im MartinB

So I had a customer call me from the Dyno a couple months ago. Guy was telling him he was losing a little HP over 5200 RPM and said it was the dist to blame, something about the timing getting erratic right around the 5200 rpm mark and sure enough you could see the numbers dip. Engines are 572 NA motors. Switched out to MSD systems and supposedly gained about 20HP a side. I'm curious to know if anyone else has had this similar experience? I know the dyno guy wasn't just trying to sell him parts so lets just assume he wasn't. I called a couple vendors and of course no one has ever had any issues with any of their products not being the best. I'm mainly just wanting to find a new option so this doesn't happen again... Initially I did some research and we even lake tested a couple different options and we never noticed any difference between the cheaper dist set ups and the perk ignitor IIs. "Run Ready" Max Volt Ignition Package is an option I am considering going forward... Wondering if anyone has any insights...

articfriends

Once they were warm, engine would sorta flat line between 4800 and 5200 vs pulling to top, if you held a timing gun on it, the timing seemed to be erratic and not hold "steady" as in wandering, the power loss was worse than 20 hp "warm", I dropped in a used shop MSD that was in my cabinet after swapping caps , coils and distributors between both engines and pulling it on dyno over and over again and it immediately pulled correctly. Did you notice how sloppy the pick up coil was in those and how it can move around radially and side to side? I blame the slop in screwing with the air gap between the reluctor and pickup, msd's arent necessarily great but did work correctly. Your customer also mentioned hes had something in them fail in the past out on water but that was unclear, Smitty

articfriends

Thinking back on this too, one distributor carried higher by about 400 rpms then other one before acting up but neither one carried to top like the MSD did, at a certain point I was questioning the valve spring rate or standard wall pushrods flexing as I have never seen TWO distributors from a pair of engines both have issues and I was really starting to get convinced it was spring surge or valve float. Later on too though once I did get ignition to pull to top and I actually started tuning it I also found the power valve in secondary broken off and wedged partly open/closed from someone who previous worked on it. Then of course as you remember i found it reverting oil back into the cylinder 5 at idle (another new one to me) from # 5 exhaust valve guide being wiped out. . What did your machine shop end up telling you on that one when you asked them about it? It was a challenging dyno job for sure!

articfriends

Heres a few other pics I still had on my phone from this dyno session. I also found the distributor gears quite scalloped on the pertronix distributors when I was chasing all these gremlins. These issues DO highlight /re-enforce why everything performance should be dynoed.

articfriends

Here's a video of the pickup slopping around , there's no fasteners to be tightened, it sorta locks on a piece of plastic that was womped out.

articfriends

Here's another video where you can see how loose the pickup is and how it randomly can move around, disappointing that there's no fasteners, just cheap.plastic holding it together. You can see the reluctor turning the trigger light on and off in the first video, this would equate to timing jumping around randomly which is what I saw running

AmiableDave

Nothing to like about the two videos. But I gave it the thumbs up for showing the problem.

TomZ

I’d use a MSD ready to run in a second. Good distributors so long as the advance mechanism is tended to for corrosion.

Ignition boxes… that’s another thing.

larose481

I'm guessing you could find a tighter setup in a brothel! It's also spelled Pertronix not Perkotronic. Setting the competency aside because of spelling, I wouldn't use any of there stuff as I've installed a handful of there point conversions and all have failed. I would take points ignition over this crap. So I look at it this way, dyno guy found the problem and corrected it and was able to tune it, correct? I'm assuming you got your junk stuff back as its labeled at no value so at this point, why don't you verify total timing set on the dyno and pull the MSD distributors out and drop either or both PERTRONIX (spelled correctly) distributors in and see how they perform at the same peak RPM?

BadDog

Hmmm, a complete Dist and Cap for about the price of a Cap n Rotor. I would expect they are cutting corners somewhere.
https://swperformanceparts.com/produ...e-installation