MSD 6AL-2 Digital Programable Install and Distributor Lockout
 

I installed the MSD a while ago and finally got around to locking out the mechanical bottom half of my distributor to experiment.

Note: I previously locked out the vacuum plate see thread at:

http://forums.pelicanparts.com/porsche-911-technical-forum/662781-diy-distributor-vacuum-pod-delete-vacuum-lockout.html

Picture below shows the installed MSD with serial cable attached, I used an USB adaptor and hooked it up to a laptop running Windows 8.1. It would be really nice if this thing was wifi or Bluetooth.

http://forums.pelicanparts.com/uploa...1391489635.jpg

This shows the distributor fully advanced, I decided to lock it fully advanced but I don't know for sure if it is necessary, but it seems that it is recommended. I did lock the stator at mid point, I'll check rotor phasing later. I don't think it's an issue.

http://forums.pelicanparts.com/uploa...1391489684.jpg

I created a locking plate from a thick piece of aluminum. I traced a card board template first.

http://forums.pelicanparts.com/uploa...1391489708.jpg

The plate looks a bit rough, but it does the job. It is wedged in there pretty good, no wiggle room.

http://forums.pelicanparts.com/uploa...1391489818.jpg

I put the assembled distributor back in the exact setting I had removed it with the adjustment nut centered in the hole, the rotor was pointing about 12 degrees advanced past the timing mark on the edge of the distributor.

Set my RPM limit.

http://forums.pelicanparts.com/uploa...1391489740.jpg

Programmed a basic curve.

http://forums.pelicanparts.com/uploa...1391489760.jpg

Car started right up, I adjusted the timing so that it is 6 degrees advance at the crank at 1000 RPM.

The MSD pulls out 24 degrees at 0 - 800 rpms.

As the rpms increase it reduces the degrees it pulls out so at 3000 rpms it is pulling 0 degrees out, and at the crank the timing is advanced to 30 degrees (24+6).


http://forums.pelicanparts.com/uploa...1391490884.jpg


Ok I am happy, the software was easy to use and I could manipulate the curve with the engine running. It's really nice to be able to see how the engine responds to different changes to the curve.

Now, who can tell me what type of a curve I should program? Is the stock curve optimal? Should I add timing at idle to smooth it out?

Here is a link to the software instructions if you want to read about it;
http://www.msdignition.com/instructions/graphviewdemo.pdf

This is cool! Looking forward to hearing about what advance profiles people suggest.
Ron

Thanks Ron, I'm studying this thread for information;

http://forums.pelicanparts.com/porsche-911-technical-forum/582675-best-advance-curve.html

It seems that I should be able to use an initial setting of 10 degrees advanced through about 800 rpms, This will allow easier starting and a smoother idle. I think it will burn cleaner as well.

Then I will drop the advance to 8 degrees through 12900 Steady advance to 20 total at 2500 and then a little steeper to 32 degrees at 3500.

I think that is about as good as it's gonna get.

Careful!
There appears to be a green reptile invading your engine compartment.... :)

Cool stuff, very interesting.

Hey Shane, I forgot to ask you if you needed a tach adapter with this box? I'm about to sell of my Street-fire and my current dizzy to fund this and wanted to knock it all out at once. Fortunately, I have a 2nd diz that I had dissembled and borrowed a few things from for the one in the car but all of that was stuff no longer needed if I'm going to lock it out. Every now and then the stars align I suppose.

Yours looks like the 6530 in the pic so can you just confirm that for me so I don't buy the wrong one? I didn't see anything on Summit that made me think otherwise but just wanted to be sure. Thanks Buddy!

No tach adaptor needed, yes it is the 6530.

Pay close attention to the tiny pin that holds the starfish thingy on the distributor, it is very easy to loose. I am researching the method to check for phasing issues now. It looks like I just drill!a hole in the distributor cap, paint a center line on the rotor tip, and use the timing light to check the where it is sending spark, if it rotates out of a certain arc then I may have to readjust the lockout of the vacuum plate.

Yep, I can't figure out if he's British or Aussie, I wish the little bastard would speak English.

Is the rotor alignment OK? I think you sort of locked things down in a middle advance position.

Have you thought of going to a crank fired sensor? Seems to me that would be the way to go so you don't have to worry rotor alignment problems.

I have just installed a Daytona-Sensors CD1 in my 1973 and love it, but I using the mechanical advance because rotor phasing really bothers me.

the CD1 can be programmed even for retard under boost with the MAP sensor hooked up.

Doe the MSD log data? Can you study the RPM, Advance, MAP with charts? Just cuirous.

Checking Rotor Phasing
 

The rotor fires at the trail edge of the stud at idle. As the RPMs increase the rotor fire moves from the trailing edge, to a little right of center at full advance.

I think it is by dumb luck that it works like this, as WOT is the best place to fire the rotor center mass.

I am going to attempt a video, for now I can share a few pics of the test equipment;


http://forums.pelicanparts.com/uploa...1391910000.jpg

Rotor Phasing Video
 

Sorry for the production quality. The angle of the camera exaggerates the alignment. And the hole is a little off center to the right.

The distributor rotates CCW.

<iframe width="560" height="315" src="//www.youtube.com/embed/k4tz4IWCJiw" frameborder="0" allowfullscreen></iframe>

Revised Curve
 

Here is the timing curve I ended up with. Idle is smoother. No notable change in transition. I don't think Ill be able to get any closer until I get this on a dyno.

http://forums.pelicanparts.com/uploa...1391913332.jpg

The rotor alignment seems OK. I have not really considered a crank fired sensor, this seems to do what I need it to.

I do not believe the MSD logs data.

Hey Shane, I'm curious what you are seeing with this setup in terms rpm settling? Not sure I'm wording this right but what I mean is now that the magnets in the diz no longer have to flop back when off the throttle does it appear you are getting a more accurate or more responsive tach response? I was playing with the STE on the PMOs yesterday waiting in between adjustments for things to smooth out and got to thinking about this.

This could be yet another reason to go digi. Not sure how big of a deal it really is but not having to wait for the magnets to do their thing returning to position is certainly a nice thing in some situations.

I haven't noticed anything different with tach response. My tach always seemed to be dead on right, before and now. Your tach response delay is odd, perhaps try another tach.

I had to flip my laptop over!!!

Ha! What's your thoughts on the rotor phasing?

The graph is the measure of degrees that the MSD pulls out.

The bottom of the graph starts where I set the static timing, at 6 degrees advanced at the crank. So the 24 spot of the graph equals 8 degrees advanced at the crank.

The top of the graph which reads 0 is 32 degrees advanced at the crank.

The MSD allows for 25 degrees.

I could set the static timing at 10 degrees and get a total of 35 degrees advanced.

Why are my pictures loading upside down?
 

Bumped static timing to 8 Degrees BTDC. Total 34 degrees. 9.5:1 compression Ratio.

http://forums.pelicanparts.com/uploa...1392509392.jpg

Pretty good article on getting timing right;

AutoSpeed - Getting the Ignition Timing Right

Concerning rotor phasing, I feel it is really critical. I have advance and retard programming in my CDI, I am using a Daytona- Sensors CD-1.

I would not use the timing programming in the CD-1 unless I had a crankfire setup for determining where the the crank is positioned.

Where you able to see the video above that shows the rotor phasing with my system? I think that it shows that rotor phasing is not an issue.

The Daytona system is an excellent set up, but a lot higher priced than the MSD.

I can also confirm that rotor phasing is not an issue when using an SC distributor in a road car.

If, however, you have a high revving early race car, the reduced cap diameter can mean that the phasing could start become an issue once you get above 8000 RPM in a true multispark system (like our CDI+). The phasing can be dialled in on the cap by filing the location tab, allowing the cap to be turned and set. On our system, the time before the second spark can also be reduced. This is all best done on a dyno.

Because the MSD doesn't deliver multiple sparks above 3000 rpm, it doesn't have so much of an issue.

I have the Electromotive XDi twin plug system on my 3.3SS engine. Compression is about 10.8:1, large port CSI system, Carrera large port heads and 964 cams. The Electromotive manual suggested a starting advance curve of 10 degrees initial, 22 degrees added at 3000 rpm and -2 on the top end. After lots of "twiddling", I now have the advance set at 5 degrees initial, 20 at 3K with 0 retard (total advance of 25 degrees). The engine idles well and pulls like a scalded cat all the way up to the 7500 rpm ignition cutout. I found that anything more than 5 degrees initial advance made it difficult to get the engine to idle at 950 rpms. This is the best setting that I have found to date, but will keep on experimenting!

I'm exposing my ignorance here...but..

I was trying to figure out how the MSD box got the rotor position data to determine the degrees to advance? Meaning, does it just time the triggers from the dizzy and interpolate degrees from that, or is there an actual measuring source that you install (like a trigger wheel)?

I guess that spider would give 60 degree triggers, and it might be able to interpolate from there, but it seems like calculating 1 or 2 degree rotation with a rapidly accelerating timing source would be hard. Maybe it's not?

Yes, it's as simple as that, i.e. just determine the time between trigger inputs and convert that
to a RPM, and then have a lookup table for the advance. The next spark is determined from the
next trigger input and the process is repeated.

The algorithm used can compensate for rapid RPM changes.

One such algorithm (MS) is described here:

Alpha-Beta-Gamma Filtering

As long as you have enough data (e.g. multitooth crank wheel sensor) you can make that one work. With only three trigger points per rotation, the prediction algorithm becomes a little trickier.

There're other algorithms that can be used that solve the basic issue without a ring gear type
of input signal.

Hello,SmileWavy
i come back with this post because i would like to lock the distributor like snbush67.
I have an distributor for a porsche 2.7 with points and i would like to install a hall effect sensor.
If your read my message, is it always ok with your plate in alumunium:)? No problems any more?
Thank you for your answer.
Regards

No problems with the lock-out plate that I installed or the position that I locked the distributor advance at.