F355 coil-on-plug conversion

Not sure what the deal is on the the tach adapter , It looks just like asmall ignition coil or a choke. It goes in between the trigger signal wires .
All I have to donow is pretty up the wiring , looks like raido shack blew up under my hood . Iam going to cover teh wires with a silcone covered fiberglass , It looks just like the black tube ferrari uses on its harnesses but if good for 650 degrees , Jeff have you had any trouble with the wires melting near the cops ?
Do you by any chance have a drawing or the G-code for the spacer you made .
I need one thats about .125 inch high , got close but the plug went over like you said . I have a cnc mill so if you have the code or the autocad it would be grate .If anyone in the chicago area needs help with this or want too see it let me know , Like Jeff said this is the way to go . The money you save from buying sparkplugs from Ferrai is worth it .

 

If any one is interested in doing this conversion I have a complete setup that I was putting together at the same time as mine for my uncle . He has decided to trade his 355 in on a 360 , So IAm stuck with the whole kit . The harness is complete and has the cops and sparkplugs , Dis-4 was used just to test it .
I will sell it for what I have into it if anyones interested .All the hard work is done should only take an hour to install .

 

Bill-

I am interested. Can we meet up to check out your setup? I'd like to get a first hand look at how effective it is.

I'll be out of town Friday-Sunday at Mid Ohio, but I'll be available anytime after that.

 

Hello all,

Just got done installing the COP conversion on my '99 355 F1, and I thought I'd share my experience. I was so intrigued by this conversion, and at the same time annoyed by the rough idling and subsequent rough take off from standstill, that I went ahead and did the conversion.

I took the easy route, though, by jumping on Billwann's offer on a duplicate kit he already had put together. What a great guy to deal with, and what a well put together kit he had. Thanks, Bill!

It went together quite smoothly, taking my time taking things apart, cleaning each item before putting it back together. I fabricated a couple of mounting brackets for the DIS-4, and mounted it on the rear passenger side of the engine compartment. The rest was pretty much plug and play, as the harnesses were already put together with brand new connectors and high temp silicon sleeves. Checked and rechecked the settings on the DIS; set at WS+4Krpm (setting #3), and deactivated retard and set the rpm limiter to max. Oh, and the COPs Bill supplied were short enough that the spark plpug covers fit right on (albeit a bit tight) without use of spacers.

The first time I attempted to start it up, it didn't fire up. On the third attempt, the engine fired up, but it ran VERY rough, as if only one half of the engine was firing. There was the smell of unburnt gas. Shut it down right away, I checked and rechecked everything. Finally, I found one of the pins at the DIS connector dislodged in the socket, not making proper contact. After fixing that, the engine fired up right away and soon it was idling smoothly.

Time for a test drive... first time I took it out, there was some hesitation between 4-5K rpms, while in WOT to redline. After driving for a few more minutes, that hesitation moved up to around 6500 rpms, and it stayed there for the rest of the semi-spirited drive. Back to the garage to think about what is going on.

I delved into the DIS-4 owners manual, and found something in there that suggests the wasted spark setting *might* not be needed in our setup. It says in there that if the DIS is installed on a 4-cylinder motor with individual coil packs, we need to set it to the non-WS setting. I am thinking, the DIS right now does not know it is connected to an 8-cylinder motor, as it is getting a 4-channel signal from the ECU, and outputting a 4-channel signal to the paired COPs, as if powering a 4-cylinder motor. What do you guys think of this logic?

Anyway, I tried setting the DIS in a non-WS setting (all other settings the same), and the engine started up normally and idled smoothly, no difference there. But upon driving it, there was noticably rougher, and the engine was cutting off at just before 7K rpms. But there was no hesitation. So back to the garage.

I set it back to the original WS settings, and just for the heck of it, I drove it out again. Lo and behold, the hesitation dissapeared! Power is smooth to redline at WOT, idle and take off is smooth. I am happy! There is one more glitch, though. At crusing, part throttle speeds, there is still some roughness, and the rpms tend to wander. It is more noticable in lower gears. It disappears when I either lift off the gas, or floor it, then it accelerated smoothly to redline.

What could that be? I have the spark plugs gapped at .028"; could the plugs have been fouled from the hard-start non-buring initial startup I went through? Rifledriver (Brian Crall) our resident expert told me once before that it will take some driving for the ECU to relearn all the engine parameters back after battery shut down (as I did disconnect the battery during the install). Could it be that it will resolve itself after some more driving?

Jeff, Bill and others who may have this installed, I would appreciate your comments and experiences.

Overall, I think it is a great conversion, and someone should really think about putting this together in kit form.

Here's some photos.

Regards,

Alex
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I recently tried this setup on my countach. I had a similar experience also. Idle and midrange was fine, but 6k RPM and above had random misses. I've shelved it for now. I think the parallel wiring and wasted spark is not compatible with the MSD unit. This is a link to the MSD tech forum where i posted my problems.
http://www.msdignition.com/forums/invboard1_1_2/upload/index.php?act=ST&f=2&t=4620&hl=denso&

and here is thread with another possibility
http://www.efi101.com/forum/viewtopic.php?t=390&postdays=0&postorder=asc&start=60

I'm going to try dual AEM units and have 1 driver per coil. this may work better.
any body want my DIS-4 units? $200 each.
Dennis

 

Alex, until the experts arrive, I will throw out that it's pretty important for most cars to learn idle after the battery is disconnected. The car should be started and left to idle. NO revving, just let it idle. You may want to disconnect the battery again and have another go of it.

Of course, this is just a guess and may be complete B.S. but costs nothing to try.

Good luck,
John

 

Hi John,

Thanks for the response, but yes, I did let the car idle for at least 20 minutes. I then shut down the motor, rechecked everything, and then went out for the drive. Sorry, I left that part out. The car idles fine, revs to redline, just some roughness at part throttle and cruising speeds.

regards,

Alex

 

my countach has been upgraded with a motec EFI and it is distributorless. An ignition expander is used to drive 6 coils in a wasted spark config. Functionally, this is equivalent to the bosh system, but with 4 extra cylinders. I've been thinking about this mod for a long time and have heard of others doing COP conversions (but not with wasted spark).

 

Hi All,

I hope everybody had a great turkey day.

I had a chance to take the 355 out for a spirited drive yesterday, and put around 130 miles on the car. I was hoping that the issues I have been having about 2 posts ago would go away, via ECU remapping and relearning. No such luck.

As a matter of fact, it kinda became worse during the day. It was stumbling pretty badly between 3500 to 5000 rpms in part throttle, cruising speeds, and if I let this condition go on for several minutes, the "Slow Down" light blinks. I let off the gas and take the revs out of that range and the light goes off. This happened twice.

Then accelerating to redline produced a pretty consistent hiccup at around 7000 rpms. Anyway, I came home a bit frustrated.

I have been working on the car since then, and here's what I've done thus far:

1. First, I was frustrated enough to decide to take the system off line (without uninstalling it, until I'm sure the bugs cannot be fixed) and reinstalling the OEM coils and cables and spark plugs just to get the car running the way it was. Then I discovered the source of my original misfire (the whole reason for this conversion), a broken spark plug boot, allowing arcing at cylinder #8. Shoot. After talking with my good friend who happens to be the service manager at the local Acura dealership, he says not to give up just yet on the set up as it is superior to what the car originally came with. Fine.

2. So I put back the system, rechecked everything, tried a different wasted spark setting on the DIS, no change.

3. Regapped the spark plugs, tried .025, .028, and finally .031, no change. Well, maybe the idle is a bit rougher with the larger gaps. But the hesitation is still there.

4. Rechecked the wiring, and this time I used a continuity tester. Remember I got this kit from Billwann, and I assumed everything was in order. Discovered that the COP wires at cylinder #4 was reversed. May or may not be a big deal, but I still corrected it anyway. Everything else OK. No change.

5. Adjusted the length of the COP wires to Cyl #8, as it was too short to begin with, necessitating the COP at cyl #7 to be mounted with the connector facing #8 (vs. having all the connectors facing the same direction). I thought the connectors and the wires were too close to each other and there might be some cross talk there. No change.

Here are my thoughts. I have 2 tach adapters (Dual ignition adapter PN 8912) wired into the harness, as I received it from Bill. Should I try to run it with the adapters disconnected?

Do I have bad COPs? Bad plugs, perhaps? How do I troubleshoot a defective COP and/or plug? Or even a bad DIS-4? I have done some reading online, and it seems that there was a problem with stumbling and misfiring with the newer DIS-4 PLUS, while there were no issues with the original unit (that Jeff has). MSD techs has also mentioned several times in their forums that we cannot run dual coils in parallel from one output.

So now, I am stuck. I have a kit that does not work properly, and have tried everything I can think of and made sure it is by the book. I can't even go back to OEM right now as my cables are shot (how much were those again?)

Oh, as if to add insult to injury, I passed by the F-car dealership yesterday, to pick up a set of spark plugs, in anticipation of going back to OEM as I had originally thought my original plugs were fouled. Anyway, I was told by the parts manager that they have the "latest and greatest" version of plugs for the 355, but these plugs were the most expensive ones he has ever seen. Errr.. OK. $43... apiece. And that's with my discount. You mean these plugs are more expensive than that of the Enzo's? Thinking that it might be better than what was on the car originally, I bought them. Only to find out that these plugs were exactly the same as what I had on the car (NGK PMR7A). Sigh.

I shouldn't incur any damage to the ECU or motor while going through this, right?

Any tips as to where to proceed from here are appreciated.

Regards,

Alex

 

Thanks, Jeff, for the reply. I will try your suggestions and will report back. Yes, it will be a shame if I cannot get this to work and abandon it at this time. Except for the hesitations, the car really feels stronger and I like the smooth idle. Makes standing starts with the F1 tranny very smooth.

I also posted something at the MSD tech forum, we'll see what they say.

Alex

 

gee, all this hassle and a set of genuine leads for $1200 is starting to look pretty good value eh?

Just think of all the bore washing and cat contamination that's happening during an ignition misfire

ugh!

Oh well, as long as it's all documented, we can all benefit from the misfortune and failed ideas of others.

Good on ya for trying, but I'd give it up as bad job.

 

AVMotorsport-I saw your followup question on the msd forum. I wouldn't hold my breath for a coherant detailed answer from msd tech support. I believe they are fire fighters more than experts. FWIW, I did call before purchasing the DIS4 and described in detail what i intended to do, but said it was a v-6 wasted spark config, as i didn't want to mention lamborghini. People give skewed answers when exotic names are mentioned. They said absolutely no problem, this will work using the denso coils. I then bench tested the setup before installation using a pulse generator (I had the older dis4 with dip switches, msd claims they are identical to the new ones though). Needless to say, I was bummed when it didn't work after installation. I put alot of time into it fab-ing various parts. I think the MSD is not suited somehow driving the denso coils. I'm going to try again in the future, but use motec or M&W. the only other thing you might try is a smaller plug gap. 0.020".

 

Hi Dennis,

Here's what the MSD had to say on this: " A DIS 4 will run a coil per cylinder setup but with only half of the output getting to each coil. Basically, you're splitting the 480 volts from each output to the two coils. This may show up as a misfire or a lack or high RPM performance. "

Somehow I don't buy this reasoning as the COPs are wired in parallel, and should not have a voltage drop, unless the DIS-4 can't just handle the additional load (ie. amperage) and would overload. And what I don't understand is why at least a couple of people on this thread (Jeff and Bill) has had resounding successes with their setups, and my setup is exactly like Bill's.

I will be trying one more thing before throwing in the towel.

Oh, and spending that $1200 on a set of OEM spark plug cables still doesn't sound too good, not yet anyway. Heck, it is not really the money, after all, I just spent $400 on a set of spark plugs.

Anyway, thanks for all the input.

Regards,

Alex

 

they are correct in saying the energy stored in the capacitors will be split between the 2 coils in a wasted spark setup. Iin parallel configuration, the voltage is the same, but the current is split between then. In a serial config, the voltage is split, and the current is the same. Either way, the energy is split evenly between the cylinders. I perceived a slight advantage in the serial config for a v12 application. IF one coil went bad, then 2 cylinders would drop. This would be obvious when it occured. In contrast, the parallel config would only drop 1 cylinder if 1 coil went bad. This may not be perceptable since a v12 is such smooth runner. Anyway, I tried both serial and parallel, same result. I too am glad a few guys on this thread had success with it. I try again in due time. $1200 for wires...sheesh.

 

I am a little baffled as to why the DIS-4 would not agree with the Denso COPs. I wish I had the 348 back so I could get working on this was well to see what happens with my car here so we can at least have two confirms or "this doesnt work" cases.

All I can think of in the case this isnt working is that one of the COPs is bad or something is wired wrong or has come un done. I can't see how the DIS-4 would cause a problem with misfiring in the 3-5k range unless for some reason the transition to a single spark is funky or being hosed by the DIS-4 box itself.

 

the only thing i can think of...maybe crosstalk between the signals. twisted pair wiring could have helped if this was the case. It just makes no sense that you guys got it to work. Another thing, maybe a smaller gap. I tried 0.030" & 0.040".

 

Hmmm, I don't know. I have tried to approach this in the most scientific way possible, checking everything and trying to make one change one at a time, then logging the results. No improvement in every case. I also spoke with Bill yesterday about it and he says that the COPs were good as he tested the resistance of each of them, and they were well within spec of each other. He also ran the whole setup on his car, which ran well, before taking them off and sending them off to me. The only thing I cannot confirm is the harness itself, as I did not build them myself.

He did make a good suggestion, to try and get the best ground spot possible. So my next task is to run a beefy wire from the negative terminal of the battery to the engine compartment, to make sure I get a solid ground. It is known that these cars have a grounding system that is iffy at best, and at the same time the DIS box seems to be very sensitive to the quality of the ground connection.

It has been a really interesting learning experience for me. I love working on car like these as a hobby, and this is probably the best way to learn more about them. The car is really fascinating, but the more I learn about it, the more I am baffled as to why it costs so damn expensive to fix these cars, and why (a big WHY) they charge so much for parts.

Thanks for everyone's interest, I'll keep in touch.

Alex

 

i bet TP wiring was the critical factor here. interesting.