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Sat Aug 13, 2011 8:10 pm

Piledriver needs to chime in here, but as I understand it the distributor rotor spins twice as fast as the crank. Might be as simple as telling MS you have twice as many teeth.

my setup is one of the cheapest since the COPs are dirt cheap on ebay, but you need to add coil drivers. I think it's jaguars and LS1/2 COPs that use short stalks and are self igniting so they would be a bit simpler to do.

Keep in mind there are ways to connect the coils to the plugs too. I am using mazda miata bosch spark plugs, since they have the same size and length threads but the skinnier 5/8" socket and thread off cap on the end for the coils.

I'll PM piledriver and have him drop some smarts on us, piledriver has a type 4 in a squareback with a wilder setup then me as far as MS goes and he is a lot more smartened up then i am on MS too.

Sat Aug 13, 2011 9:31 pm

Hey! you seem to be doin fine.

To run sequential/COP you need TWO triggers, waste spark just needs a missing tooth on the crank.

The distributor runs at half speed to the crank, you CAN run waste spark or even sequential off a modified or adapted distributor, (with a second TDC#1 sensor)

... but running the timing off the distributor adds some variation in your timing that crank trigger is supposed to avoid, and low tooth count wheels can cause some weird when cranking or at low RPM.
(The sync pulse off the distributor is not used for timing calculations, only as a logical flag that "next tooth is TDC#1, and yes, the documentation is wrong)

The minimum practical missing tooth wheel for a 4 cylinder is 4-1.
You can also run sequential on that with the addition of a second trigger for sync.

You only need 36-1 for EDIS: EDIS at one point early on was the ONLY way to go crank trigger with MS, that has not been the case (or even the recommended way to go) for ages.

MS1 supports a LOT of tooth configs, MS2/3 support many, many more, and is far more flexible.

I prefer the LS2 coil setup, gets all the ignition noise out of the computer, and while not as cheap as the GSXR coils etc are still not bad.

It's all pretty well documented here:
http://msextra.com/doc/index.html

Sat Aug 13, 2011 10:22 pm

OK I have a wheel I got from a friend who machined it. It is 60-2, but instead of teeth it has steel pegs pressed into an aluminum wheel. He designed it to fit on the front (case side) of the large fan on the type 3. Sounds like this would be usable with the MS2 or 3 setup? Any idea what I would need for a sensor?

Sun Aug 14, 2011 12:01 am

KevinR wrote: OK I have a wheel I got from a friend who machined it. It is 60-2, but instead of teeth it has steel pegs pressed into an aluminum wheel. He designed it to fit on the front (case side) of the large fan on the type 3. Sounds like this would be usable with the MS2 or 3 setup? Any idea what I would need for a sensor?

You could use most VR sensors, or preferably a Hall sensor for a VW/Audi that uses a 60-2 wheel. (fewer potential noise issues/no additional circuitry other than a pullup resistor required)

AFAIK 60-2 is supported by all MSx-extra versions (MS1/2/3)

At very high RPM a MS1 might have issues with a 60-2 wheel.

6 teeth work just fine, although timing jumps around when cranking, 12-1 would probably be a "easy to make/works great" compromise.

Holes are as good as teeth, and a lot easier to make.

Sun Aug 14, 2011 1:25 am

Cool, sounds like a good start then. Was afraid I would not be able to use it. Have to figure out a way to get the sensor inot the fan shroud...

Sun Aug 14, 2011 4:13 am

Another novice question: If I am not running fuel injection, is there any reason to go megasquirt vs. megajolt? Seems like added complexity that may not be needed or wanted.

Sun Aug 14, 2011 7:49 am

KevinR wrote: Another novice question: If I am not running fuel injection, is there any reason to go megasquirt vs. megajolt? Seems like added complexity that may not be needed or wanted.

Not going to `dis Megajolt, it's a fine ignition system based on EDIS, and depending on your shopping skills and only want to buy pre-built hardware, it will probably be *cheaper...

I have no direct experience with it, but have also never heard anything BAD about it, which is ~amazing if you think about it.

...*Cheaper IF you are certain you will never want to add some injectors and a serious fuel pump.

You will never again have any desire to rejet carbs once you have used TunerStudio's VE analyzer and have it fix your fuel map in real time as you drive around.

MSextra (in it's various flavors) can do a whole lot more, two step, flat shift, shift lights, fan control, boost control/ALS, traction control... and ...MANY more features than I even have a desire to play with.

If you don't want the features, it's easy to turn them off, or if you build your own board, leave off the extra parts.
(makes changing your mind later hard when you cant find that frakking baggie tho)

Sun Aug 14, 2011 9:22 am

Kevin initially I was going to just do the megajolt/EDIS. I bought the unit and of course changed my mind. I still have the megajolt box thats never been used. I am glad I changed my mind because I ended up going EFI first and am working on getting the square on ignition control.

Sun Aug 14, 2011 10:38 pm

OK I am considering going wasted spark instead of MSD. What would I really need to get set up? I am sticking with carbs, so can megajolt run wasted spark, or is it strictly edis? If I need to get megasquirt, can I set it up with a rev limiter?

Sun Aug 14, 2011 11:05 pm

KevinR wrote: OK I am considering going wasted spark instead of MSD. What would I really need to get set up? I am sticking with carbs, so can megajolt run wasted spark, or is it strictly edis? If I need to get megasquirt, can I set it up with a rev limiter?

IIRC megasquirt lets you program in any rev limitation you want, or none at all.

Mon Aug 15, 2011 1:18 am

I am a bit concerned about costs and complexity with megasquirt vs. megajolt. My friend Duanne runs EDIS on his bug and it is sweet...

Looks like a ready-built megajolt box is about 165.00 or so, while a ready-built mega-squirt is over 400.00. I WAS an electronics tech in the Navy, but have not touched a printed circuit board in over 20 years, so I am concerned about my ability to build the megasquirt kit succesfully. (said kit is still more than the assembled megajolt).

Anyone know if the megajolt can have rev limiter function? I am not a drag racer, but a rev limiter is cheap insurance...

By the way, I started an engine build thread in the performance engine forum for the 1956cc motor I am building.

Oh, one last question: Just how precise do the teeth on a trigger wheel have to be? Am considering making my own, I have a drill press, but am no machinist.

Mon Aug 15, 2011 7:50 am

KevinR wrote: I am a bit concerned about costs and complexity with megasquirt vs. megajolt. My friend Duanne runs EDIS on his bug and it is sweet...

Looks like a ready-built megajolt box is about 165.00 or so, while a ready-built mega-squirt is over 400.00. I WAS an electronics tech in the Navy, but have not touched a printed circuit board in over 20 years, so I am concerned about my ability to build the megasquirt kit succesfully. (said kit is still more than the assembled megajolt).

Anyone know if the megajolt can have rev limiter function? I am not a drag racer, but a rev limiter is cheap insurance...

By the way, I started an engine build thread in the performance engine forum for the 1956cc motor I am building.

Oh, one last question: Just how precise do the teeth on a trigger wheel have to be? Am considering making my own, I have a drill press, but am no machinist.

I was a FC in the navy back in the 90's, you'll be just fine assembling a MS. here's the detailed assembly instructions for a v3.00 pcb http://www.megamanual.com/index.html. You just need to know how to solder and follow directions. here is a vid of a dude who put a srt4 motor in a minivan, lol.

he explains the launch control, rev limiter is similar.

Mon Aug 15, 2011 2:31 pm

Alright, to all that is interested, I have placed an order for a prototype of the trigger wheel. It shall be at my door step within several weeks. I'll report back with pics and install pics.

One thing i'm worried about is the accuracy of mounting. Since i'll be drilling and tapping the fan wheel, there is a possibility of the trigger wheel being mounted slightly crooked. This is when a jig and a drill press will come in handy to make accurate holes.

Mon Aug 15, 2011 3:02 pm

The teeth being perfect is "important", but avoiding runout is vital.

Mon Aug 15, 2011 3:07 pm

I am thinking of mocking up my own 1-off wheel with holes instead of teeth. Anyone know what diameter the holes would need to be?

Mon Aug 15, 2011 3:14 pm

here you go kevin:

http://www.megamanual.com/ms2/36-1.htm

Mon Aug 15, 2011 4:02 pm

So, the holes and areas between would have to be about the same size as the sensor... hmmm may just wait for one of your wheels!

Mon Aug 15, 2011 7:11 pm

supersuk wrote: Anybody interested in a trigger wheel for a megasquirt ECU specifically made to use on a Type 3 pancake motor? I have designed one that will fit onto the pulley with very little modifications. All you need are 4 bolts, 4 washers, a drill bit and a tap.

I'm going to have a shop make some for me, but if I bought just one the price is crazy! However, if a lot of people jump in with me it'll be a lot more reasonable.

The trigger wheel will mount to the front face of the pulley without blocking the fan. The mounting points will be where you see the small holes on the outer ring of the pulley. Just drill and tap the hole to fit a bolt. The trigger wheel itself will have 4 slots 90 degrees apart and can be adjusted about 20 degrees total. The VR sensor will be mounted through the timing hole on the black fan shroud.

G'day supersuk. Just noticed your post about the trigger wheel. I would definitely be interested in one. I've been looking for a decent solution for this issue and like the idea you have come up with.

One thing I might suggest is to remove some material opposite the missing teeth on the inside of the wheel to help keep the trigger wheel balanced. You will need to remove exactly the same area of material as the missing teeth, and also diametrically opposite. The material does not need to be the same shape, only the same overall area (eg weight)

You also do not need the slots as the wheel position can be set up in the software. By removing the slots you also have less chance of the wheel moving which is much better IMHO.

Have you considered laser cutting? It's relatively inexpensive and if you have the wheel in 2D CAD (DWG) format, you should be able to email the file to a laser cutters and they will cut one out for you. Last time I did this it cost about $40 for a part this size in stainless.

Regards.

Mick.

Mon Aug 15, 2011 7:18 pm

Just whilst I think of it. The sensor position might be better directly in between the crank and generator - the reason being is that if yo mount it where you are suggesting, it makes changing the fan belt a lot harder.

Mick.

Mon Aug 15, 2011 7:57 pm

Mick, I have thought about installing the trigger wheel behind the pulley but there is no easy way to mount the trigger wheel without having a jig made. Most DIYers will prolly mount it crooked.

As for the slots, they are needed to mount the trigger wheel to the pulley. Bolts will screw into the existing holes on the pulley after they are drilled and tapped. Every pulley is different and have counter weights pressed into the holes on the face of the pulley. The counter weights will vary from pulley to pulley. The final revision will have 8 slots to account for this.

As for the balance, this has been taken care of. The dwg that I showed was an initial version I drew up to gain interest.