robflying

I'm a gear head, been a gear head all my adult life. New to water cool Porsches, But I did own a 71' model S fun car. Been modding many different car. Just purchased a 2003 996 that had a 3.6 normally aspirated engine. Lady luck is on my side and I was able to purchase a good 3.6 turbo engine. The question is this. I don't see why, maybe someone can explain. can the regular ECU be mapped to work with the turbo engine. I see it as a tuning thing but not being an expert, I rather check on the subject. Tried doing searches but nothing found. Maybe this is the first ever.

Paul Waterloo

How do you map a NA engine ECU to a turbo set up? It doesn't know what the boost is, it can't rely on the O2 sensors...it will be too late.

It would be so much easier and cheaper to buy a 996 turbo. Or buy the one supercharger kit for your NA motor.

Happy New Year!

robflying

Okay so let me understand. So TCP racing or vivid racing use a different ECU for their turbo kits? Maybe it does but I don't think so. Its mass air mapping, curve timing, ignition curving regardless of the turbos. There isn't any harness going to the turbos as far I can tell. With any other engine I've ever seen curving of the computer call tuning. is done via a laptop.

Paul Waterloo

How are you going to measure boost and insert it into the ECU? I do have a 944 turbo, and I have a piggy back fueling system.....it not only looks at everything a normally aspirated engine does, but it also looks and boost and has a map for it. Here is a picture of the piggy back map....it was writing to the ECU after I changed values based on my air fuel ratios.

The normally aspirated 996 does not measure boost not does the ECU care about this function. I have never seen a normally aspirated 996 that had a turbo on it....it might exist but I've never seen one.

robflying

I see and understand what you are saying truly. TCP and Vivid make turbo packages for the 3.4 and 3.6 engine, keep in mind these engines run very low boost nothing over 5 psi. At least from my reading, unfortunately their site don't give out too much info. They don't offer a piggy back or replacement ECU. that why I'm stating such statements.

Turbojamie

Why not just use a turbo ecu?

robflying

Because like Paul can tell. try finding one, oh and get ready. They will want your first born and kidneys to boot.

robflying

All ECU's measure air. What is boost high volume, high pressure air. It is still measurable. A piggy back maybe the ticket.

strathconaman

Talk to pete95zhn. He has done this, and the results are spectacular.

lowpue

I would talk to Charles Dundon in Gig Harbor, WA (Dundon Motorsports). He is an engine genius and probably one of the best in the Northwest. He just put a 997S 3.8 into my 2000 996. He did the harness rewiring, added variocam and a whole bunch of other functions. He is the nicest guy...just call him and tell him the guy with the yellow C2 997 swap sent you his way.

pete95zhn

Hi Rob!

No, you're not the first one. It can be done and it's not even that difficult. But there will be some issues.
Mechanically it's easy, engine will almost bolt on:
-Just modify carrier plate on the engine for NA' motor mounts and move transmission carrier mounting bolts to other threads on the body.
-Buy turbo's transmission and install with turbo's drive shafts
-Modify rear cooling lines.
-Install turbo's (or AM) fuel pump and return line.
-Sort out effcient water to air intercooling system and install. Steath and good for street. Search for bbi's solution for turbo'd Pike's Peak 997 GT3.

Then there's electronics. You already have Motronic with VarioCam Plus controls, so based on my own adventures in the wonderland I'd recommend using it. Discuss with a good tuner for reprogramming and use external boost controller. '03 Carrera and turbo should (in 99% probability) have similar engine sensoring (except inlet air pressure) thus also similar wiring loom, so there shouldn't be problems that couldn't be solved.
Switching to turbo's Motronic would cause issues:
-While your car is 2wd and turbo is 4wd, your ABS/PSM pump will not discuss with that Motronic and would have to be changed. (Although I did not get definitive answers years back if the Motronic could be reprogrammed or not in this aspect... ABS/PSM unit can't, they're model specific).
-Instrument panel would have to be changed too.
-Fortunately your car already has CANbus, in mkI's HVAC and lot of wiring would also have to be changed with turbo's Motronic. Don't ask why I know this...
- Switching to GT2's Motronic would lead to new instrument panel, ABS (and losing PSM) and new fuel level metering.
- One basic difference there is between NA and turbo engine (and instrument panel): engine oil level measurement. The logic is different and lost with the swap. Install GT3/Cup oil dip stick and live with nuisance warning.

Before starting the swap compare turbo's and Carrera's PETs for part number differences WSM for wiring loom differences to find out what's different in engine electronics.
-IAT measurement for sure.
-coil pack wiring possibly (in mkI's certainly)

Keep Carrera's stealth looks and enjoy the surprise.

PS: I'd upgrade suspension and brakes to match the increased performance. Then there's these normal power and performance upgrades widely discussed.

robflying

Eureka I knew that this had to have been done, it just makes sense. Now Pete if I may, how would my Motronic? Unless there is a way to tap in the secondary air sensors and thats plural sinse there are 2 turbos, which monitors the turbos boosted air I don't see it. Please Obie one I'm listening!

RngTrtl

with enough time and money anything is possible.

pete95zhn

.6 turbo uses one MAF, air to turbos is split after it. .7 turbo has two MAFs, one for each turbo. Yet on both cars MAFs (Bosch) are located just after air cleaner housing. Now I use .7 turbo air cleaner housing with one MAF (Hitachi). How it's possible? Well, the input signal is doubled in Motronic tune. Seems to work...

I haven't looked into 996.2's Motronic's inputs. There may be a possibility to add a intake pressure (MAP) sensor, then it would be quite straightforward. @ WOT with MAP, otherwise with MAF. But, I recommend you to contact some Motronic wizard with these questions. Previously suggested Dundon is one alternative. I got my questions solved locally.

I had a long and comprehensive build thread at Renntrack, but it got hit by an asteroid and burst into flames so everything was lost. Still something can be found from here.

strathconaman

Instead of an air-water IC, Have you thought about a top mount IC like the 993 TT? It may involve making a custom ductail or whaletail...but what would be so wrong with that?