Ya. Same thing just one picture is closer and at a different angle

Interestingly enough, as I was doing some research on engine break-in procedures, I found this article in the July-Sept 2017 edition of Engine Professional Magazine.

http://www.engineprofessional.com/ar...Q317_62-66.pdf

It mentions a two-year study about break-in of roller cams, although it gives no actual link the study itself. Also seems to be written by an oil company rep so read into that what you want. Interesting though. I'd like to find the study and read through its' findings.

 

Yea I see the dividing line now.

 

That is disturbing. Kind of like the engine block manufacturer forgetting a spark plug hole.

 

I found word-for-word an exact(?) copy of that here; https://golenengineservice.com/blog/...-in-procedure/

TBH, if I ever build another engine in my life that came with flat-tappet lifters, it's getting rollers

 

So I received the replacement lifter set. What do you know...No more ticking noise! I have driven now about 40 miles and believe I have a misfire on cylinder 4. I pulled the wire and had no change in exhaust tone or engine smoothness. I also have a very loud popping noise from the exhaust above 1500 rpms under load. I scoped Cylinder 4 with an in-cylinder pressure transducer and compared it to the waveform of a good cylinder(cyl 3) and they look identical. So, mechanically, cylinder 4 is sound. I have good spark also. I changed out the vacuum hose to the brake booster because it was cracked and it draws vacuum from the cylinder 4 runner but still misfires. I’m getting a ticking/squeaking noise intermittently from the cylinder as well. Just wondering if anyone has any ideas.

Engine Specs:

410 cubic inch FE
Factory 428 crank
Factory con rods
Silvolite pistons
Lunati roller cam, lifters, timing set
Trend custom pushrods
Proform adjustable roller rockers
Edelbrock performer heads with stainless valves
Edelbrock performer intake
MSD pro billet dizzy
MSD 8.5 wires
NGK spark plugs
Hedman headers
True dual exhaust with manga flow mufflers
Holley sniper efi

I have the sniper controlling timing advance. Initial timing is 6 degrees. Max advance is 35 degrees. Seems to misfire at all rpms. The popping from exhaust is basically there anytime you are past 1/10 throttle.

 

You have "good spark" on cylinder 4's wire?

 

Yes. It jumps a 30kv gap on my spark tester no problem. Nice Looking spark.

 

Have you tried another spark plug, sometimes it's just a simple thing that gets us..

 

I thought about it. I probably will today. I'm wondering if my timing needs advanced a little. If I remember correctly, I had the same ignition and fuel setup on my 360 and initial timing was set at about 15 degrees.

 

Here are the waveforms I collected to verify the condition of the cylinder mechanically:

This is cylinder 4. Looks pretty good. Has all four strokes and good compression for an engine with 40 miles on it





This waveform is Cylinder 3. A known good cylinder. I collected this waveform as a reference for comparison.






As you can see they are mostly identical. I will change out the spark plug this afternoon and see if the problem improves.

 

That looks good, hopefully it is something simple. The plug will be a cheap test at least. Over all the years I've been working on engines I have had only a few bad right out of the box, doesn't happen often but it does when you lease expect it. Even one drop on the floor can kill them LOL.

 

I now have about 80 miles on the truck and the noise has subsided. The engine seems to be running a lot smoother as well at least to 3000 rpms (I haven't gone over that threshold yet). I guess I'll just file that one under the engine break-in section. I did change the spark plug on Cyl 4 and adjusted the timing to 15 degrees so that could have played a part as well.

One additional question: I plan on using Royal Purple HPS oil in it after the break-in but am unsure of what weight to use. The break-in oil I'm using is 10W-30 and I have about 20 psi at warm idle. Should I move up to 10W-40 or just stay with 10W-30?

 

Oil questions will probably get you many different replies and opinions. My modified 390 idles at about 25 but builds to 60 quickly as rpm increases and never has been an issue, I'm using 10-30 and prefer the lighter oil myself. lighter oil flows faster and that helps with cooling internal parts in my opinion. I've been using the Driven HR2 in mt FE, Y block, 223 I6 and 302 in Mustang for a few years now and no problems. Others will have different opinions and experience of course.
I set timing by total mechanical advance about 36 degrees and just let initial end up where ever it does which is usually around 12.
Glad things are smoothing out for you.

 

10w-30 should be more than enough for your engine...….if you can find 5w-30 or 0w-30 that would be even better but you will be ok (since it will flow on startup much faster)....BTW, congrats on the engine!!!!!!!!!!!!!!!!!!!!!

 

What is your intended driving climate? Summer temps? How bad are the winters?