articfriends

So the OP is guy who built the 2 572s or probably more correctly had swapped lifers and cams, re-gasketed some stuff, wasnt necessarily a "fresh" FULL build.
The owner of the (2) 572's contacted me on dynoing both. Once on dyno engine one once I heated cycled it, did my ring seating/break in sequence,checked lash on rockers etc would never pull to top twice the same. On first hard pull it seemed ok but went flat after 5200/5400 and was no where near the expected power, timing was checked multiple times. As it progressed it seemed to flat line even earlier starting at 4800. Timing was real jumpy and erratic. At that point I was only observing AFRS on tailpipes because until I have one close to dialed in, I do NOT put the 8 o2s in as a real rich condition or motor pumping oil (as it turned out this one was) kills the sensors. so I swapped 2nd coil from engine 2 on, made no difference. Swapped distributor from engine 2 in, rpms it went flat at seemed to go back up to 5400 but still not right at all. Started suspecting valve float/valve train instability. Found all that slop in the pickup coil assembly of the pertronix and no way to tighten it up so I swapped in a shop msd, pulled right to 6000 fine. Spoke to customer who said yes, get different distributors AND ALSO TOLD ME AT THAT TIME BOAT HAD BEEN FLAT LINING AROUND 5200 FOR LAST COUPLE YEARS regardless of props and he had blamed the safety tether switches. When I pulled the Pertonix distributors I also seen the gears were worn which was puzzling as owner had told me these were fresh builds but later told me most these parts had 80 something hours on them. The owner was also concerned with hot idle oil pressure and it wasnt real great on dyno at 150/170 degrees, told him was most likely gonna be worse in boat when its 220 although he could adjust the weight.
At this point I wanted to start actually dialing in the tune, afrs were off (lean), pulled customers carb apart and found rear power valve broken off and wedged, I was told before engines were dropped off they were fresh (the carbs) then was later told it had been a while.. I went thru carbs with all new gaskets, power valves etc started dialing in tune. At that point it had also been smoking on 1/3/5/7 side and I had changed plugs at least once. I was still observing alot of exhaust smoke so pulled plugs again, #5 was about oil fouled, scoped intake runner on 5 to see if it was sucking oil from intake gasket, port was dry. At this point pulled exhaust, there was oil dribbling out port on 5, informed owner any further dynoing would be a waste of time until oil source was determined and fixed. Engine came off dyno, went back for to OP for repair. Expected to see it back to finish dynoing but they elected to put it in boat and just have me calibrate carb for it same as what engine 2 liked when I dynoed IT.

compedgemarine

I have 7 or 8 of the chinesium HEI distributors here at the shop, how many do you want? all of them came in customers cars and only lasted at the most 250 miles. most failed within a week or 100 miles or less. they are nice and shiny tho so they have that going for them.

im MartinB

Update: Solved an issue on a different boat with similar issues IE loss of about 4 mph top speed on a pair of 540s. We swapped out the "Pertronix" to MSD and boat ran its fastest speed to date. So now it's 2 separate instances inside of a year where these units were costing significant power loss. I'm sure a lot of applications wouldn't notice but in a boat it directly affects the top speed. Therefore I feel fine saying these do not belong in a marine environment at all. I called "Pertronix" and talked to a tech and he said he had never heard of this issue and should send them in for testing. I sent in the email he requested and the response was they no longer do any testing. It's surprising for these units to have such a following in spite of this obvious issue.

articfriends

Did you see in the video I made of your bad distributor how I can wiggle the pickup enough to turn the signal light on and off? I always thought pertronix was quality stuff until I saw these weird issues on your customers distributors

Rookie

I used the Pertronix Ignitor in my old Sea Ray with a 351 Windsor to eliminate the points. Boat ran great with the conversion. But after a while I loss power, then gained power, then loss power then gained power. Was real inconsistent. Maybe it was this unit... I've always been baffled by this. One day it would run great then the next it would not get on plane.

larose481

Like I mentioned before, I've installed a handful of points conversions on stuff that aftermarket distributors aren't available for only to have them fail. Pertronix has warrantied them only to fail again and I ended up going back to points as they are a fail safe set up given adjusted properly. Articfriends, I watched the video and can only imagine how the timing bounced all over in actual running condition. Likely a few more degrees in both directions than you get by hand. Good catch! There is a reason you are one of the most sought after tuners cause you find everything!