arethusa71

OK, Another, can it be done thread on engine swaps. Seatching I find a ton of folks who want to upgrade their 987.2 base to a DFI engine. The answer is consistent; BGB. YEAY! It can be done. Well- what about all these 987.1 cars with engines that need replacement? Lots of options out there. But it seems that used engines are harder to find in the covid world. Could one give up some power for some reliability? The 987.2 EFI engine seems to be a reliable candidate, but I cant find anyone who has done this. Yes you would need to source a replacement transmission and drive shafts- which could offset any savings over just getting a rebuilt M97 engine. But I ask the question as I am also interested to see if this has been done. They are both EFI Motronic...

Anyone?

9eight7

I have no idea if this is do-able but it would be significantly more cost effective to sell your .1 and buy a .2 base. There is a really nice one asking for $26k in the market right now.

For $25k +/- I'd rather get a 3.8L than a 2.9L....

sectachrome

Agreed. If you have a .1 that needs a new engine, my guess is that it would be cheaper and easier to get a new M97 built by Flat Six Innovations or the like. I don't think the cost/benefit is there with a 2.9.

ADOR

Worse case I think would be beside the engine and trans combo. (Maybe even the half shafts) would be the wiring and computer.

It would be a given that if you swapped in a 987.2 harness, computer and matching immobilizer from the same car it would work.

If you tried to run the engine with the 987.1 wiring and computer I am not sure how close the sensors are in the newer engine. ( as in sensor type, not location) You would have to see how the variable valve timing is activated and what other input/output sensors work between the two engines.

I haven’t done anything like this on a Porsche as I just got my first one a couple of months ago, but have done and helped friends do several odd swaps over the years.

(Personally I have been curious if the DI 2.7 heads/equipment would fit the 2.9. Then wondering what a 2.7/2.9 hybrid engine would put out. Already know the 3.4 DI is a go in a 2.9 car.)

sectachrome

Oh, that’s an interesting idea! Then again, the 2.7 only makes 10 more hp. Can’t imagine the .2 liters of extra displacement would make a huge difference.
I know that BGBs website says they charge $7500 just for the DFI conversion on .2 base cars.

ADOR

I plan on getting another 987 later on and have been researching 2.5 turbo engine for a swap with a aftermarket computer. Just haven’t been able to find out if the 2.0/2.5 have the same trans as the 987.2 cars. If I did it the 2.5 would be the one I would try out money wise.

The 2.7/2.9 hybrid was just a idea that would only be feasible if you had the time and parts just laying around.

arethusa71

Hey guys- thanks for all the comments. The goal for this would be a low cost solution- it wouldn't cost anywhere near the 25k mark. Keep in mind that the 2.9 is an EFI engine. Not a DFI engine. Also- it runs Motronic 7.8.2 whereas the 987.1 runs Motronic 7.8 - as far as I can tell - pin outs on the ECU are the same. The CPU and memory is faster/larger- but it still is the same language platform. The DFI uses a completely incompatible ECU which is why the swap is so complicated. Note that 987.2 base cars that BGB converts to DFI are easier to convert than a 987.1- but they are still converting the ECU to the new type.

With 2.9 MA1.20 engines being so cheap- It seems that it could be a reasonable solution for a .1 car. The biggest challenge being, yea- how much wiring needs to change. I am still investigating that... I was able to find a pin out diagram for a 7.8 moronic, but didnt find a FULL diagram of the 7.8.2 version. And the second challenge being- that .2 manual transmissions are in short supply. I dont think you would want to take on a PDK transplant too. Soooo could an adaptor plate be fabricated to allow use of the older transmission. hrmmmm....

Its not about selling my cayman because I want a .2 base. I want to see if the solution can be viable, and affordable.

arethusa71

I know someone who was investigating that. But didnt get very far with it.

For that matter, could you swap a 2.9 EFI head onto 3.4 DI or 3.8 DI engine for an easier swap into a 987.2 base.

onespeedpaul

Necro bump on this…. before I go buy a used 2.7L to get my ‘07 cayman base going again, and not really looking to go big 3.4/3.8 whatever, I had found this thread, and put a little spin on the 2.9L idea to essentially just use it as a long block, obviously leaving any sensors/subharnesses that are the same, swapping out any that aren’t, am I crazy? I don’t see why it shouldn’t work.

blackknight530i

Hi there. I haven't done exactly what you're talking about, but I have swapped a DFI 3.4 into my 987.1 Cayman S and I have studied the wiring diagrams, swapped modules, coded said modules, and pretty much everything else involved.

Physically, the engine, transmission and axles should all be swapped and should fit without issues, so long as you use the mounts for the .2 stuff. You'll also likely run into differences in the connection points for the clutch line and power steering lines as they changed from a threaded connection on .1 to a quick disconnect connection on .2. I'm not 100% sure they did this on the EFI cars in .2, but most likely they did. There is also the likelihood that you'll have the same issue I did with the parking brake cable tubes. 987.1 cars had a different bulkhead behind the center console since they had a lot more room on the sides of the engine for the parking brake cables to make big sweeping curves. The engines in 987.2 cars are much wider at the front and require metal tubes for the parking brake cables to guide them all the way to the sides before turning back and these tubes have reliefs cut into the bulkhead so they fit flush. Since 987.1 cars don't have these reliefs, the tubes sit closer to the engine and cause some rattling due to touching the engine and not having mounting studs for them. I plan to cut the relief sections out of my donor car and graft them into my .1 to fix that issue.

You will also likely run into the same issues with the cluster not properly doing the oil level checking without swapping to the .2 cluster and rewiring the oil temp/level wires on the back of the cluster. Since the EFI .2 engine is still a MA1 engine, it still has the same sensors and such that the DFI engine has, so some other modules might still need to be changed to .2 versions. I know that the HVAC module will need to be changed, as well as the PSM module and rate of turn sensor under the center stack. The heater box also needs to be changed due to an added sensor for the evaporator temp, which requires pulling the entire dash (probably the most time consuming and difficult part of the swap) and adding the sensor to the side of the heater box against the front firewall. The CAN gateway module will need to be replaced and the DME and immobilizer module also need to be coded to your car using PIWIS and the programming codes obtained from the dealership.

I'll put it this way, if none of what I have said has scared you away, you'll be fine. If, however, it does seem like it's too daunting, it might not be the best idea to proceed and it becomes clear why not a lot of people do this swap. The wiring is the least complicated part of the swap, especially on an EFI to EFI .2 swap.

I hope this helps.