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-   -   My 2.7l EFI project with Carrera intake (http://forums.pelicanparts.com/porsche-911-technical-forum/821431-my-2-7l-efi-project-carrera-intake.html)

Tippy 01-12-2015 05:39 PM

Quote:

<div class="pre-quote">
Quote de <strong>cmonref</strong>
</div>

<div class="post-quote">
<div style="font-style:italic">An MS will drive a "smart" coil directly -- the ones that have the driver setup onboard -- but requires a driver for the others.</div>
</div>I take this to mean that it has no large driver transistor to ground the coil but can MS control dwell times? I guess I'm asking if MS can send a signal to indicate when to start charging the coil and then when to fire it?<br>
<br>
I'm just wanting to compare to what the stock motronic does. The stock motronic has a large darlington transistor that 'grounds' the coil's '-' terminal to start charging the coil for a given dwell time then once the dwell time elapses the transistor shuts off and the coil fires. <br>
<br>
So does MS control dwell and firing event or does it only indicate when to fire with no dwell control?
Someone may correct me if I'm wrong, but yes, it will fire coils. Read a lot a few years ago with people experimenting with nearly every COP or CNP out there and the headaches they encountered guessing dwell and such, and decided just to go Ford EDIS wasted spark due to simplicity.

cmonref 01-12-2015 05:40 PM

Each coil has a high voltage plug wire and a 4-wire control set (12v to charge, 5v for dwell control, gnds for each.) They are best seen on coil #1, near top, plug wire to the left and control wires on the top right end.

Coils 1-3 have plug wires pointing left, with 4-6 pointing right. Three plug wires from 4-6 can bee seen headed to the right. Control wires for 4-6 are visible beyond the 1-3 plug wires. Coils on top row are 1-4-5, and on bottom 2-3-6.

The ignition is true sequential. Uses 60-2 with hall sensor on the crank and a hall sensor in the distributor for phasing. Sequential gives lower amperage peaks on the 6 12v charging wires than wasted spark would give.

djb25 01-12-2015 06:58 PM

Quote:

Originally Posted by cmonref (Post 8436908)
Good choice! I have them mounted on an aluminum plate that sits on the three 6mm pads on the left intake. 6mm threaded rod and aluminum spacers are used to bolt the two-high stack of coils to the plate, and the plate is then bolted to the intake. This allows the coils to be removed easily as a group, if for instance, you want to replace a coil -- you can do it on the bench. The coils are connected directly to the MS, and 3.2 plug wires are used.

Nice setup!

I may have to bend your ear a bit once I get to the ignition stage.

will hung 01-13-2015 05:33 AM

Quote:

Originally Posted by djb25 (Post 8436593)
I actually coated the intake with "Cerakote" - it's a ceramic based finish normally used on firearms. I used the "stainless" color. I'm pretty happy with how it turned out.

It actually looks way better than in the photo. There's actually a better picture earlier in the thread.

Awesome. Thank you. I've seen wrist watches that were coated with Cerakote.

djb25 01-13-2015 10:52 AM

Quote:

Originally Posted by jpnovak (Post 8436260)
If you really want to save money then drill your stock pully and mount some magnets in it. Build a Hall Effect sensor pickup and send this signal to the ECU. The advantage of the Hall effect is that it is a 12V signal and the Signal/Noise ratio is significantly improved at the expense of timing control. Your timing control will only be as accurate as the position of the magnets. This will still be more accurate than a distributor pickup and allow for timing control.

This is an interesting idea. I have a mill and a rotary table, so I could make a magnet-embedded wheel relatively easily. I could get a piece of aluminium and drill 36 holes around the circumference, and epoxy a small magnet in each hole. Bolt the thing to the existing crank pulley. Done.

If I left one magnet out, would I have a missing tooth wheel?

However - I notice that this doesn't seem to be very common. Embedded magnet wheels seem to be very rare.

I guess the toothed wheel would be faster and cheaper to construct, but is there more to it? Does a toothed wheel have greater precision?

Obviously I'm completely new to all of this...

djb25 01-13-2015 11:10 AM

For example, I can get 50 of these tiny neodymium magnets from Amazon for $7.89:

http://forums.pelicanparts.com/uploa...1421179020.jpg

They're 1/8" cylinders that are 1/8" long, but they're neodymium, so they should still be very, very strong.

I'm really just looking for an effective and reliable way to do this - I certainly could just buy the Clewett setup or make my own version thereof.

dede911 01-13-2015 11:19 AM

Sal,

what type or brand of MAF do you have?

It's a very nice installation.

André

scarceller 01-13-2015 12:18 PM

Andre,

The actual MAF is from PMAS (google them) but the solution is my own. I re-wrote the entire air fuel model in the motronic software to fully support a MAF. My solution does not make a MAF pretend it's a AFM. Trying to make a MAF mimic an AFM is a marginal solution, I spent 6+ years developing this solution.

Quote:

Originally Posted by dede911 (Post 8437968)
Sal,

what type or brand of MAF do you have?

It's a very nice installation.

André


TimT 01-13-2015 12:52 PM

Quote:

If I left one magnet out, would I have a missing tooth wheel?

However - I notice that this doesn't seem to be very common. Embedded magnet wheels seem to be very rare.

We have used magnets as triggers wheels on a number of builds we have done with Haltech ECUs. Typically we use four magnets on the crank pulley, three are spaced 120 degrees apart and have the north poles facing the sensor, one magnet is placed a few degrees before the magnet located at TDC, this magnet has the south pole facing the sensor. This tells the ECU to start the events....

Also Sometimes we use the distributor, or a cam angle sensor if the system is sequential...

Tippy 01-13-2015 02:58 PM

Wow. How do you have any accuracy control with ignition? Or are you doing fuel control only?

TimT 01-13-2015 03:30 PM

Fuel+ Ign

It motivates this car quite well...... 840 hp

and quite reliable

http://forums.pelicanparts.com/uploa...1413842162.jpg

Tippy 01-13-2015 03:37 PM

Hmm, amazing.

TimT 01-13-2015 03:50 PM

This is the one of the cars we built using Haltech... and a four magnet trigger...

Not bad


<iframe width="420" height="315" src="//www.youtube.com/embed/uZnjfaNMJZA" frameborder="0" allowfullscreen></iframe>

cmonref 01-14-2015 11:07 AM

Quote:

This is an interesting idea. I have a mill and a rotary table, so I could make a magnet-embedded wheel relatively easily. I could get a piece of aluminium and drill 36 holes around the circumference, and epoxy a small magnet in each hole. Bolt the thing to the existing crank pulley. Done.
I did this with a 4mm aluminum disc. Glued 1/8" neodynium magnets (from K&J Magnetics) in with epoxy. Bolted disc to back of crank pulley. Made a mount for Hamlin 55100 hall sensor. Worked well but apparently ran into over temp condition for the hall which resulted in unreliable running. Abandoned this in favor of a Clewett pulley and 36-1 toothed wheel, Clewett mount for sensor, Allegro hall potted into a 3/8" aluminum spacer. If you go this route, get a hall sensor good to 150C instead of the 85C that I had.

http://forums.pelicanparts.com/uploa...1421265433.jpg

http://forums.pelicanparts.com/uploa...1421265536.jpg

http://forums.pelicanparts.com/uploa...1421265848.jpg

http://forums.pelicanparts.com/uploa...1421265958.jpg

Quote:

If I left one magnet out, would I have a missing tooth wheel?
Yes. Drill 36 holes at 10 degree spacing, leave one magnet out gives 36-1.

Tippy 01-14-2015 11:35 AM

I still don't see how the ignition has accuracy, but it works and that's all that matters.

djb25 01-15-2015 10:43 AM

Quote:

Originally Posted by cmonref (Post 8439559)
I did this with a 4mm aluminum disc. Glued 1/8" neodynium magnets (from K&J Magnetics) in with epoxy. Bolted disc to back of crank pulley. Made a mount for Hamlin 55100 hall sensor. Worked well but apparently ran into over temp condition for the hall which resulted in unreliable running. Abandoned this in favor of a Clewett pulley and 36-1 toothed wheel, Clewett mount for sensor, Allegro hall potted into a 3/8" aluminum spacer. If you go this route, get a hall sensor good to 150C instead of the 85C that I had.

This is why I love this forum. No matter what you are thinking of, someone has tried it!

Sounds to me like I'm better off just getting a 36-1 toothed wheel and a good high-temp hall sensor. Any idea what Allegro sensor you used?

djb25 01-15-2015 11:07 AM

Okay, progress is being made on the fueling front.

As I mentioned earlier, my LC-1 died on me. It kept throwing error after error and just simply would not work, even with a brand new Bosch sensor.

So I did a bit of research and decided to replace it with an LC-2.

The LC2 is significantly smaller that the LC1 and is a much simpler installation. No more external LED and calibration button, so only four wires - power, ground, and two analog outputs.

The manufacturer recommends that the LC2 be installed in the passenger compartment, not in the engine compartment. It comes with a very long sensor adapter cable to make this possible.

This actually turned out to be really annoying, because my wiring harness was all set up for the LC1 in the engine compartment. This meant tearing down the wiring harness in the cabin and snipping the 02 input wire so I could run it to the LC2. I also had to run a new switched power line into the cabin and run a ground line back to the engine.

Frankly, I'm not sure that it was necessary to run the ground from the engine all the way into the cabin, but I wanted to keep the grounding consistent for everything.

This may not have sounded like a big change, but it took the better part of a day to remove the LC1 wiring and to rewire the car for the LC2. I actually ended up adding a relay in the trunk for the LC2 because I didn't want to piggyback on some other accessory power source.

I started her up and the LC2 was showing a pretty solid 19:1 a/f ratio, which seems awfully lean. I didn't have much time to investigate last night, but tonight I'll find out if it is reading correctly, etc.

scarceller 01-15-2015 11:16 AM

Quote:

Originally Posted by djb25 (Post 8441119)
and snipping the 02 input wire so I could run it to the LC2.

What does this mean? You didn't cut the WBO2 sensor wire, did you? You can't cut the length of the wire on a WBO2 sensor as it will effectively decalibrate it.

19AFR is way lean at idle. These motors like to idle at 14.0-14.4 no leaner.

cmonref 01-15-2015 12:01 PM

Quote:

Sounds to me like I'm better off just getting a 36-1 toothed wheel and a good high-temp hall sensor. Any idea what Allegro sensor you used?
Oops -- the Clewett wheel is 60-2, not 36-1 as I stated. (I had another 36-1 wheel that I did NOT use when I went to the Clewett.) It came that way, so I used it. I am quite certain that 36-1 would work just as well for this purpose.

I used an Allegro ATS627LSGTN-T (DigiKey 620-1398-1-ND.) The picture posted earlier was showed it sitting in the 3/8" spacer bored to 8mm, before potting. As pictured, the sensor's leads had been bent 90 degrees, it was wrapped in special tape, and then in shrink wrap in preparation for being potted in epoxy. The sensor has two hall sensors and must be oriented properly (if backwards, it will read negative RPM as I recall.)

Regarding grounding: common ground of all sensors at the MS is very important. If you ground elsewhere, you will introduce ground path errors that will throw off the sensor readings. Don't want to do that with the oxygen sensor.

By the way, my engine is on the stand right now (body is at the painter's). I'm replacing the single LC-1 with dual 14.7Spartan controllers and sensors.

Heed Sal's advice on cutting of the O2 harness. Double check your manufacturer info.

scarceller 01-15-2015 12:12 PM

As already pointed out, grounding of ALL things EFI is very important and the stock 3.2L Motronic's main ground point for all Sensors and the DME is on the ground screw located on intake runner for cyl #1. You can see all the brown wires grounded at that point if you look at my engine bay pic earlier in the thread. I suggest using that same factory ground location for any aftermarket EFI, I suspect Bosch and Porsche did the homework on that location.


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