this mess out for you and has done this swap before. Riverside may not be the best location for this. I don't think I have any specific recommendations, although Callas Rennsport is the shop that tuned our Boxster when we got everything put back together. We had to install a small resistor on MAF (if I recall correctly) because the flow from the 3.4 was different than the stock 2.7. Small things like these make a difference?

I would also consider taking it back to your garage and doing it yourself - time is on your side with that one...

Hope this helps,

-Wayne

[klink]

Wayne,
Cant thank you enough for getting back to me. I have your 101 projects book and it is great. I can turn a wrench and have a shop with a lift. My problem is my Porsche experience is air cooled, carbs, distributor and such. I just might try stretching myself on this one. Again thank you.
Klink.

[Brian in Tucson]

Originally Posted by klink

Wayne,
Cant thank you enough for getting back to me. I have your 101 projects book and it is great. I can turn a wrench and have a shop with a lift. My problem is my Porsche experience is air cooled, carbs, distributor and such. I just might try stretching myself on this one. Again thank you.
Klink.

Sounds like you're going to learn some new skills. My sympathy! Compounded by the fact you have to live with the infamous CARB.

Maybe you could sell it on to a rural county in CA or out of state somewhere.

I would never try something as radical at putting a totally different engine in my Box. When I did mine, I got an exact same replacement, and it was still right out there on the edge of my current abilities.

Maybe Wayne can mentor you. Nice if you can find someone who's knowledgeable and can help you figure things out. Maybe Raby's in Georgia. The MGR was really quite nice on the phone.

[JJ 911SC]

Originally Posted by klink

... Total time in shop #1 was over four years. Just shoot me. Lol.

No, just shoot them...

[klink]

Lol. I can't shoot them. I hold no grudge. We all have projects that go badly. I still consider him a friend. Quote from Paden in the movie Silvarado. "Might as well treat everybody as a friend or nobody. Doesnt make much difference."

[klink]

Thank you for the comments on selling the car in a non smog area. We've discussed that. It's a good option. If I totally run out of ideas that is what I'll probably do. I'm not quite there yet. These cars are like kids to me. Want the best for them.

[BYprodriver]

Originally Posted by klink

Thank you for the comments on selling the car in a non smog area. We've discussed that. It's a good option. If I totally run out of ideas that is what I'll probably do. I'm not quite there yet. These cars are like kids to me. Want the best for them.

I think you will have to sell it out of CA, 2000 & newer cars are tested to be sure the DME/ computer has not been altered...

[ThinkTank]

i have seen a few 911 never caymans with an LS motor swap that passes smog (ducks)

[laughac]

It sounds cheaper to register it at your vacation home where they don’t check emissions.

[Matt Monson]

I would take the car to Hergesheimer or Vision.