F355 coil-on-plug conversion

The stickers on my car are the same as the molded numbers (at least on the right side). Whether the spark plug leads go to the corresponding cylinders, I haven't checked.

 

member: 114"]The F355 already uses wasted spark system. There are two stock ignition coil paks, that each pak gets its signal from the stock ECU, and each coil pak each has four high tension lead outs that then goes to each individual plug. The MSD DIS4 takes the original signal from the stock ECU that went to those stock coil paks as it's inputs, the stock coil paks are not used and discarded. The MSD DIS4 amplifies and multi-sparks the low tension signal from the ECU out which then goes to each corresponding cylinder numbers coil on plug. The MSD DIS4 is NOT an ECU, it is a glorified dumb spark amplifier that sends its signal to the repositioned Coils that sit On the Plug. Has nothing to do with engine timing as the stock ECU still maintains that function.. One can use two DIS4 boxes (at twice the cost) or a DIS8 (don't think they make one), but that would be redundant and not really necessary.[/QUOTE]
The only advantage that I can see for using (2) DIS 4 channel units, or a DIS 8 channel unit if they make one, would be to not weaken the strength of the signal leaving the DIS (Ditributorless Ignition System ). A 4 channel box will have to fire twice as many coils during the same time interval. Does this dahminish it's effectiveness or shorten it's life? I don't know but common sense says that it would. BTW, there would still be a wasted spark but not for 2 cylinders.
With that said (and I am just "spit balling" here). My same question of dehminish strength would now apply to the signal from the ECU to 2 DIS boxes in stead of one.
Now, if DIS 8s are available (haven't seen any but I don't know why because there are a lot of non-flat plane V8s out there that could use them, that might be a good path to take.
PS firing 2 cylinders at the same time as Ferrari does here is only possible with a flat plane crank. "Standard" cranks with other offsets besides 180 degrees can't use a wasted spark system.
Most US cars were not built with flat plane cranks but some of the latest, high end, Ford (Shelby) Mustangs have been using them.

 

The only advantage that I can see for using (2) DIS 4 channel units, or a DIS 8 channel unit if they make one, would be to not weaken the strength of the signal leaving the DIS (Ditributorless Ignition System ). A 4 channel box will have to fire twice as many coils during the same time interval. Does this dahminish it's effectiveness or shorten it's life? I don't know but common sense says that it would. BTW, there would still be a wasted spark but not for 2 cylinders.
With that said (and I am just "spit balling" here). My same question of dehminish strength would now apply to the signal from the ECU to 2 DIS boxes in stead of one.
Now, if DIS 8s are available (haven't seen any but I don't know why because there are a lot of non-flat plane V8s out there that could use them, that might be a good path to take.
PS firing 2 cylinders at the same time as Ferrari does here is only possible with a flat plane crank. "Standard" cranks with other offsets besides 180 degrees can't use a wasted spark system.
Most US cars were not built with flat plane cranks but some of the latest, high end, Ford (Shelby) Mustangs have been using them.[/QUOTE]
For those of you interested, here's a photo of my current coil arrangement with 8 coils arranged across the back of the engine. Going to leave it this way for the time being.
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I'm trying to follow what you're saying here. Are you saying two cylinders are being fired at the same time, but one is a wasted spark? Ferrari 5.2 Bosch coilpacks are used on Range Rovers and Protons. Surely these cars don't have flat plane cranks?

There are only two coil pairs in each coil pack. On the right hand bank, cylinders 1 and 4 are fired at the same time, as are 2 and 3.

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Here's a random photo from the internet of a F355 coilpack...

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I don't understand what you're saying about the numbers not lining up.

 

First, a disclaimer. I am not an authority but simply an elderly, gear head, engineer who is becoming familiar with this coil pac/flat plane crank/wasted spark issue.
There have been two different senarios presented.
1.) The stock Ferrari 355 (2) coil pac arrangement. Each of the 2 pacs has 4 outlets (1 for each cylinder/spark plug).
Now, why a wasted spark system?
Not knowing any better I suspect that a control has difficulty determining a firing point when the trigger on the crank wheel comes around to be detected every 180 rather than the required 270 needed in a four cycle engine. I can imagine that the ECU could be set up to count every other trigger but each new time you start your engine it may not be able to distinguish which trigger is at the top of the compression stroke and which is at the exhaust stroke SO, just fire at them both and you can't go wrong.
2.) Jeff, and perhaps others, are tossing the 2 stock, 4 outlet, coil pacs and installing one MSD DIS4 amplifier and 8 "coil-on-plug" coils. (They could use 2 MSD units with one channel per coil but for the expense). It's not clear to me exactly how but it seems that they split each of the 4 outlets to cover the full 8 cylinders. Now, because the stock 355 Bosch ECU (either version ) is already set up for "wasted spark" (double firing) the split outputs can be arranged to fire the cylinders like 1 and 4 that are at TDC at the same time but on different cycles (one will be the wasted spark).
This is how I see it anyhow. Be glad to learn though.

 

I want to correct what I said above. The firing trigger on the crank comes around every 360 degrees (not 180) but the 4 cycle engine actually fires every 720 degrees. So, does a control system, Bosch Motronic 2.7, 5.2 or any other, have difficulty determining which revolution of the crank is actually the correct firing point? You can solve this dilemma by simply firing every revolution thus creating a "wasted" spark. Note: The 355 has a cam position sensor that should take care of this dilemma because the cam rotates at half the speed of the crank.

 

So the wasted spark system on the 355 is wasted?

The 355 setup may be just for convenience. Bosch off-the-shelf components. Only one coil required for two spark plugs.

 

A little more. late breaking info;
I spoke with a Nissan sponsored professional Drift Team and they use the CoP coils from a Nissan GTR (they contain ignitors and therefore an MSD DIS4 Box is not needed). The have more than one car and for one of them they produce their own, custom, noses for a shorter unit.

 

Any progress reports from. Anyone's conversion efforts. I haven't done any more because I don't feel confident enough in my understanding of the whole issue. I don't have either Bosch ECU. My system was adapted by PROEFI out of Phoenix before I got the car. There was a reason for that that I don't need to go into here suffice it to say that it was deemed necessary. Anyway, would like to hear any new developments and long term experiences.

 

My engine number is 3309562. What does that tell me about the year/configuration of my car?
Thanks

 

Just reading a few of the more recent posts.

For a 90 degree V8 the difference between flat crank and a cross plane crank with regards to wasted spark is that on a flat crank the cylinder at TDC on compression and the cylinder at TDC on exhaust are on the same bank. With a cross plane crank they are on different banks. On any 90 degree V8 you always have 1 at TDC compression, 1 at BDC of the power strike, 1 at TDC exhaust and 1 at BDC of intake. The other 4 cylinders are 1/2 way up or down the bore on the same strokes. Again, the difference between flat and cross plane is what cylinders on which bank are at what position on which stroke.

 

Strange... According to the parts manual, engine numbers have 5 digits. My warranty book also shows 5 digits.

 

Maybe I've got the wrong number. This 7 digit number is what is stamped on the flat surface just forward and to the right of the oil filter in the valley. Should I be looking somewhere else

 

You've got the right location, but on my engine (just checked), it's 5 digits.

Curiouser and curiouser

 

Do you have the stars on your engine number stamping?

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Just wondering if Challenge cars and Fioranos have 5 digits.

 

On closer inspection it looks like an original ID may have been ground off. I can see the remains of a star in the lower right corner. I will try to get a photo.

 

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Seems like this engine "fell off the back of a truck" Someone has gone to extraordinary effort to conceal the identity of this engine. Are there any state legislations which might prevent you registering your car with an old engine number?

I tried to use a graphics editor to see if I could pick up any detail from the photo, but no luck.

I don't think you could even say the last 5 digits of that 3309562 number show the engine number. I don't know if F355 engine numbers are sequential, but my '98 car engine number is 50071 (around 11,000 F355's were made). Perhaps you could ask the folks on the 355 forum if their 2.7 cars have any engine numbers which start with zero?

(EDIT: Looking at parts manuals, 2.7 engine numbers may start with 38xxx)

 

This car (engine) was sourced from the UK and I have inquired for more information. Maybe we'll get some explanation of the Plug cover and engine ID mods.

 

Just found this thread and it is intriguing and seductive...sounds like a great mod.....

Have there been any upgrades for this set up since the original 2004 post? With 18 years of advancements in technology I would "assume" that there might be something better than the MSD DIS4? Or perhaps the MSD DIS4 continues to be the gold standard?

Anyone have more info on these coils? Truly no need for DIS4 box?

Is there consensus on which CoPs fits best? Is there a Goldilocks version that will fit under the wire cover? No problem with making a spacer, but I also like the idea of using stand offs and letting some air in around the plugs, or is that pointless?

 

I won't be much help to you because I still haven't done this mod and have had other issues to deal with (Bosch-005 Throttle Position sensor acting irratic to the point that the dyno guy wouldn't work with it. Got new TPSs from Estonia and Latvia and tested the car this morning - all seems well and I can move on to other issues soon).
I am pretty good mechanically (mounted my plug cover plate on standoffs to promote better cooling and provide greater plug wire separation - both of which would be helped by a CoP system) but way over my head electronically (wasn't good with points and condenser much less HEI) but COIL on Plug sounds like a good move to me.
Anyway, I am still interested and will follow this issue closely. I was thinking it best to make new plug cover plates that would allow for longer Coils to sit outside the plate while being secured to the plate. I realize that this would negate the stock Ferrari cast plates and that I might not want to do that but it would put the coil out in the air and not trapped under the plate. More to think about.
Let me know how you progress.

 

I envy you your ambition to get your engine converted to CoP and you are absolutely correct about the importance of the cover, the gaskets and grommet or else the engineers wouldn't have gone to the trouble.
I was recommending a completely new cover plate utilizing the stock seals and machined to accept the two each coil mounting screws where the coils themselves sit on the plate
with the nose long enough to connect with the spark plugs. My current individual standoff bushings work well for my driving habits (to and from Cars and Coffee gatherings in fair weather) but it is probably not appropriate for standard car operation (remember that mine is a replica racing car project in use once monthly)
Still interested in all CoP developments now that my Throttle Position sensor issue is behind me.
PS - somewhat surprised that you untilized used, and unknown, motorcycle coils after invested so much time and effort on the project.