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944 Wasted Spark
https://forums.tipec.net/viewtopic.php?f=25&t=12549		 Page 1 of 1
Author:  barks944 [ Fri Mar 16, 2012 6:17 pm ]
Post subject:  944 Wasted Spark
I have just installed a VW Audi wasted spark coil pack system to my 944 Lux to replace the coil and distributor. Will in future fit a more advanced type of ignition system like coil near or coil on plug but this was a simple place to start. This uses a modified version of the standard DME which among other things has extra outputs for wasted spark. Just a quick video to show the installation and the engine up and running. I've just driven it home and it feels very good, nice and smooth :).

http://www.youtube.com/watch?v=P4_y33HC6cE&feature=youtube_gdata

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Author:  Althejazzman [ Fri Mar 16, 2012 8:41 pm ]
Post subject:  Re: 944 Wasted Spark
I thought the 8v Lux couldn't really be tuned much. What's the advantage of this ignition system?
Author:  barks944 [ Fri Mar 16, 2012 9:23 pm ]
Post subject:  Re: 944 Wasted Spark
This project is much more than a new ignition system, it is a plug and play fully live re-mappable MAP based injection system for the 944. Check out the DME project link in my sig.

One of the reasons you can't tune the Lux much is that its injection system is pretty basic. This system basically gives you a modern standalone but is plug and play. Now that I can remove the AFM there is much less intake restriction and the system is live remappable. This means you can now fit new camshafts etc etc and setup the ECU properly to suit. Throttle response is also greatly improved, the engine feels much more alive and is very punchy. Should have dyno results soon. By providing wasted spark outputs you can fit pretty much any modern ignition system (which gives much better spark than a dizzy/coil) to the 944 which was not possible before. I just chose a basic coil pack for this setup I am not sure how much better this is than the dizzy/coil yet.

It also opens up the route to supercharging the lux engine as well, it is a very strong engine (944 Lux in the US was turbo charged to 400hp on E85).
Author:  kongsodoken [ Fri Mar 16, 2012 9:33 pm ]
Post subject:  Re: 944 Wasted Spark
guess what I want.... :lol:
Author:  bertelli_1 [ Sat Mar 17, 2012 10:04 am ]
Post subject:  Re: 944 Wasted Spark
I dont think you can underestimate how much better a coilpack is compared to a distributor / coil, no maintenance & a much better spark. Good work barks!
Author:  robmal [ Sat Mar 17, 2012 11:21 am ]
Post subject:  Re: 944 Wasted Spark
I want this kit for my 944 S2 too, hope you are working on it! 8)

Cheers

Rob
Author:  Richclarkes2 [ Sat Mar 17, 2012 4:53 pm ]
Post subject:  Re: 944 Wasted Spark
I'd love to get rid of that ugly AFM on my S2! Makes the place look untidy.
Plus it cant be doing much for airflow.
Rich
Author:  barks944 [ Sat Mar 17, 2012 5:49 pm ]
Post subject:  Re: 944 Wasted Spark
Well having driven it about for a day I'm am very pleased. The engine seems a lot smoother all over, also very quiet during cruising. The ignition map is totally un-tuned too. Once you ditch the AFM you really notice the pickup of the engine is much better. Its neck snapping now when you stamp on it as fast as you can in 1st gear. The car doesn't jar or anything it just launches :D.

I also switched to a fixed fuel rail pressure, which has given a nice improvement as one of the results of removing the AFM is that the MAP increases much more rapidly as the AFM was almost like a pressure change damper (almost a throttle really). You can see the vacuum it creates by blipping the throttle in the engine bay and watch the intake boot shrink due to the vacuum. The negative impact of the fast changing MAP is that the fuel rail pressure regulator can't keep up with the MAP changes. It's trying to maintain a 2.5 bar differential with manifold pressure (rising rate). This means you can burn lean if you stamp on it as the fuel rail pressure is momentarily low and you get less fuel than you think. Now that the fuel pressure is fixed I no longer have that to worry about and the throttle response on my 944 is awesome and its not even been mapped properly :D.
Author:  DaveM [ Sat Mar 17, 2012 8:24 pm ]
Post subject:  Re: 944 Wasted Spark
Excellent work. Have been making plans to get rid of the rotor arm and cap so am very interested in this part of your project
Author:  jameso [ Sun Mar 18, 2012 1:34 pm ]
Post subject:  Re: 944 Wasted Spark
barks944 wrote:

I also switched to a fixed fuel rail pressure, which has given a nice improvement as one of the results of removing the AFM is that the MAP increases much more rapidly as the AFM was almost like a pressure change damper (almost a throttle really). You can see the vacuum it creates by blipping the throttle in the engine bay and watch the intake boot shrink due to the vacuum. The negative impact of the fast changing MAP is that the fuel rail pressure regulator can't keep up with the MAP changes. It's trying to maintain a 2.5 bar differential with manifold pressure (rising rate). This means you can burn lean if you stamp on it as the fuel rail pressure is momentarily low and you get less fuel than you think. Now that the fuel pressure is fixed I no longer have that to worry about and the throttle response on my 944 is awesome and its not even been mapped properly :D.


It's interesting that you mention that. With mega/microsquirt there is an acceleration enrichment setting and I never managed to get it consistantly right on the lux engine. Didn't think to look at the FPR.
Author:  andycowman [ Tue Mar 20, 2012 9:38 am ]
Post subject:  Re: 944 Wasted Spark
I would very much like to understand more about this, I have Dizzy/rotar on the Turbo but running the Emerald I know I can switch to coil packs. They suggest some from a ford that work nicely with the ECU.

What I would like to know more about though is what you do about removing the old ECU and positioning the coil pack?!

Great work by the way!
Author:  barks944 [ Tue Mar 20, 2012 9:44 am ]
Post subject:  Re: 944 Wasted Spark
I didn't remove the old ECU. The ECU is just a modified version of the standard motronic unit so its plug and play and the wiring loom is the standard 944. This is a MAP based setup with additional outputs for wasted spark.

I had a spare cam box end cover so I simply drilled holes in it and bolted the coil pack on. You need to check for a good ground to the cylinder head and that it clears the end of the camshaft. I am probably going to get something machined that will bolt to the cam housing end cover without modification and provide mounting for the coil pack.

Tom
Author:  andycowman [ Tue Mar 20, 2012 1:47 pm ]
Post subject:  Re: 944 Wasted Spark
whoops - I didnt mean ecu I meant to say about removing the old dizzy!

Luckily you answered that anyway :)
Author:  barks944 [ Tue Mar 20, 2012 2:49 pm ]
Post subject:  Re: 944 Wasted Spark
The other thing to consider is how you are going to trigger the RPM gauge. You will need to disconnect the old coil and depending on how you have setup your wiring your RPM gauge might not work any more. I know how to fix this on my setup but I am not sure how to do it with yours, or if it will even be a problem!
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