There are downsides and benefits to the conversion.

Sure the aftermarket systems dont have the fancy knock retard that the stock EZK has.
But you can loose the distributor caps/rotors, go to COP or CNP, ditch the MAF, the old style TPS. And many other advantages.
That said it is NOT for everyone. There is also the benefit that you can plug any laptop into it download the software with ease, and be able to identify the problem that you might be having almost right away.

Dont get me wrong the stock system is a great system, but for some people a standalone system is the way to go!

 

If you can't sort your stock system I doubt you will be able to install a full custom system.

 

bingo and hence the comment to have someone else performe the install.

 

The features make MS2Extra desirable. I have always wanted to do an ITB setup on a car eventually, so I thought it would be great opportunity for this upgrade until that time comes. I have never had so much trouble with a Porsche until now. It is ridiculously frustrating to diagnose while not being able to drive it. I feel that with today's advances in EFI it would be more practical to modernize something obsolete.

Also, how difficult would it be to fit to an automatic car? I think the EZK reads some switches on the transmission to retard timing between shifts.

 

Andy, Have you tried swapping engines to see if that fixes your prolems?

 

Any shop in Calif that tampers with a factory system is risking its license and pretty nasty fines.

Is this more of a pie in the sky thing, or are you seriously thinking of doing a conversion?

 

Both.

 

Carl's harnesses are $729.00 for your car. I'd go through your fuse/relay panel and replace the engine harness. You'll come out $$ ahead and probably fix a few other issues you don't know about yet. JMHO.

 

Carl's harness listed on his site does not appear to be the injection harness though. He specifies Engine Wiring harness, but the Injection Harness is completely separate. His is the side with the 14-Pin connector. Unless, he has made an LH harness and has not posted it on his site yet.


Andrew - Of course I have not tried a new engine. However I am still living a life fearful of thrust bearing failure in this car. Last release I had no movement despite prying back on the flywheel firmly.

 

Andy:

With all seriousness, I think you need to ask yourself what you expect from your car ??? I say this as working with engine management systems can surely be a LOT of fun, but it rarely leads to simplified troubleshooting over a stock car, living with it on a day to day basis.

In doing one of these systems on a car that you expect to drive day to day and get open assistance in torubleshooting, I think you'll find the pool of specific knowledge incredibly shrunk from what you have now from the 928 forum with a basically stock car running LH and EZK.

To give you some perspective, I have setup Electomotive, MoTec and Haltech systems on a couple of difference cars, including a forced induction 16V 928. The work is always incredibly fun but I would never think of stripping out an OEM mature system like the LH/EZK combo unless I had a specific tuning need in mind. Unless I am missing something with you and your 928, simply not being able to fix the OEM setup is not a great launching point to venture into the aftermarket engine management fray.

In setting up the aftermarket gear, you'll have to setup different sensors, in the manner the new system mandates, possibly troubleshooting these new signals based on your specific engine parameters, possibly make a few custom brackets, etc., and all to a standard of the OEM equipment if you want to rely on the aftermarket system everyday. Please take the above as a referenced "heads up".

From where I suspect you're situated, it's easy to see that you might have a ton of initial fun shopping, playing with software on your PC, etc. as you start into a project using one of the aftermarket solutions. But with an actual purchase will come many experiences similar to where you have used the "head bang" smiley in your request for assistance posts. If you are OK with more of the same type "head bangs" and you are confident that you can power through these items, likely on your own. With this in mind and in check, you'll likely have some fun times and reap the rewards of these very cool systems.

$0.02

 

I hate you guys. I think I want a Sharktuner now...

Whatever it takes to get some sort of diagnostic system to figure out what the heck is going on under the hood or in the wires that is causing my idle issues... I am looking into a replacement LH harness too.

 

Hi Jim,

For Megasquirt, at least, I can say that this is not true. Megasquirt will work with just about anything that major DME manufacturers used stock. You can calibrate for any NTC temperature sensor, you can use stepper or PWM idle control valves, you can indicate a variety of TPS setups and calibrate potentiometer ones, you can use pretty much any MAP sensor and most MAFs (although you might need a calibratiion curve on the MAF), and you can use pretty much any combination of hall, optical, or VR cam and crank position sensors... about the only thing it won't handle (that I know of) is non-contiguous, non-symmetrical missing teeth on a wheel.

The more challenging work for a newbie would be figuring out what sensor is where, modifying the harness, and determining things like the best dwell settings for stock coils. A 928 might further complicate things, since it's one of the few cars to have separate ECU's for fuel and spark, and has a few "extra" sensors to account for this. On the other hand, as I mentioned before, this also opens the possibilty of keeping EZK but using MS for fuel, or swapping fuel first and spark later.

On my motorcycle FI project, I had to do fuel and spark at once, since the Microsquirt box went in where my original ignition control was (needed the space). That definitely made things more complicated. It's also MUCH harder to adapt FI to a carbureted (and air cooled!) engine, than it is to swap an existing DME for different stand-alone system.

Andy, if you like tinkering, can stand some frustration, and feel up to REALLY learning how the whole engine management system works, then a system like MS would probably be a good idea. If you just want to drive the car, then it wouldn't be such a good choice.

My .02 anyway.

Cheers,
Paul

 

Well considering the fact I'm not building a track car, but a restomod, I guess I'll stick with the LH and just RNR the wiring and grounds. I may not need a new harness afterall, but perhaps some cleaning and cutting back some of the corrosion, and redoing the connectors after. I also saw the price for an LH harness new and my heart paused.