<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ButterBall &raquo;</TD></TR><TR><TD CLASS="quote">

The maximum/minimum AC voltage that any VR sesor produces is constant. Look at this picture of a sine wave:


The peaks and valleys will always remain at the same signal intensity/strength. However, the time (T) to complete one sine oscillation will decrease as engine speed increases. In the previously posted picture, the sine wave closest to the top would represent a low engine speed VR sensor output. The sine wave closest to the bottom would represent a high engine speed VR sensor output.

The problem with the AEM EMS has nothing to do with voltage strength. It's all about the long oscillation period at low engine speeds. The ecu needs sharp changes/oscillations from the vr sensor to properly decode engine position.</TD></TR></TABLE>

I don't think that is correct. With a VR sensor, both the amplitude and frequency change with RPM. Some ecu's, such as motec, let you set the a voltage curve by rpm to help eliminate noise related problems. For instance, you might get 500mv at 500rpm and 3 volts by 5k. You can tell it that at 5k, don't pay attention to anything under 2.8v. There is also a window in crank degrees that it tells the computer to look for the signal. This way small voltage signals created by RF noise will be filtered out. I think this is the type of stuff the AEM lacks and the reason it has problems with VR sensors sometimes.

 

Here's a spec sheet for a VR sensor (output in mv/Hz y-axis vs. airgap in inches x-axis):

http://www.delphi.com/pdf/ppd/sensors/ch_vr.pdf

Scroll down in that link and you'll see it. It's a pdf, so I can't link the picture directly.

Notice that the output is fixed at mv/hz, depending on air gap. For each oscillation of the sine wave, the maximum output does not change - it remains constant. The overall voltage change you read with the motec is a result of more instances of magnet passing ferrous metal as engine speed increases - not VR oscillation voltage changing.

Suppose that the sine wave jpeg I posted is a series of VR sensor outputs at different frequencies/engine speeds:
Where the peak voltage/oscillation = 25mv
The uppermost sine wave --&gt; two oscillations per run --&gt; total ouput to ecu = 2*25mv ---&gt;50mv

The lowest sine wave --&gt; sixteen oscillations per run --&gt; total ouput to ecu = 16*25mv ---&gt;400mv

But yeah, that probably is a better way of explaining why the AEM EMS has problems with the honda distributor, that the motec/honda ecu's don't. I've never used a motec before. Sounds slick.

It's all theory though. I'm thinking that the MSD distributor might use bigger magnets/sensors that better satisfy the AEM (nicer signals in the lower rpm range)? I'd have to actually test it myself to be satisfied, though.

 

Tony is right about the amplitude changing with the frequency



Here's the site it's at the bottom of the page

http://www.kettering.edu/~drus....html

 

It's nice and all to have this debate, but I haven't seen any type of VR sensors that would create zero voltage when the power supply (+12v) is off with the magnet passing over the sensor...

The MSD unit would only create voltage at the trigger wires until I cycled the switched 12v to on. Only 3-wire Hall Effect sensors would do this unless I am missing something here...

Plus MSD already has a Hall Effect cam sync sensor with LED that you can buy right now. So I am quite sure MSD already manufactures or offers Hall effect -equipped products and would not lie to their customers. Claiming that the Pro Billet using a Hall Effect doesn't really give them much of an advantage over sales or anything alike. Even without the Hall Effect sensor, I'd still buy it just because it is a more rugged replacement over the factory unit. As long as it works and does its job, it's built well.

It's really hard to guess what's inside, and hell no I am not taking apart my distributor when the answer does not make any difference to anyone It's not like Tony1 would buy one if it uses a Hall Effect sensor

On another note, I noticed something really odd when I was setting up an AEM on a buddy's Civic last night. The car previously runs on an APEXi PowerFC but we could not get the car to start with the new MSD Pro Billet distributor. The crank/cam signals are not giving the PowerFC a proper signal and no RPM signal was found. Once we hooked up the AEM, the car fired right up. That is something to think about...hmmm... Now this puts the MSD Pro Billet even more into a mystery...

 

Nice tony

I wish they had this for the d series tho

 

I'm planning on using the crank position sensor on the OBD-II oil pump. The other two will be long bolts installed on my Toda cam gears. On the intake I'll have 4 bolts and have them triggering a mag sensor. The exhaust will have only one bolt for another mag sensor. This will allow for the Honda ecu to get the input needed to process w/o any play on the distributor or the intake cam connection. I plan on later figuring out how to convert to full 4 channel ignition. I think the Greddy emanage can do it but I'm looking for a transistor module to design to do exactly this. I side with Tony on this. IMO, The MSD stuff is junk.

I see a lot of guys purchase used distributors on their cars when they loose spark. Instead of properly diagnosing their problems they resort to replacing the entire assembly. It takes me less than a minute to diagnose their problem with a simple meter like a fluke 88.

I don't understand why someone would upgrade (IMO, downgrade) a distributor to another distributor.

-Joe

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">It's nice and all to have this debate, but I haven't seen any type of VR sensors that would create zero voltage when the power supply (+12v) is off with the magnet passing over the sensor...

The MSD unit would only create voltage at the trigger wires until I cycled the switched 12v to on. Only 3-wire Hall Effect sensors would do this unless I am missing something here...

</TD></TR></TABLE>
From all the one's I've have seem that is correct they need A power,ground,signal out.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">

On another note, I noticed something really odd when I was setting up an AEM on a buddy's Civic last night. The car previously runs on an APEXi PowerFC but we could not get the car to start with the new MSD Pro Billet distributor. The crank/cam signals are not giving the PowerFC a proper signal and no RPM signal was found. Once we hooked up the AEM, the car fired right up. That is something to think about...hmmm... Now this puts the MSD Pro Billet even more into a mystery...
</TD></TR></TABLE>
I think when I call MSD a couple of months ago they offered it 2 ways with A straight Hall signal(square wave) or the converted version, so maybe you had the square wave version.

 

if htey offer one that just has a square wave output then the ems would have had to been modified to work with it

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDogg &raquo;</TD></TR><TR><TD CLASS="quote">if htey offer one that just has a square wave output then the ems would have had to been modified to work with it</TD></TR></TABLE>

Then I wonder why it wouldn't work with the PowerFC?

 

when i installed my msd dis. i had no rpm signal either.im on factory harness and neptune.so i just hooked up the tach wire to the 6a box and works fine.i think it mite need a tach adaptor to recongnize the signal. not to sure.did anybody go on the msd forum or try callin them to answer your ??s

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by swapit &raquo;</TD></TR><TR><TD CLASS="quote">did anybody go on the msd forum or try callin them to answer your ??s</TD></TR></TABLE>

I can tell you right now the tech's aren't going to be able to help you with your questions. The best you can do is talk to an engineer, I'll see what I can do.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">[img]

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Where is your dipstick?

 

Is that your catchcan in the stock battery location? If not, what is that thing?

 

What spark plug wires do you use with it? The distributer plugs are male on this cap, but female on an OEM distributer cap.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Takumi Fujiwara &raquo;</TD></TR><TR><TD CLASS="quote">Is that your catchcan in the stock battery location? If not, what is that thing? </TD></TR></TABLE>

It's a reservoir for my water injection system

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Takumi Fujiwara &raquo;</TD></TR><TR><TD CLASS="quote">

Where is your dipstick?</TD></TR></TABLE>

Right beside the power steering mount... The cutout on the heatshield is where the dipstick is located. I had to turn the oil dipstick tube and bend the dipstick so it would clear the turbine housing. The HKS manifolds puts the manifold pretty close to the block.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dunkd &raquo;</TD></TR><TR><TD CLASS="quote">What spark plug wires do you use with it? The distributer plugs are male on this cap, but female on an OEM distributer cap.

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The package includes a set of connectors and boots to convert either your stock wires or MSD wires to the ones meant for the MSD dizzy.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">

The package includes a set of connectors and boots to convert either your stock wires or MSD wires to the ones meant for the MSD dizzy.</TD></TR></TABLE>

Thanks for that info, now we can complete Cody's order with the wires or he can use his stockers either way. I did speak to MSD twice today and they advised me as did Howard from RLZ Engineering, that you have to use the MSD Coil Part #8235 , it looks to be exactly the same as teh Blaster SS coil BUT it is Black and costs more! I see you showed the pic of the red blaster ss coil, are you using that or the one that MSD states YOU MUST USE? Thanks for any info, I am about to run this set up as well since it has worked well on some cars that RLZ has done as well as JDogg

 

The plug wire ends they use are HEI style or late model GM.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostfed.com &raquo;</TD></TR><TR><TD CLASS="quote">

Thanks for that info, now we can complete Cody's order with the wires or he can use his stockers either way. I did speak to MSD twice today and they advised me as did Howard from RLZ Engineering, that you have to use the MSD Coil Part #8235 , it looks to be exactly the same as teh Blaster SS coil BUT it is Black and costs more! I see you showed the pic of the red blaster ss coil, are you using that or the one that MSD states YOU MUST USE? Thanks for any info, I am about to run this set up as well since it has worked well on some cars that RLZ has done as well as JDogg </TD></TR></TABLE>

I went to a local MSD distributor (Performance Improvements which is the largest store in Canada that sells MSD products) when I purchased the MSD dizzy and ignition module. Well, they better be the largest because even Summit doesn't stock the stuff they do here...haha They stated that they didn't stock the PN 8235 because they are the same as the regular Blaster SS coil, so they told me they would have sold me the Blaster SS coil anyway if I needed one.

I am sure it is the same situation as the MSD 6AL vs the SCI box, Larry @ ENDYN once took apart those two boxes and found them internally identical but the SCI box had a smaller enclosure.

I would have understandably believe that the same importance goes for the ignition module, but for the coil, it seems to be a very universal part. Unless MSD makes a bulletin regarding the significant difference between the two coils, I would lean towards believing that it was a mere move to distinguish their sport compact line up vs their domestic V8 line up

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dragline &raquo;</TD></TR><TR><TD CLASS="quote">when I call MSD a couple of months ago they offered it 2 ways with A straight Hall signal(square wave) or the converted version.</TD></TR></TABLE>

Can anyone confirm this? I dont see two different part numbers for this. Id like to get the digital hall signal output because Im using the AEM EMS, might as well take advantage of the better signal type.

 

Couple things:

1. Tony1 is totally right about standard VR sensors VOLTAGE and frequency varying with RPM. I've scoped this numerous times on stock cars with my scope. There are references to it in most of the electrical troubleshooting literature I have. There certainly are VR sensors that have normalized output so that voltage does NOT vary, but they are a relatively new thing. Laws of physics dictate the variable voltage behavior.

2. AFAIK, the honda ECU looks for the zero crossing of the reluctor signals. Additionally, the sweep of the signal is inverted compared to most other manufacturers. Engine rotation perhaps?

3. Fooling the stock honda ECU into thinking that a distributor is present and spinning on the bench has been done. The first version of the sim used a -5V power output from a computer power supply as well as the usual 0, +5v, +12v channels and an optoisolator for each VR sensor. This approach has been verified to &gt; 9000 RPM on the bench with no CELs. I think there is a simpler way of accomplishing this effectively.

4. If I was a MSD engineer and I wanted to use hall effect sensors but still be able to talk to the stock ECU, the approach I would take would be to use a voltage offset on the negative VR input pin (+5v perhaps?) and run a +12v/GND switching hall effect so effectively the signal being seen by the ECU would be -5V -&gt; +7V. Point being: this isn't all that tricky of a problem to solve because the ECU concerns itself primarily with zero crossing and signal-signal synchronization (among the 3 reluctors - note: based on the code they run, this is my guess as to why honda ECUs like honda distributors more than AEMs and other standalones).

Bottom line: a scope and 5 minutes of time should answer a lot of questions.

Things I would be looking for:
1. Shape of signal
2. Voltage output levels at idle
3. Voltage output levels at 4000 (or any higher RPM)

 

soon as we get the car in the shop running again i can hook up my scope to it and see wtf.. i can also do some logging w/the ems and do some comparison w/the stock dizzy mess and see wtf is going on.

i do know the timing signals are much cleaner w/the msd dizzy when using an ems, timing light is much more stable at idle and at higher rpms than it is w/the stock dizzy

 

blundar, we should meet up and you can scope me....i mean scope the car

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDogg &raquo;</TD></TR><TR><TD CLASS="quote">soon as we get the car in the shop running again i can hook up my scope to it and see wtf.. i can also do some logging w/the ems and do some comparison w/the stock dizzy mess and see wtf is going on.

i do know the timing signals are much cleaner w/the msd dizzy when using an ems, timing light is much more stable at idle and at higher rpms than it is w/the stock dizzy</TD></TR></TABLE>

Yes, that's what I noticed as well, and getting the car to idle like stock is not even a challenge anymore...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blundar &raquo;</TD></TR><TR><TD CLASS="quote">Couple things:
2. AFAIK, the honda ECU looks for the zero crossing of the reluctor signals. Additionally, the sweep of the signal is inverted compared to most other manufacturers. Engine rotation perhaps?

</TD></TR></TABLE>

if this is true then this makes sense now as to how the stock ecu can interprit the signal from the msd hall-effect. The hall effect just gives a digital 0 1 ( as the magnetic field contracts and expands) signal and since the computer is programed to look for 0v and ignore everything else in between it all works out. For people who will use a scope please do so on all three pickups. let us know what you find out.