Ok so I have a better understanding.

As I said I have the EFI Quadspark and Tower 4 coil coming and it shows a configuration like what is shown below.

Click to view attachment

I think the SPK C and D requires a cam position sensor to use.

But I should be able to use just SPK A and B to fire each side of the coil

But because the firing order on this is 1, 4, 3, 2 I am not sure how to configure the wires?

Looks like I would have to fire 1&3 together. 1 would be at firing position and 3 would be the wasted spark on the exhaust, and next 2&4 together?

I recommend this coil, same one we just used on the 2270 build. Super easy with the built in igniters. Only thing to be aware of is the firing order difference between the inline 4 VW motors this comes off of and and type 4 firing order. You will need to swap the cylinder 3 and 4 plug wires from how they are labeled on the coil in order to get the banking correct. Wasted spark on a 4 cylinder only needs two spark outputs. No need for the quad spark or external igniters if you are using a logic level coil.


As far as your head temp situation, given you are running a stock cam with a large displacement engine and a stock distributor for timing control, I would expect your head temps to be over 350 most of the time and probably pushing 400 on the freeway and hill climbs. Also retarding the timing may actually be making the temperature situation worse. Best situation you could probably hope for with your current setup is to set the distributor timing to spec or maybe even advanced beyond that a degree or two and make sure you are not running leaner than 13.5:1 anywhere in the map. You could try to richen it up a bit in the areas you are running hot (possibly all the way to 12.5:1) but without programmable timing control that is about your only option at the moment.

Also, I would bet money that you have some holes in your cooling tin that are missing their proper plugs. If you see any opening in your tin at all there is something that is supposed to be sealing it. Not going to make a huge difference but every little bit helps. Most common ones I find to be missing are the seal around the oil pressure switch, the seal around the head temp sensor opening, and the ones that always seem to be missing, the ~1/4in holes for the spark plug wire clips. If you dont have all the proper hardware for your heat exchangers you should plug those lower holes in the fan housing too. Even with everything in proper order though 350+ with that displacement, cam, and distributor shouldn't shock you.

There are a number of cooling tin issues. First it was modified for AC so there are some leaks! But sound advice.

Been able to run in the 12.5 range and have seen some dramatic drops in temp. On highway at 70 - mpg 340 and never above 385 on hill climbs.

Should start putting in the new coil next weekend!

But I was thinking that my O2 sensor could be in the wrong place. It is currently located at the end of the exhaust pipe after the muffler. I am wondering if this is potentially giving me bad readings?

Those temps are looking good for your current setup.

Having the O2 sensor after the muffler in the tailpipe is not the ideal location. Depending on your exhaust there is a chance it could be reading slightly leaner than it should at lower RPMs. If anything it may be adding some delay to the sensor response. I like to put mine as near as you can to the collector, as close as possible to the heads but after all 4 pipes are tied together. I wouldn't delay any other progress on moving that sensor though. Its been working this far, consider moving it as a future improvement.

You are going to love the wasted spark once you dial it in!

I like the simplicity of the cost effective option shown on post #98 (VW coil). Do we know if this coil will accept the regular 914 ignition cables or it will require 99-01 Golf/Jetta ones? I recently bought a nice set of Magnecor cables and would like to keep it if I were to do a MS upgrade.

I am also running a 2056 (DJet) and getting these type of head temp mentioned.

I know the usual route for MS upgrade is induction, then ignition but could one begin with ignition while keeping the D-Jet for induction, then upgrade to full control?

Like your MS build thread, I have been enjoying this one as much and looking forward to your ignition one. Great achievement!

My understanding is it will work with stock wires. I will verify when it gets here and post.

With the 2056 and D-jet you have to add more fuel than you think. I know there are all of these "ideal" values. But you have to control the head temps. Timing is a good place to start but don't be afraid to run richer than you think is necessary. You can always back it out but too lean = hot running engine regardless of what the number on the AFR is.

I started with fuel only first because i thought it would be easy enough to trigger off coil. Bottom line is that approach is not the best and if you are going to add a tigger wheel I highly recommend McMarks set up. Absolutely flawless on the install and operation.

I found the coil on Amazon for $18. I also have the DIY Auto Tune high power coil coining as a back up. But I am going to try the low cost approach first. Simple install and low cost is very appealing.

I have learned a lot during this process and had the input and assistance of some really great people. I hope this does help some others that are heading down this road.

As i have said, i have my D-jet and will keep it intact. But for me at least, the D-jet is just very difficult to adjust for any engine modification. After running hard at Okteenerfest and many drives after I know for a fact that the engine feels like it is running stronger and while I have no way to measure that, not having any problems with the system and having it just work under all conditions is enough to justify the conversion even if the perceived performance increase is just in my mind.

I will work with McMark and some other vendors to come up with a price list for the conversion so that people can see the actual costs. I got a little beyond my orginal intent to do this for less than $1,000. But I and confident that both fuel and timing can be done for this price or less.

A few preliminary things done. Coil and test wiring ready. Stock plug wires won't work with this coil. Will have to buy some VW ones and adapt.

Click to view attachment

A lot of the cables offered for the 99-01 VW 2.0 have metal sleeve at the spark plug. I did see some blue ones with rubber sleeves where it might be possible to slide over the rubber washer to seal the shroud.

I saw on ebay some pigtail to connect to the coil. This is an example, I'm sure there are cheaper ones.


Click to view attachment

I don't understand what the QuadSpark unit is doing for you. The MicroSquirt can directly drive a coil with built in igniter. So why add the QS unit? Am I missing something?

The other coil from DIY is a high energy unit with out igniters. So the Quadspark is needed with it. I am using the $18 coil with built in igniters to test everything first and will switch to the high energy coil at some point.

I order a couple sets of cheap ones and will hopefully modify those to work. The DIY Autotune coil that I will switch to after proving everything out should work with the stock wires.

Depending on how this coil works I may add the pigtail if I run it long.

Ignition power is only relevant if the spark plug is failing to ignite the mixture. If the 'cheap' coil doesn't give you any performance issues, then increasing the spark power won't add anything.

The job of the coil, wires, and spark plugs is simply to ignite the air-fuel mixture. Starting a campfire with a match isn't better or worse than using a jet-flame lighter. The in some cases the lighter is 'better', but it doesn't increase the 'performance' of the campfire. Now that I think about it, that's a great analogy. If the match is blowing out (and this CAN happen to a spark plug) then you need the jet-flame lighter to overcome the issue. But if there is no issue, the lighter doesn't add anything and it's potential is wasted.

In case you're still looking at a low-budget build, or want to avoid possible complexity/issues from more components.

I could very well be wrong on this, but that's somewhat contrary to what I've always been told.

I thought that more power through the coil allowed the use of a larger plug gap. Larger plug gap gives a larger flame front at the point of ignition, and also gives faster ignition to the air fuel mix, which gives the fuel more time to burn, which allows more of the fuel to burn, which is your efficiency increase. Same theory as using twin plugs (which are even more efficient as they start 2 flame fronts, instead of just one bigger one.)

To use your example, using a match will get your campfire lit, but I bring a MAPP torch becasue it lights the fire a hell of a lot faster, and is more tolerant of damp wood, wind, rain and other things that will slow down ignition.

Zach

Absolutely true.
It gives a larger spark length, but not necessarily a larger flame front. Flame propagates much like a balloon or bubble, with the spark at the center. Increasing the size of the origin of the flame kernel won't make the kernel bigger. Instead I would say it gives more opportunity for ignition in turbulent conditions.
I'm pretty confident that's wrong. I'm pretty sure flame propagation speed is fixed based on things like RPM, compression, overlap, swirl. I don't know of anything you can do to the ignition system that will increase the flame propagation speed (aside from twin plugs, which isn't even increasing flame speed either, it's just starting two fires at the same time and letting them expand toward each other).
Not the same theory. Two flame fronts is WAY different than one.

Maybe a better example is if you had a 1 acre field of dry grass. (no wind, or other outside forces) If you were to ignite the field in two places, 2 or 3 or 4 or 10 feet apart, the field would burn at roughly the same rate. But if you ignite the field from opposite sides, then you can clearly see that the total burn time would be far less.

My understanding is that there are two common issues that ignition systems encounter:
1. Low RPM instability: At low rpm the air-fuel mixture is moving fairly slowly. There is less swirl in the combustion chamber, there is less efficiency at low RPM so you're not getting reliable exhaust expulsion nor intake suction. The fuel has more time to fall out of suspension and form droplets.
2. High Compression instability: At high compression ratios it's harder for the spark to jump the gap because of the density of the air (maybe you could say there's more air molecules that the spark has to push past). Also, on turbo applications (maybe high compression motors as well) there is a possibility for the higher charge swirl (turbulence) to literally blow out the spark like a candle.

Low RPM instability can cause misfires if the spark event happens at an inopportune time, when the swirl effect has just happened to pull the fuel particles out of reach of the spark. Especially at low RPM the air-fuel mixture is NOT homogeneous. There are areas of greater and lesser AFR. If the spark plug fires when there's no fuel around, it misfires (no ignition). Adding length to the spark would mildly improve the chances of avoiding that situation. Multiple sparks on one plug greatly increase the chances of avoiding that situation by trying multiple times, one of which is likely to catch. Twin plug will also greatly increase the chances for ignition. Simply increasing spark voltage will do nothing to increase the chances of ignition. Remember there is no such things as a 'hotter' spark.

High compression instability is clearly a case for increasing spark voltage. If the spark plugs are failing to fire because of charge density, increasing voltage will absolutely increase the reliability of the spark jumping the gap. If the spark is being blown out, a higher voltage will add stability to the arc in those turbulent conditions.

The KEY to all I'm saying is that if a basic coil is igniting reliably, increasing anything in the ignition setup won't do anything (aside from multiple spark).



Okay, the campfire example isn't perfect. But "damp wood, wind, rain and other things" would be examples of factors that make igniting unreliable and would therefore be example of when my assertion recommends upgrading ignition components.

Actually, more thoughts on this if you needed more convincing that the flame propagation speed is fixed. Consider that the entire reason that we have to increase spark timing (advance) as RPM increases is because we need to ignite the mixture earlier to give enough time for complete combustion to happen.

If we could increase the flame speed by increasing the voltage from the coil, we would have engines with fixed distributor timing, and variable coil voltage. Because controlling coil voltage is a HELL OF A LOT EASIER than designing a centrifugal advance distributor.

Use the analogy of a bucket of gasoline. It doesn't matter if you throw a small match into it or a large match, once there's ignition it's ignited. Or maybe better if you poke a small needle or a big nail into a balloon, the bang's going to be exactly the same. Only time you'll have an advantage from a lager spark is in extremes like very high RPM's, or extreme swirl from forced induction, those kinds of things.

While all of this is true, the one true benefit of a high engery coil is that it actually does have the ability to overcome resistance that is inherent to the system. As the engine and electrical system gets hot the resistance the flow of electricity increases. Higher energy coils do limit the degregation of the spark due to resistance.

I have objections, but I suspect I'm annoying at this point so I'll bow out.

You're certainly not going to hurt anything by throwing more voltage at it.

You have no idea just how much information you provide to others in these discussions. No need to bow out.

You are spot on most of the time and discussion is what moves the understanding of those of us that don't do this every day forward. Thank you for that.

High engery coil turn the 914 into a 10 second car? Certainly not. But it has its application as long as your expectations are in line with reality.

Okay, I wrote a few different replies and deleted them all. I'm going to step out of the theoretical and just talk about your setup.

The VW coil you got 'temporarily' will give you everything you need.
The QuadSpark setup will allow you to run a larger spark plug gap, and that will improve your idle, but everything off idle will stay the same.

I jumped to the end on my phone. Are you still trying to use the 3 bar map? If you are not boost, you should really only use the stock 1 bar. I use a 3 bar on my lsx because i will be boost. Show me your map values for thst 3 bar. If that is not right everything will be off.

Yes still using the 3 Bar but with a linear calibration of 1.1 kPa at 0 volts and 315.5 kPa at 5 volts it should read the normally aspirated range?

Ill take a look am on my tuning laptop

It will read the ambient pressure range, but with less than optimal resolution. Might not be a big deal since you're not tuning to the nth degree, but I personally would change it out.

Yup, it's a matter of resolution.

If any MAP sensor give you say 100 'steps' or readings, then a 3bar MAP sensor will give you 33 steps for NA and 66 steps you don't ever use.
A 1bar MAP will let you use the whole 100 steps for NA.

It's more righter more of the times.

Good point.

Ordered.

Anyone need a 3-bar?

the 3bar gives less resolution, and you probably did not need it. you still need the right scale and offset for any map sensor. e.g. these are the GM settings for hp tuners....

GM 1 bar map sensor Linear and offsets for HPtuners software
MAP Sensor Linear: 94.43
MAP Sensor Offset: 10.34

GM 2 bar map sensor Linear and offsets for HPtuners software
MAP Sensor Linear: 207.66
MAP Sensor Offset: 9

GM 2.5 bar map sensor Linear and offsets for HPtuners software
MAP Sensor Linear: 244.68 kPa
MAP Sensor Offset: 10.21 kPa

GM 3 bar map sensor Linear and offsets for HPtuners software
MAP Sensor Linear: 329.41
MAP Sensor Offset: -6.35

GM 3.3 bar map sensor Linear and offsets for HPtuners software
MAP Sensor Linear: 333.33
MAP Sensor Offset: 33.33

So you should be able to get it to fire and take the pedal without the finer resolution.

I always thought the MAP readings were a bit "vague" at times. Ran well and responded well to changes in tune but having better resolution in the engine operating range has to be better.

Tuner Stuidiods has slightly different values built in.

OK should be a good weekend. Going to change over to the 1 BAR MAP and to controlling the timing with the ECU!

I am going to simple way first. Click to view attachment

However I was just wondering if I am missing something in Tuner Studios regarding IGNOUT2.

As indicated in the setting below there is a place to select IGN 1 but there is nothing about 2.

Click to view attachment

Does the ECU just "know" when to fire the other bank ore is there a setting I have enable?

Quick question McMarK. I am assuming this photo is at TDC?

I think once you run it you will realize you don't need anything more than the simple way. Its already so much more than what the stock system was and the less hardware and wiring to mess with the better.

Other than the settings for your trigger wheel (which you need to confirm with Mark given its his wheel) your output settings look good for that coil. With "number of coils" set to "wasted spark" IGNOUT 2 is enabled automatically. I don't believe the secondary output channel is customizable in software. Yes the ECU knows which bank to fire as long as you have the missing tooth angle set correctly so it knows where TDC for cylinder 1 is.

Be sure you check the tooth angle setting with a timing light once it is going. When running fuel only angle doesn't matter only engine speed, so it could be set completely wrong but working fine until you try and fire a spark with it.

Well this cant be good. Did a temporary wrire in of the coil and plugs for testing.

F$%king started first time! Smooth great idle and all seems good. I must rip it out and break something so it will be harder! I am confused when I am not banging my head on the wall. Pretty amazed at the ease of the conversion.

Will have to get a dizzy block off from some where McMark?

Checked time with light and it seemed close. Will have to mount up everything and put the actual coil wire connector on when it comes in.

Anyone got an existing mounting bracket for the tower coil?

Idle is too high now as I think my existing throttle body was designed to have negative advance at idle. Anyone know a solution other than plugging the small hole in the throttle plate.

I guess i can plug in negative advance into the ignition table at idle speeds? Throughly checked for vacuum leaks and have none and was able to idle great using the negative advance settings on the 123 dizzy.

Crap I like this! Plugged in -10 advance at the idle MAP and speed and instant 950 RPM!

Did not turn a single bolt on a dizzy or get out the timing light. Just used my button finger.

Not sure if that is the right way to address the problem but it works.

If you ever consider doing this the Bluetooth is a must. I think the Bluetooth unit was like $60 and I am using a $100 android tablet most of the time to make changes with MSDroid. Very nice. This set up has saved me far more time than the $160 it cost.

Nice work Mike I'm watching your thread very closely as I intend to do the microsquirt soon. Have to save some pennies up first. So maybe February? So that means you're going to come out and get it dialed in for me right?

Love Oregon so that is possible. Yes I think this can be done fairl cheaply and I kind of got away from that but the reality is that other than the ECU so many of the parts are vet cheap. I got the coil for $18 and just got a 1 bar map for $20. I will work on getting a parts list and cost together.

You are idling at 10 deg after TDC? If so something aint right.

Before you do anything else tuning wise you need sanity check your trigger wheel settings with a timing light. Temporarily enable fixed advance from the wheel decoder page and set it to whatever your timing mark on the fan is at, or if you have an adjustable timing light you can mark TDC on the fan and set the fixed timing to whatever you have your timing light adjusted to. If its off you need to adjust your missing tooth angle to correct it. It should be more than close, with the setup you have it should be dead on, rock solid like nothing you have ever seen on a 914. Be absolutely sure you know what the markings on your fan are at, verify against the flywheel TDC mark.

Once you are absolutely sure the timing displayed in Megasquirt matches what you are actually getting you want to adjust your timing at idle to obtain the maximum manifold vacuum and then retard it a few degrees from there. This will give you the strongest idle and best off idle throttle response. Your idle is probably going be somewhere in the 8-15 deg BTDC range setting it like this. If you cant get the idle speed down with the timing set in this manner then you have other issues that need to be addressed. Dont adjust your timing to bring down your idle. You don't want to be idling 10 deg ATDC this will cause your exhaust (and most likely heads) to run hot as well as give you a weaker idle and sub par off idle response.

Timing is the most critical thing to get correct. In addition to possibly damaging your engine if you get it wrong, getting it correct and dialed in is where you are going to see the performance gains.

If your throttle body is stock and unmodified check you Aux Air regulator, and PCV. whenever i see an idle that cant be adjusted down on a car with a stock intake setup its usually one of those two things is broken/stuck open. You should have no problem adjusting idle speed properly with 8-15 deg advance if everything is working correctly.

Also, remember you will need to re-tune your fuel map once your timing table is set. Changes to the timing impact the engines efficiency/fuel needs.

Almost forgot



http://thedubshop.goodsie.com/hex-distributor-plug

They have a vented plug with an AN fitting as well if you wanted to go that route for extra case venting.

thedubshop has pretty much everything you would need when it comes to Megasquirting VWs/914s. Best to not browse around on that site to much otherwise you start getting ideas...

You've already passed the need, but yes, my picture is a TDC (roughly).

I think I still have your address. I'll send you a block off plug.

with James, confirm the timing by enabling FIXED TIMING. That's CRITICAL. Do nothing else, until the laptop/computer and what you see with the timing light matches.

Also, as James mentioned, you may have air leaks in your intake system if the idle stays high once the timing is correct. You should be around 12degrees BTDC by the way. If your idle remains high, start checking for leaks.

Vacuum based injection (MAP-systems or D-Jet) doesn't have a problem with air leaks. Air leaks change the manifold vacuum and the FI compensates for the extra air because of that change in vacuum. Newer FI will run lean if there are air leaks. Not MAP/D-Jet, they just use the air and you notice a high-idle issue.

This is applicable to anyone running D-Jet or MAP-based FI: If you can't kill the engine by closing the idle bypass screw on the throttle body, then you have air leaks.

Have to get the coil plug harness in as it is just a temp setup for testing the electrical part. Did brief check admittedly not extensive of the timing and it seemed to be very close. Changed table at idle to 0 advance and saw only the TDC marking. Will follow your check process.

No AAR or PCV. Running case vent and head vents to oil catch can and then to breather. Fairly sure I have no vacuum leaks. I can cover the throttle body and it dies instantly. I have sprayed, checked, and listened countless times and can not find any leaks. That does not change what you stated and I do need to verify the timing further and recheck for leaks.

Will do that and report back.

Love the Dub Shop but because McMark / Original Customs did my engine and supplied many of the FI conversions components seems to be necessary to use his.

I get it, good to stick with the people helping you out. I didn't know mark was producing these.

Really curious to see what you find out regarding the high idle.

OK So I followed James direction.

Enabled fixed advance from the wheel decoder page. Set to 0 which should give me TDC on the timing light. This was off so I adjusted the Tooth angle for #1 BTDC from 60 to 72 and it showed the correct timing mark dead in the slot!

Enabled Use Timing table and at idle it seem to indicate the right value of 9 to 10 degrees. On bumping up the RPMs the marks advanced in the correct direction toward the 27 degree mark but fell just short of the mark. The table was set to 27.

Revising the table to 30 brought the impeller wheel 27 degree mark into perfect alignment. A bit confused by that so I will recheck it tonight and try to get a video.

Based on each tooth on the trigger wheel being 10 degrees I was a bit perplexed by the 72 value getting the TDC lined up so that is likely where I am off as on the total advance. Just did not have the time to go back and recheck last night.

If anyone needs a wire connector for this VW coil I have 3 extra!

Try doing this with it set to 12 degrees now that you're closer. The engine probably won't idle very well at 0. Check for 12 degrees fixed on the computer, and tweak the offset angle till you see 12 on the timing light.

OH! And make sure your timing light is compatible with wasted spark!!

OK I picked 0 because it had a exact measurable point on the impeller. There is no 12 degree mark. I have the simple timing light that works with wasted spark. No way to set the offset.

I guess I could back in to it from the 27 mark as well as another check.

Pelican has a nice write up with a template for the timing on the impeller.

http://www.pelicanparts.com/techarticles/9.../914_timing.htm

http://www.pelicanparts.com/techarticles/9.../914_timing.pdf

That'd work. Just adjust your timing table until EVERYTHING above 3000 rpm is 27° and then use your timing light to check the timing like a stock 914. Rev up past 3000 and see if the mark is there. Adjust as necessary.

Got a very undeserved but much appreciated gift from a true master. Thanks to Orginal Customs and McMark for a work of art.
Click to view attachment

I wonder if they make one that has a cam sensor?

I dont know if Mark does, but yes they do exist.

http://thedubshop.goodsie.com/mini-cam-sync

I have always felt like going full sequential on a Type 4 may be overkill but that is a configuration that I have not tired myself so i cant say for sure. I can say batch fire setups run so damn good i dont know if I would be able to notice a difference.