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I would say this is an absolute MUST!!! Most will not need my Ultimate options every single Bell and Whistle harness, but Bas will built to suit so that is not an issue. Pretty much plug and play after installing this with the right components.

Jotronic wrote: Sat Sep 21, 2024 12:55 pm Does anyone else have a MaXXecu setup they want to share with the group? I started this thread for others to share info but it turned into a discussion about my setup and I don't even have it yet, lol!

I built a 968 Turbo S/RS replica a few years back and to be able to register the car with the Turbo engine I had to be close to stock with Motronic/AFM etc. I got it registered but layer had issues since the AFM was maxed out and other electrical gremlins on behalf of the old wiring and solderings in the DME and KLR.
Being Swedish Maxx ecu was the way forward since it is produced close to were I live and toners here in Sweden are all very familiar with it.

I started to build a harness with alot of help from friends with alot more knowledge than me on electrics. I wanted all the stock instruments to work so added those funktions into the Maxx harness and in the end everything will be hooked up through the Maxx plugs and the cars footwell plug, the DME connector at the firewall and using relays and safetys at the central electric. I added some extras for the future as flexifuel, sequential ignition etc.
Not done but hope to have it finished in the car in the fall so might get it tuned in the winter.

Tom wrote: Sun Sep 22, 2024 3:08 pm

944m3 wrote: Sun Sep 22, 2024 7:16 am

Bergerac wrote: Sun Sep 22, 2024 6:36 am

I can tell you right now if you used a custom harness for your Maxx ECU and actually used some of its capabilities there would be no comparison in drivability and power. It seems a bit strange to use such a powerful ECU with a stock harness when the cheaper version would achieve the same thing.

Assuming that your stock harness is healthy, what extra capabilities would you have with a custom harness that you wouldn’t have with the stock harness that gives you more power? Sure you might have the ability to add extra sensors like fuel pressure and oil temp, but I wouldn’t think that adds to the drivability or power. Am I missing something?

A bone stock harness would limit you to the AFM, batch-fire injection, stock ignition, etc. -- i.e., pretty much stock with a different ECU. With a custom harness, you can add the necessary hardware to run the ECU in speed-density mode with sequential injection, electronic ignition, etc. -- essentially way more flexibility over what hardware you can use under the hood, and more precise control over fuel and ignition, all of which gives you the opportunity for more power and better drivability if well-tuned.

Im probably in a very good place to confirm this with some evidence. Over the last year Ive gone through 3 phases with my S2 with a 16V Turbo engine about to be installed;

- Stock DME and harness
- Plug and Play Megaquirt ECU with stock harness and AFM delete
- Link Xtremex (Basically the same as the Max ECU - Race) with custom harness with modern injectors, sequential ignition/injection and E-throttle.

The change in drivability at each step has improved the car so much to the point I almost reconsidered if a turbo engine build was a bad choice and cams and ITBs might have been a better choice. Both standalone ECU's have basically had the same tune but since I've replaced the harness the smoothness and responsiveness of the stock engine is unbelievable to what I had with the stock DME. Porsche engineering in the 80s was great but old electronics and wiring are not performing anywhere near 100% and technology has moved on in the last 40 years.

Great information. It’s always good to hear first hand examples.

I’ve been sitting on the pot for a while considering a standalone. Maybe this pushes me over haha

944m3 wrote: Fri Sep 27, 2024 8:48 pm Great information. It’s always good to hear first hand examples.

I’ve been sitting on the pot for a while considering a standalone. Maybe this pushes me over haha

I took the plunge and purchased a MaxxECU race. I purchased the adapter harness, will use stock harness for now. (Fully understand that I should replace old crusty stock harness). Got it mostly for fun and learning. It’s been shipped and I should have it in a couple of weeks.

I’m sure I’ll have plenty of questions along the way but one I have right now, what are folks using to capture oil pressure? I believe MaxxECU can’t use stock pressure sensor but I could be wrong. Want to be able to set safety limits around oil pressure.

Will add, @Jotronic I have same setup as you minus the new fuel rail. Will be fun to compare notes once running In my case should be running by end of January.

Following post. Interested in the MaxxECU as well. Thanks for posting on your project.

Per the vendor, this:

https://ems-shop.se/en/article.php?id=4 ... =185063759

Paired with this:

https://www.lindseyracing.com/LR/Parts/944OILADAPT.html

You keep the stock dashboard meter and add oil temp and pressure to ECU. This allows you to then set safety measures in case of low oil pressure.

Jotronic wrote: Sat Sep 21, 2024 12:55 pm Does anyone else have a MaXXecu setup they want to share with the group? I started this thread for others to share info but it turned into a discussion about my setup and I don't even have it yet, lol!

I started a separate thread but will bring my questions here.

After finding some time, finally got the car running with stable idle using the adapter harness for MaxxECU. Unfortunately when I rev it I get sync errors. Rather than trying to fix it, I installed a 36-1 wheel at the front with a VR sensor. Now waiting for the shielded wire so that I can connect to ECU.

While I wait, I’m studying up on configuring the 36-1 trigger on the ECU. Learning curve for sure. And surprisingly little examples online.

That being said, will bump the original question, does anyone have a tune for Macxxecu to share. I’m kinda just interested in what the configuration of the inputs look like, especially for the trigger and home inputs.

Btw I’ve only idled the car in the garage. Have not driven it out yet.

PS I know I should get a new custom harness. It’s on the list for sure. For now just want to get the car drivable…and keep learning.

944m3 wrote: Thu Dec 26, 2024 12:16 pm

944m3 wrote: Fri Sep 27, 2024 8:48 pm Great information. It’s always good to hear first hand examples.

I’ve been sitting on the pot for a while considering a standalone. Maybe this pushes me over haha

I took the plunge and purchased a MaxxECU race. I purchased the adapter harness, will use stock harness for now. (Fully understand that I should replace old crusty stock harness). Got it mostly for fun and learning. It’s been shipped and I should have it in a couple of weeks.

I’m sure I’ll have plenty of questions along the way but one I have right now, what are folks using to capture oil pressure? I believe MaxxECU can’t use stock pressure sensor but I could be wrong. Want to be able to set safety limits around oil pressure.

Will add, @Jotronic I have same setup as you minus the new fuel rail. Will be fun to compare notes once running In my case should be running by end of January.

Sorry for being absent from my own thread, and your posts:) So here is the update on my build. It has been a Hell of a ride and, knowing what I know now, I would have just built a new motor and had a new harness made from Bas, or now from Kroon, for my MaxxECU Race.

To recap:
I got a little ambitious with my stock motor that has almost 150K miles. I thought a little more power with some bolt ons would be a simple affair and I'd enjoy the small boost in performance while I get a new motor built. I also thought I'd take the time to do some A/B testing between a set of chips and MaXXECU to help add some evidence to the argument, pro or con, for whatever it would be worth. First step in that brilliant idea was to get a new OEM style harness from Kroon. Great guys to deal with, fast turn around on a fresh order and it is a great product. I highly recommend these guys. This would allow me to use my Focus 9 Tech DME with OBD and some new chips. I decided to try a set from John Behe, the old racer in Maryland. I forgot how I learned of him but he would work with me to get the right tune if his original set didn't make me happy. He said once I had a dyno sheet for him he'd be able to dial it in with the second chip. Then, I'd simply use the harness and MaxxECU from Drivestore.se and do an A/B comparison.

My build. I ordered the RaptorX from Charlie and had a shop on Ebay I bought a used K26 from ship it directly to him. I had my new RaptorX in two weeks. I ordered the full 3" Fabspeed setup with 200 cel Sport cat as well as a 3" downpipe. Got the Tial F38 and adapter plate, and from Tim at SFR I ordered the Stage 2 4 into 1 header, which is a piece of art, Stage 1.5 intercooler which is as well very nicely made, accompanying intercooler pipes and intake. I wrapped the headers (will NEVER do that again) in DEI header wrap. I also ordered the crank mount 36-1 trigger wheel from 928-944parts.com where they pre-weld the trigger wheel onto a pulley wheel for you. Outstanding! Got a new front timing chain cover setup, the Nissan alternator mod, Lindsey Racing 3X oil cooler kit (this thing is awesome!) and every sensor in the engine bay was replaced as well. When it came time to install the new headers, it was discovered that one of the manifold bolts had to be retapped into the head by a previous owner and they went in at the wrong angle, hit a water passage, and simply patched it with silicon. Worked pretty damned good apparently since I had no problems for the two years (up to then) that I owned the car and it survived the initial 12 hour drive home when I bought it. Got a new refurbished head from Tim at SFR and that was that. So many little problems here and there getting it together that I can't begin to document it all. The problems came to a head a few weeks ago when I had the car home, after what I thought was the last time it would be at the shop for this build, and I was prepping to drive to Southern Cal for a Porsche Rally. The night before the event, I washed my car and was going for a quick spin to dry it off when i noticed smoke coming out of the engine bay. Fire. Oil had leaked badly from the cam cover and onto my header wrap. Luckily I had my extinguisher and put it out before any damage was done. Back to the shop.

F my life.

Technician error from not torquing down one of the bolts, like at all, because the damn thing was missing! Needless to say it was dismantled and put back together at no charge along with some new coolant hoses. I love my shop and they've become like a second family to me (I was there every other day for eight months) but from now on, only the owner is touching my car, no underlings.

The outcome?
The chips from John Behe were trash. The car wouldn't even start up. In fact, the stock chips fired the car up just fine. With some spotty communication from John, I decided to ditch the idea of A/B testing since I didn't want to wait two weeks in between chip testing, not to mention dyno time in British Columbia costs entirely too much money. I told John I was ditching his chips and what I thought and he didn't even bother replying, much less offering anything resembling even a partial refund.

Enter MaxxECU and the harness. It wasn't church bells and rose petals getting the thing to run right. The base tunes from Drivestore got the car running but the 300hp tune was trash. We had to play with it a lot to get it running. I then used some guy recommended to me by a 944 specialist who is based in the mid-west somewhere and does remote tuning. He was way too arrogant and kept trying to push my turbo to 17psi after I told him three times I wanted a conservative tune since my bottom end was old and unopened with a lot of miles. He got it to open up a bit more but he had the timing dangerously advanced and it was clear to me he had no idea what he was doing with my car. Connection severed. More money wasted. My mechanic and I dialled it back down to something safer. Drivestore guys were a mixed bag. Erik was cool, very patient with me, and understanding and helpful. I like him. His partner Thor is a dick. Impatient and even insulting. He made some derogatory comments to me when I was trying to grasp what he was trying to explain which he then deleted in our Whatsapp conversation quickly thereafter. I gave up dealing with them altogether. A few weeks ago I finally got some dyno time. Again, the goal was more power but conservative. My mechanic and I decided to go no higher than 13 psi just to make it fun and keep it safe. We wound up at 14psi.
Yes, it is not a lot of power given the mods I have. We could go to 17 to 18 psi and the car would be transformed but it might also grenade on me. Everything that can be bolted on to make more power has been bolted on. Every sensor, new harness, etc. etc. It all started out with just wanting "some" parts bolted on but it seemed like every new part bolted on revealed something else that needed to be done, be it a modification to make the new part fit (SFR crossover, meets Tial F38, meets Fabspeed Sport Cat = custom welding job) or replacing something I didn't plan on replacing because it was literally broken (cylinder head) and everything that goes along with it. The motor isn't in top shape with some cylinder scoring. Here are the numbers before it was in the shop for the bolt ons.

Numbers from a year ago before the modding started on the motor.

Compression Test: Leak down Test
Cylinder #1: 135 PSI Cylinder #1: 6%
Cylinder #2: 135 PSI Cylinder #2: 4%
Cylinder #3: 135 PSI Cylinder #3: 8%
Cylinder #4: 140 PSI Cylinder #4: 4%

So yeah, good times. It is not hyperbole to say I could have bought a 996TT for what I've spent on this car since I bought it (yes, including the original purchase price). Granted, I do have 996TT brakes, Intrax suspension with Elephant Racing bushings, Wavetrac LSD, transaxle resealing, basically everything under the car is new, and so much more. I mean, I don't cheap out when it comes to parts, but I don't have a garage to turn a wrench for the bigger things so a lot of what I spent is in labour too.

Knowing what I know now, I would not have started any different. I got my suspension sorted first, then my brakes to prep for the motor work. But, I would have ignored my stock motor and had a separate one built fresh, ready to handle bigger power. I would stick with MaxxECU and a new custom harness from Bas or now from Kroon with Bas's guidance on their MaxxECU offering. Then, just drop my current motor and lift up the new one and go. It would have been about half the cost and double the reliability and nearly double the power. As it stands, I have a 16V S2 motor that I'm sending to Blackbird Technical Services in Calgary, Alberta to build into a 500hp monster. 01E conversion kit with chromoly axles will be here any day from Lobb LTD and I'm working with Peter from Drivesport.ca to build a fresh 01E with custom gearing.

As the car stands now, I drove it home from the shop on June 3rd and it sat for several days as I just didn't want to drive it. I was deflated from the entire affaire. I got a wild hair and before I got the car to the shop after the fire I decided it was time to install my Lutz Auto PCB and LED bulb setup for my gauges. Once done...my fuel gauge doesn't work and my airbag and emergency lights won't turn off after the car starts. Such fun. Lutz Auto hasn't been of any real help. The airgat light and emergency light is probably due to needing an airbag reset, which I'll try, but the fuel gauge issue I'm unsure about. And as for my headers, I will never wrap them again. I had them cerakote treated in glacier black and I'm pretty happy with them so far. Over the weekend I got the car out twice and enjoyed it, albeit for only a short jaunt to the grocery and and then for a slightly longer jaunt out to near my local airport just for the joy of it. The torque, as you can see from the graph, is pretty flat and comes on early and the car feels completely different. The turbo lag is nearly gone, or feels like it, and the power comes on very smoothly. I'm slowly starting to love my car again.

This was not only an uddate, but a chance to vent a little, lol!

@Jotronic

Dismaying to read about the trials and tribulations you've been through, but someday you may be able to look back at the experience with a knowing, wry smile.

Meanwhile, such a great-looking car! Good pics too.