capacitor on +12v wire for ls cop wiring

[turbo6man]

I am going to wire in capacitors for my LS2 coils as per here: http://www.msextra.com/doc/ms3/ls1.html . I know they call for 1.0 uf Capacitors. My question is what type of capacitors do I want to use, ceramic, paper etc.? Do I need one per coil, one per bank of four, or one for all eight? Can I wire them halfway from the ms3 ecm to the cop (this would cleanly put them on a board under the dash) or do they have to be out in the engine compartment at the cop
Thanks

[myk777]

Mylar/Film caps, I used one per bank on my v8 close to the coils.

Mike

[aarc240]

Use ceramic capacitors, placed as close to the coil as possible.
If anyone is already using mylar film caps in the engine bay, plan on replacing them regularly or switching to ceramic capacitors.
Mylar film capacitors have a rated life of 1,000 hours at 105 degrees, 30,000 hours at 40 degrees (both Celsius) and the characteristic curve is nothing like linear.
By 50 degrees the rated life shortens by nearly 40%.
As the engine bay can easily reach 65 degrees on a cool day and much more on a summer stinker, mylar film caps don't have a good life expectancy.

Hopefully, this might save someone some head scratching down the line

[SymTech Laboratories]

Ceramic capacitors are certainly the best choice for this application. Be sure you select capacitors with an appropriate voltage rating (at least 22V for 12V automotive systems).

Bypass capacitors, such as these, work best when physically located as close to the device as possible. Ideally, you should install one per coil.

[Peter Florance]

Overkill, but I use Ford EDIS capacitors.
Easy mounting too.

[preston]

What are the potential problems with not using the capacitors ?

[myk777]

Use ceramic capacitors, placed as close to the coil as possible.
If anyone is already using mylar film caps in the engine bay, plan on replacing them regularly or switching to ceramic capacitors.
Mylar film capacitors have a rated life of 1,000 hours at 105 degrees, 30,000 hours at 40 degrees (both Celsius) and the characteristic curve is nothing like linear.
By 50 degrees the rated life shortens by nearly 40%.
As the engine bay can easily reach 65 degrees on a cool day and much more on a summer stinker, mylar film caps don't have a good life expectancy.

Hopefully, this might save someone some head scratching down the line

Here's the one's I used, they show an operating range up to 185deg F, seemed plenty for the wiring harness in my application. There's no life expectancy data, but I assumed if you stayed within the mfg operating temperature range they would have a very long life?

http://www.nteinc.com/capacitor_web/pdf/mlr.pdf

Mike

[turbo6man]

Thank you everyone for the help.

[Ollie8974]

Overkill, but I use Ford EDIS capacitors.
Easy mounting too.

Can you post a part number?
Thanks

[Peter Florance]

Overkill, but I use Ford EDIS capacitors.
Easy mounting too.

Can you post a part number?
Thanks

It says F6AF-18801-AA on it

I think that is a Ford #

[Ollie8974]

Thanks, Peter

[aarc240]

@Mike
Right there in the data sheet "Life Test: 1000Hrs @ +85°C (+185°F) at 150% rated voltage"
Not pushing them to their voltage limits will certainly extend the life but all the test data I've seen indicates by no more than x2.

I'll second those thanks Peter.

[myk777]

@Mike
Right there in the data sheet "Life Test: 1000Hrs @ +85°C (+185°F) at 150% rated voltage"
Not pushing them to their voltage limits will certainly extend the life but all the test data I've seen indicates by no more than x2.

I'll second those thanks Peter.

You must have missed this post:

viewtopic.php?f=132&t=43528#p307625

From what I found its more like a factor of 157x....157,000hrs is plenty for me.

Mike

[Peter Florance]

Here's a photo of the cap mounted on LS2 coil

edis_cap_ls2_coil.jpg (58.61 KiB) Viewed 901 times

wow, I needed to clean my bench that day...

[Peter Florance]

Also Mazda N3A1-66-991 (RX8) is similar.

[turbo6man]

Thanks I went to my local wrecking yard and they have a bunch of them and they sold them to me for $3.99 a piece. I bought 4 and I think I will set it up with one per two coils and see how that works. If I have issues I will buy 4 more and put one on every coil. Just to be clear I will not hurt anything in the ecm, It may have a noise issue causing a sync or a misfire condition right?

[Peter Florance]

Thanks I went to my local wrecking yard and they have a bunch of them and they sold them to me for $3.99 a piece. I bought 4 and I think I will set it up with one per two coils and see how that works. If I have issues I will buy 4 more and put one on every coil. Just to be clear I will not hurt anything in the ecm, It may have a noise issue causing a sync or a misfire condition right?

I think there is no downside to using them.
2 per coil seems like plenty

[MadDart]

Overkill, but I use Ford EDIS capacitors.
Easy mounting too.

Can you post a part number?
Thanks

It says F6AF-18801-AA on it

I think that is a Ford #

Where are you buying these at?? So you are saying that 1 per bank of 4 Coils is fine? Looks like there are 3 wires on these Capacitors. What wires go where? Looks like a ground, hot in and out of the Cap?

[Peter Florance]

Where are you buying these at?? So you are saying that 1 per bank of 4 Coils is fine? Looks like there are 3 wires on these Capacitors. What wires go where? Looks like a ground, hot in and out of the Cap?

I'm using junkyard parts as I can't find the correct part #.

Single wire that attached to 12 volt line. The mounting bracket is the ground

[turbo6man]

I went to my local "Pick and Pull" wrecking yard and just started looking at the newer ford cars and I found an abundance of these and they had the same p# as Peter posted.