Blackknight530i 987 GT4 build (981 GT4 engine swap to 987.1 Cayman S)

Hello everyone, I couldn't just leave well enough alone and am about to start another crazy swap in my 2006 Cayman S that has already had a DFI conversion to a 3.4L 987.2 engine. You can read about that process here on the other forum: https://********.com/forums/987-for...um/1400661-blackknight530i-987-1-to-987-2-dfi-conversion-swap-build-thread.html This time I found a really good deal on a somewhat damaged 2016 Cayman GT4 engine that I should be able to repair and since it's a 9A1 engine, swap as a near like for like. Huge shoutout to Randy at DC Automotive in Rocky Mount, NC for giving me a great price on a sub 20k mile engine. Also came with an IPD intake plenum and GT3 throttle body, which is super cool. I won't be able to use it, unfortunately, so it will be for sale soon. This was confirmed to me by Greg at IPD Plenums. They look nearly identical to the 987.2 plenum, but apparently they are different enough that it won't work. Now for the bad part of the engine: Some damage to the valve cover on the passenger side and what appears to be a short in the coil pack after the accident, which fried the wires a bit. I won't be using the 981 wiring harness anyway, so I should be ok. I've already ordered a new valve cover. The good news is 9A1 engines all share the same valve covers and no longer are the cam caps like the old M9x engines, which meant those old ones were matched to the head and needed to be changed together. I found a 2.7L valve cover for $150. It seems that the high pressure fuel pump was pretty damaged in the accident, so I found pieces of its internals sitting in the cam and at the bottom of the head, but I'm pretty sure it fell apart after the engine had already shut down, so I don't think any of it damaged other parts of the engine. Took the broken valve cover off and found some good news. It looks beautiful. No scoring on the cam lobes, everything looks nearly brand new, and only some small aluminum bits at the bottom in some recesses from the valve cover and high pressure fuel pump. Nothing looks like it was sucked into the oil passages and there is no glitter that I can see. The last bit of damage I can find is that the upper mounting boss for the engine mount bracket is broken. I have the broken pieces and I'm hoping I can find a local welder to tig them back on. The good news is that the bolt still goes into some threads on the block, so it shouldn't be too hard to repair. Well, that's all I have for now. This thread will document the swap itself as well as any future mods to help it live up to the GT4 moniker. I know the engine isn't anything more than a 991.1 3.8 engine with a different oil filter housing, but it did come out of an actual GT4 .

Did a bit more disassembly on the engine this weekend and drained the oil. I will send a sample of it to Blackstone to get an idea of where it's at currently. Took the intake off. It's filthy under there, but I plan on cleaning it before it goes in. One thing I didn't realize previously, but makes perfect sense now is that there is no power steering pump on this engine. There is an additional idler pulley where it would be though, so shouldn't be a problem to transfer it over from my 3.4L engine. I knew 981s went to E-PAS, but simply forgot. Also, since I'll be using the 987.2 cooling hoses, thermostat and water pump (pump is the same, but the bracket and such on the block is different), I'll need to remove the entire cooling system bracket on the front of the engine. Part of the reason for this is that I will not be using a 981 manual transmission with the integrated cooling, so I want to make sure I don't have extra cooling pipes that don't go to anything. Intake ports are a little carboned up, but not bad really for a DFI engine. Test fit the replacement valve cover and it's going to work fine. Got it from a 2.7L 987.2, but it's the same part number as the GT4. Top view with wiring harness removed. That's it for now. As I mentioned before, the first several weeks of this build will be prepping the engine and making sure it is good to go. Will continue to remove more parts off of it and cleaning it up. There will be some parts that I will order to avoid needing to remove them from my 3.4L engine. Stay tuned!

Good news everyone! I found a local fabricator that feels confident he can repair the broken mounting boss. I'll be taking it to him hopefully next week sometime. He said it might not be as strong as the original, so if it was damaged by driving it hard or something, it could happen again, but if it was damaged by an accident or improper removal of the engine, it will likely be just fine. I sent him the picture of the car the engine came out of and said I don't think it will fail in the same way again: Somewhere in that pile of parts was a GT4.

Wow that is smashed up! Is that from one accident or multiple ones Do you foresee any clearance issues with the intake on the 3.8 compared to the 3.4?

My understanding was that it was one bad accident. The intake is basically the same as the 987.2 intake, so no issues there. The issues people usually have with 3.8s is that they use the 911 version and don't relocate the oil filter housing so they need to make room to access the filter. Since this is from a Cayman already, I shouldn't have that issue. The exterior of the block is the same as my 3.4, so all mounting locations are the same.

Well, it looks like my fabricator guy was able to fix the broken mounting boss on the engine. Hopefully going to pick it up this weekend. It should be pretty much ready to start doing some resealing and swapping over of parts from my original engine at this point. This was the most worrisome part of the engine and I'm so happy it is fixed now. He also got the broken bolts out where the high pressure fuel pump mounts. So exciting!

bonjour, je viens de parcourir tes deux blogues, et je dois dire que je suis impressionné devant autant de ténacité 😅

ton blogue est vraiment très bien documenté. Pour ma part, je possède également une 987.1 avec 90'000km. Le moteur ne semble pas encore trop atteindre au niveau des cylindres, mais nous connaissons tous l'issue... Je suis également en projet de Track Day avec une puissance visée de 400 -420 PS. J'ai également fait plusieurs recherches pour optimiser le M97/21 sans passer sur un M97/01, mais passer au-delà des 370 PS est un véritable défi autant technique que financier sans parler de la fiabilité😫. En résumé, plus je retourne le sujet et plus je me rend compte que la meilleure solution reste le remplacement du moteur par un GT4 . J'hésite encore entre 2 possibilités : soit un 3.8 (j'ai trouvé un 9A1 club Sport à bon prix, mais pas d'historique, donc frais de remise en état potentiel) ou 2ème possibilité: Je pourrais obtenir un groupe moteur boîte complet et assemblé avec tous les supports moteur de GT4 4.0 9A2 avec seulement 1500km pour 16'000 euro. Il s'agit cert d'un gros investissement, mais quand on y regarde de plus prêt, tout est neuf (embrayage; volant moteur; boîte GT4 avec autobloquant; etc..). comme tu t'en doute, le plus gros défi reste l'électronique 😬, de plus le 9A2 utilise des injecteurs piezo ! De mon côté je suis plutôt parti sur un ECU capable de gérer à la fois la 987.1 et la mécanique GT4 . à ce jour je n'ai pas vraiment trouver de solutions financièrement viables, sauf repasser le moteur en injection indirecte afin de faciliter sa programmation. Syvecs fait bien des ECU capables de gérer un 9A1 (bien que pas tout à fait certain que cela fonctionne en parallèle avec la 987.1 ) mais pas les piezo (je dois encore contrôler si les injecteurs solénoïde du 9A1 se montent sur le 9A2) Link fait aussi des ECU qui pourraient fonctionner, aussi plus raisonnable niveau budget. Bref.. Que penses-tu de mes solutions ?

I had to use Google Translate to figure out what you were asking, but it did a pretty good job. Unless you really want to make it difficult, I would stick with the 981 GT4 engine like I am as it's the same block as the 987.2 engine, so everything can swap over just fine. I should still be able to make 410 HP tuned and have everything in the car continue to work, but keep in mind I've already switched over most modules in my car from 987.1 to 987.2. Apparently, the CAN busses have changed dramatically when going to 981+, so it might not even be possible to make everything work even with the 981 GT4 DME. Since I'm not trying to do that, I'll just be tuning my 987.2 3.4 DME to work with the 3.8L displacement. You could also follow the other GT4 swap thread that another person is doing where they are doing the 4.0 GT4 engine with standalone engine management. If it's a pure track car, I would think that would be fine, but mine will be mostly street and occasional track events.

Hey guys, not a huge update today, but I did finally do the bolt replacement on the cam variators that is preventative maintenance on these GT4 engines if you plan on taking them on track. The procedure is documented here: https://********.com/forums/gt4-spy...orums/gt4-spyder/1188957-9a1-dfi-engine-preventative-maintenance-is-a-must.html . It would be a lot more difficult in the car, so I figured I would do it now while the engine is still on the stand. I also took the oil pan off and looked for any potential debris or other damage and I'm happy to say, it was perfectly clean inside. The oil pan gasket still felt like brand new as well, so I didn't even replace it. Same with the valve cover gaskets. That will make my bill for new parts even lower, so that's cool. That said, everything I was hoping to do to the engine before swapping it is now done, other than swapping over the parts from the current engine onto it (wiring, cooling system, PS pump, etc.), so I think I'm ready to take the car over to get it dynoed prior to the swap. Once the swap is done, I'll get it dynoed again, before and after the tune is loaded. I also picked up a 3rd radiator kit for my car. It's not the GT3 like I had hoped to do along with a GT3 bumper, but it should suffice.

Hey everyone! While this update isn't exactly on the GT4 swap itself, I did want to post the results of my "before" dyno session I got last week. I went to Black Forest Racing in Denver, NC and they did a chassis dyno (Dynapack) on the car as it is and it did very well. The results confirm that it does indeed have a Softronics 3.4 DFI tune on the DME as it produced 295whp/259 ft-lbs, which with a 15% loss calculates to just over 350 crank hp, which is what Scott says it should be. I'd say pretty healthy and will be a great engine for someone after I get the 3.8 swapped in.

Nice results indeed for a 3.4. Is this with OEM intake and headers with cats ?

Hey everyone. I finally got started on the swap this weekend. Dropped the 3.4L out (not too bad a job) in about 4 hours or so with taking our time and lunch somewhere in there. Most time consuming thing was draining the coolant, which just keeps going. Also easy to forget some wires when dropping the engine out. This time I remembered the engine bay exhaust fan and coolant level sensor wiring, but forgot the MAF sensor wiring. No damage, but with most BMWs, the engine wiring harness doesn't have any plugs that leave the engine to go to the body and instead just have a body side harness and an engine harness in the engine bay. Porsche puts all of the wiring on the engine harness and has a few plugs jump across to the body side, so just need to keep that in mind. Next I did the center radiator installation while the coolant was all drained out. Still more coolant drained out of the radiators in the front. Also took the liberty of removing the shrouds and cleaning all the leaves and crap that had built up over the years, including between the condensers and radiators. It was a lot. Then I started transferring over the front and top accessories over from the 3.4 to the 3.8. Still in the process of that and will continue next weekend. Question for anyone that has done a 3.8 DFI swap in their 987, which flywheel and clutch did you use? My understanding is that the crank on the 3.4 and 3.8 is the same and it's just the bore that increases, so I think I'm ok to use the 3.4 flywheel and possibly just upgrade the clutch to the GT4 clutch since it supposedly can handle a bit more torque. I've also considered the 997.2 3.8L clutch and flywheel, but not really sure why they are different than the 987. I could understand the clutch, but why would the flywheel be different? Any help here would be great.

Hey everyone, Got a lot more done on the swap this past weekend. Got everything else swapped over to the new engine and found some more damaged parts in the process. The vacuum pump on the driver side of the engine on the GT4 engine was totally seized, even though it looked like it only took a minor scrape. Glad I needed to swap over my 987.2 one anyway as it was perfectly fine. It was quite a puzzle figuring out where everything goes again and seeing which brackets and such needed to be swapped over. We got everything finally swapped over on Saturday and only had a few minor things to check over on Sunday afternoon, which is when we were going to start reinstallation. We got the old clutch and flywheel installed on the new engine. I know it is used and probably not the best thing to use on a more powerful engine, but it's what I have and I want to make sure the engine works well before I spend a fortune on a new set. The clutch disc had a ton of meat on it still and the flywheel did have some hot-spotting, but never seemed to give me any issues on the old engine. It's not a hard thing to change later, so I'll run with it for now. Dropping the engine and transmission out is sooooo much easier than reinstalling it as it's such a tight fit and getting everything all lined up while lowering the body down on the lift table and hoping you don't crush anything is nerve-wracking. We got it almost totally into the car and realized that we were going to have an issue with the MAF sensor hitting the throttle body on the IPD plenum . When I started this thread, I had planned on keeping the GT4 IPD plenum and GT3 throttle body and making it work with a newly purchased 987.2 elbow tube to put it in the same place as a 987.2 , but unfortunately, there must be something different on the 981 plenum that puts it in a different spot. The MAF and throttle body were very nearly touching each other even without a silicone coupler, the tube was hitting the metal lip around the top access hole, and it turns out the top mounted port is too tall to fit under the 987 engine cover. This meant I would need to either get a 987.2 IPD plenum or go back to the stock plenum. I decided for now to go with the latter. If I decide to change the plenum later, I can try that again. Not ideal, but it is what it is. So now it's just a matter of putting everything back together and filling it with fluids. I may do some of that during the week, but I would imagine I'll actually have it running next weekend. Only about 1 weekend longer than I had originally anticipated, so not bad at all. PS, I can't believe how much coolant this car holds. It just keeps draining whenever I mess with the hoses. I thought I had drained everything, LOL.

Hey everyone, I got the engine fully installed now and it runs great. Initially had me scared that it wouldn't start as I went to turn the key the first time and it just cranked and cranked and cranked, but no start. Checked codes in PIWIS and it was saying High Pressure Fuel pressure too low during starting. No matter how many times I tried to turn the key on to prime it, it would not start. Then, I was looking at the different procedures in PIWIS and found one for First Start under the DME . Tried this procedure, which has you hit start and it seems to run the fuel pump continuously, while starting the car and eventually it came to life. I think all of the air in the fuel system after the high pressure fuel pump caused an air-lock or something and it needed to prime properly. Now it starts every time. The only error code I have is the same one I had when I did my DFI conversion for the fuel pump controller being missing. This is the PWM controller that would have required running an additional wire from the DME to the controller sitting on top of the fuel tank that I just haven't done. It has always run just fine without the controller, so I haven't worried about it. Got the coolant and power steering all topped up and bled the clutch and now it's all put back together. Only issue I'm having is that there is one sensor that is different that I have overlooked. The oil level sensor on the GT4 engine is different than the 987.2 and so while the oil level check on the cluster acts like it is working, it always shows the level too low. I have just realized this, so now I need to swap the sensor over from the other engine. No big deal, but I'll need to drain all of the oil I just put in into a clean receptacle, swap the sensor and refill with the drained oil. Oh well. I hadn't wanted to drive it until I knew the oil level was good, but now I know the issue, so maybe I'll drive it some before swapping the sensor.

Well, I got the oil level sensor swapped. I put a brand new bucket from Lowe's under it and swapped it out Indiana Jones style like @Herbie555 suggested and it worked while only losing about 1.25L of oil. Put that back into some 1L empty bottles and put back in the car. Tested the cluster level check and it was working fine. Now it's filled up with oil correctly. Trying to get rid of some noise from the power steering pump as it seems to be fully filled (actually was overfilled and I removed a ton, but now that I have it at the correct level, it still seems to be making a lot of noise (air in the lines). I'll let everything cool down and check it again, but I don't think I had this much trouble before when I did the DFI conversion. Now the big issue I'm having is that even though I filled the cooling system with the vacuum filler and it took about 5 gallons of coolant, it's got a huge air pocket in the new center radiator I installed. I'm letting it cool down now and will attempt to vacuum fill it again, but that's kind of frustrating. When I did the DFI conversion, I never took apart any lines in the front of the car, other than the center aluminum pipes under the mid-section of the car, so I guess it never had a high spot in the front then. Ugh! The other thing that is annoying is that I think the starter that came on the engine got damaged in the accident as it seems to work most of the time, but sometimes it just clicks and doesn't turn the engine. I wanted to use that starter because it has less than 20k miles on it, but maybe I should have stuck with old faithful. At least it's not the most difficult thing to swap out. Just annoying to have to take that stupid intake off again. That thing is my nemesis, LOL.

Update on the starter situation. I swapped it out, which was a pain, and it still did the same thing. Could not get it to turn over at all. Pulled the spark plugs and then it turned over totally fine. Saw some wetness on cylinder 1 spark plug (passenger side closest to firewall), but the cylinder was mostly dry otherwise (no pools of fuel). Put all of the plugs and coils back in and it started up perfectly and ran fine, all the way up to temp. Coolant seemed to be bled properly this time. Then I let it sit overnight and when I went to start it up this morning, Click! Would not turn over at all again. I ended up pulling the fuel pump fuse again and cylinder 1 spark plug and it turned over totally fine. I could smell fuel a lot when walking over to see Cylinder 1, so I am thinking I have a leaky injector. Below are some pictures of the top of cylinder 1. I looked up the cost to replace just one fuel injector and they are about $763 each!!! They are shared with 991 Carrera S (3.8L) and 981 GT4s. I ended up searching for some used ones as that is an insane price. I found someone selling a whole set for $120 each and bought two of them, just in case. The other spark plugs were all dry and I've tried turning the engine over with all other spark plugs installed and it turns over fine, so I suspect that just 1 cylinder is the issue. On top of that, I kept having a noisy power steering pump, acting like it was low on fluid, but the level in the reservoir said it was fine and actually a bit high. I kept trying to bleed it, but it never got quieter. After doing that last night, I came out this morning and found a huge puddle of CHF-11S on the ground under the steering rack area. Turns out that one or both of the steering lines going into the rack have failed and are leaking a ton of fluid. Now I need to replace those as well. Unfortunately, they are about $350 each and due to size/shape, cost about $250 to ship. I'm hoping someone local to me is parting out a 2009-2012 Cayman, Boxster or 911 so I can pick some up for a lot less than that. Ugh!

Ugh, that's spoiling your enjoyment of the swap now. Have you thought about having the injectors rebuilt? I know from years past that was the go-to for balancing the flow and rebuilding injectors. Could a local hydraulic equipment supplier redo your PS hoses instead?

I don't know of a place that rebuilds DFI injectors, but that would be an option. I'll try the used one first and see if it fixes the issue. I thought about a hydraulic shop and will consider that if the local marketplace guy that's parting out a 911 Turbo doesn't work out. Think is I'm not yet sure where it failed. Connections look a bit different than what I've typically seen, but maybe they can do them.

Just to update everyone, I got the used injectors I bought, replaced the seals (didn't really need to as the old ones looked perfect) and installed one in Cylinder 1 as that was the one with the issue. I bought the Amazon T10133 fuel injector tool kit, which helped to install the new teflon seal, but was otherwise not needed at all as the injectors came out super easy after just unbolting the fuel rail hard line and securing bolts. Also only needed to remove one side of the intake plenum, not the center part that can be a pain to deal with. Unfortunately, I can't check to see if it has fixed the issue yet since the power steering lines are still shot. I just bit the bullet and bought new ones at about $1000 from FCP . Hopefully with their lifetime guarantee, I won't ever need to pay full price for those again. They are supposed to come in Friday, so I'll be able to finally know the swap went well.

Well, Christmas came early and I got the new power steering lines Yesterday instead of Friday. FCP shipped using a new (new to me at least) shipper that shipped it on Sunday and arrived on Tuesday. I didn't even pay extra for shipping. Anyways, got them installed and filled the reservoir and started the car. No leaks from the power steering, but for some reason the pump still makes noise like it's low on fluid. It's not super loud, but not sure what's going on with it. It looks like the fuel injector issue is solved now. Started it yesterday and it started up fine and then tested again today and it didn't have the weird no crank issue it had previously. Will now start on putting everything back together. Power steering pump still makes a bit of noise, but it might be the normal noise it makes as I have the panels removed and when I had them on, it wasn't noticeable. Could be a bad pump I guess. Coolant still seems to be fine. It does stumble a bit at idle, but it might need either an Italian tune up or at least a proper tune. I did reset adaptations and probably just need to drive it around a bit to let it learn. So far I think we're good.

Well, funny story. I put everything back together again and went to start it to take it for a drive and sure enough, CLICK! No crank again. Was about to pull the whole right rear tire and panels off again and pull the spark plug in cylinder 1 to see if it fixed it, but then it dawned on me that I should perhaps check the most important thing I should always make sure is secured when doing an engine swap. The day we installed the engine, I put the engine ground on the stud and the nut over it, to make sure I didn't forget to do it, but totally forgot to tighten it. Tightened it up and now it starts and runs beautifully. Ugh!!! I'm such an idiot. Well, at least it's actually solved now.

Guys, I just drove the car on a bit longer of a drive to fill it up with gas and get to interstate speeds as well a few acceleration pulls and it drives so damn good. The engine is super smooth and the car just overall feels more solid (probably from retightening everything compared to the first swap). It feels pretty much like it did when I first got the car. No smoke out the back, no leaks and the only thing that makes any noise that it shouldn't is I think the power steering pump . I suspect it might be failing as it's full of fluid, but still groans a bit. If I put the windows up though, I can't hear it. I can look at changing that later as for now it works fine. I think the new center radiator does keep it a bit cooler as well. It was out in the rain last night and got a bit of a rinse as well, so while not clean, it is definitely close to clean. Honest feelings about the performance, can't yet notice much of a difference. Maybe after a tune, it will be more noticeable, but I also haven't done any full throttle pulls yet and it's all seat of the pants dyno. It's still an engine with about 60k fewer miles.

Good catch on the bad injector. That new price is painful, used parts for the win. Looking forward to accumulated results. Cheers.