Matts440
Well-Known Member
But if it was the driving electronics then even the good spark ones would have been weak, so the signal is strong on all. Just cheaper coils came with the car.
67 twin turbo dart
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Matts440
Well-Known Member
True, thats why I was only looking at name brands, and both companies have been around a long time.
Hemirunner
Well-Known Member
Holley does not
TT5.9mag
Two atmospheres are better than one
You are correct my apologies, Holley does not have individual output testing.
As for coil dwell, go with what the coil manufacturer recommends, not what MegaSquirt recommends. I used an aftermarket coil on our Jeep. Bench testing the coil, I got optimal spark at around 2.1 ms dwell (way less than your 3.5 ms). The Jeep ECU outputs a stock 2.8 ms. The additional dwell overheated the coil & fried it.
Hemirunner
Well-Known Member
Here’s the Holley smart coil recommendation. I set up a dwell table and I’m at 3.5ms for driving and gets to 5.0 only when racing.
Matts440
Well-Known Member
Thank you, yeah that's my current setting as well which from looking is also a good one for the Chevy type d585 coil, so don't think I burned them out just not the best quality ones I guess. I'll get the MSD ones ordered up here soon and just double check with them on their settings.
racerjoe
Well-Known Member
I would recommend this as well. This will help identify if there is a wiring problem for the individual coil, ie; poor ground, bad crimp, loose solder joint, etc.
IMO, stock D585 coil should be fine. Lots of guys making 800+HP with stock coils. Just my opinion, not everyone will like it...
Matts440
Well-Known Member
I can, but sending the signal without the spark plug and wire you can hear it clicking just no very little juice coming out. Both banks are grounded straight to battery and to the ms3 board. Those coils are probably factory one, thinking these are cheaper versions, even factory ones are up in price to $75-$90/per I've seen on some and AC delco brand name
I wouldn't do that without a plug sounds like the high voltage is flashing to the ground or the MS3 input wire could damage the MS3 poor insulation inside the coil even with a new unit the plug will limit the high voltage due to the smaller gap
Matts440
Well-Known Member
I sent my info on what's going on to diy or megasquirt and they said that the versafueler is not applicable since the ms3 can drive high impedance injectors and to remove it. The versa is for low impedance cause they pull so much juice they burn up. So that will be coming off as well and new coils.
racerjoe
Well-Known Member
You shouldn't hear coils clicking. That's likely the coil output finding a path to ground. When I did my initial test, I had the plugs removed and put a ground jumper to the body of the plug. That way I could see the strength of the spark. It was also neat to see how adjusting the dwell changed the spark intensity.
Matts440
Well-Known Member
Oh well I didn't know, still and always learning lol i just did yhe click test for a sec just to make sure the signal was going to the right one, just double checking my wiring. when I tested the coils with the plug and wire I used the same for each test so that way I can eliminate gap difference per plug, and the wires all ohm'd from 27-28.
New coils should sort out the problem went back & looked at the wiring all looks good also seems to run smooth enough in your shop wont be long now my i run my R3 up around 195 F seems to run a lot better once it gets above 180 have the same inlet manifold as yours mates going to LA next week to pick up some goodies & my strange DANA 60 4.1 ratio diff.
I have read this also, but more specifically factory d585 coils are good to 800+. As in junkyard finds. Reproduction 585’s can be hit or miss.
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TT5.9mag
Two atmospheres are better than one
Factory “good” coils are a non issue. I make about that power on stock gm coils. Hell Richard Holdener made 1530+ hp on stock coils. When tuned correctly (dwell time) and wired correctly they’ll be just fine.
^^Exactly
TT5.9mag
Two atmospheres are better than one
Matts440
Well-Known Member
I totally agree with the factory coils, don't think Louise went with factory being he was doing a budget build when he did this. I appreciate the offer, but he mounted the coils to the valve cover so the mounts for the d581 are different. I'll get some of the MSD ones coming here soon. I only had my dwell set to 3.5ms. Let me know about the d585 I can get the extra two that's no biggie. Thank you my friend.
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TT5.9mag
Two atmospheres are better than one
I’ll look tomorrow. I have 3, 8.1 vortecs and two of em have coils mounted one is a 01 the other is an 04, I think in 04 they changed to 581 coils from 580s. And I have a complete 6.0LS takeout that has some 585s on it. I remember some were missing. I’ll let you know.
Matts440
Well-Known Member
Maybe that was the start of the down fall of those coils, I never changed the dwell either just the injector size from that post. Everything else has been the same. It is odd.
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