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Seems like alotof pressure on a 5/16 pushrod. Wonder if its deflecting and pole vaulting? Cant get a 3/8 in there?or a tapered version
 

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Discussion Starter #23
Unfortunately no I can’t. But these are the largest wall thickness 5/16” pushrods available and aren’t showing any signs of deflection on them yet. Manufacturers in a couple brands all agreed that where I’m at for pressure should still work fine and the first signs would be pushrod problems/failures? Our camshaft profile is also extremely smooth and doesn’t run nearly as much lift as what most guys are this level would be, so that could explain why it hasn’t had any issues there yet?
 

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A pushrod can do some flexing and not break for a while. That is a little pushrod, but if your cam profile is mild and small, it may not be a big deal. Are the springs set up fairly close to bind? If not, they could be surging. Usually that just breaks the spring though.
My first thought would be ignition related something is the problem. I had one stupid wire that was just a little loose cause me heartburn my first season on efi. That can be such a nightmare. Found it finally though.
 

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Discussion Starter #25
We were .136” away last season and this season .086” from coil bind which should be closer to optimal. I was always told that deflection and harmonics kills valvespring life? My current springs have 3 seasons and likely 200 passes and still test as good as the day they were put in? I test them on the bench frequently.... I would also think deflection would show some signs in the side of the pushrod / guideplate wear? Everything looks mint there too...
 

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Deflected or denied every possible solution, what was the reason for the thread?
Must be bouncing off the top rev limiter. 🤔
 

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Discussion Starter #28
Well, like the original post started out asking, what are the signs of smart coils not getting the job done? Are they killing coils? Are they melting wiring? I’m just going over the basics with both wiring and mechanical components on the car. I guess the easiest solution would be to just buy the MSD system for the car and see if the problem I’m having goes away? But before I do that, I’ll be trying the larger dwell setting, tighter plug gaps and raised spring pressures that were brought up in this discussion. Given the situation (Virus crap) I haven’t had a chance to test any of those things Yet. I will report back before changing anything ignition wise. And ironically enough, I Actually had suspicions of the main rev limit coming on early, and plan on raising it a bit to rule that out as well.
 

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We run .012" gap on ign 1a haltech coils, 7ms dwell above 5000 rpm. Msd wires, 60 psi on m1, 12 gauge wire going to each bank i believe. Holley engineer told me a 1a coil will pull 5a at 5ms dwell at 8500 rpm. We have no ignition issues. Burns the same gpm of fuel the mag did..
 

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Discussion Starter #31
Sure sounds like .012” gap is a good place for me to start, as well as 7ms down track. Thanks for your input.
 

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Discussion Starter #34
if the timing isn’t sequential on a coil near plug deal it won’t run. The only other thing is if you were asking if we use individual cylinder timing control? ... we run a couple cylinders with less timing in them?
 

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Nick, for what its worth there is a local racer in NC that I know personally that has been qicker/faster than anyone would believe could be done on a MSD 7531, turbocharged on methanol. 186 or 189mph the best I remember and did it with .011" plug gap. It has also been discussed on YB the fact that not all EFI systems fire the coils the same and some are simply better than others. A few years back I remember Carl Stevens Jr went 221mph on smart coils and Motec EFI on a hemi. Just food for thought.
 

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Discussion Starter #38
Yeah I have heard about different efi systems and their abilities to fire the smart coils. That’s a whole other topic that I’m sure guys can get heated about. Fact remains I need to test this thing with a tighter spark plug gap than the .016” I had been running, as well as run the coil packs with a true 7-8ms dwell. The only other thing I had questions about is if smart coils can wear out? These have a fair amount of runs on them, at high boost. Likely 140-150 eighth mile hits?. All of this is theoretical til I test things out. I will report back once the track opens for testing.
 

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Someone at FuelTech told me that you can run the dwell as high as 8ms when using sequential timing on methanol, not on waste spark.
Any dwell depends on time between cycles....ie rpm. Let's see anyone try and run 8ms at 10,000 rpm. 1,000 rpm...plenty of time.

( Obviously wasted spark...ie 2 sparks per 720 cycle offers 1/2 the time available of 1 spark per 720 cycle )

Of course you could debate if over saturating the coil offers any real benefit too ?
 

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I would say no on the "wearing out" aspect of the conversation. The smart coils use basically the same technology that has run AC VFD motor drives for over twenty years. It is a gated SCR that is 100% solid state. Power is pulsed on the gate which in turn allows the semi conductor to pass current until the ECU deenergizes the power to the gate stopping the current flow.
 
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