Bad valve spring day..

Where's the valve?

427 Fords were notorious for dropping exhaust valves due to the sodium filled stems fracturing.

I never heard of 351c's being particularly susceptible to this but there are now so many aftermarket components going into them durability is becoming a bigger issue than ever.

A failure like this USUALLY takes out the piston, the connecting rod (gets bent) and the cylinder head combustion chamber gets pound on by the valve and destroys it?

The D2AE-CA blocks are thin enough that often the bore cylinder cracks as well.

Nope. This one isn't going to polish out.

Sorry to hear of your troubles.

No valve to be seen, one of the CompCams valve locks was broken in 2. These are PAC 1255X-16 Racing RPM series beehive single springs, OD 1.445”, ID 0.731”, max lift 0.70”. Spring height is great, no spring bind, not near hitting the valve seal. A few gouges on the bottom of the Yella Terra rocker but spins nice still.

I used a breaker bar earlier to turn the engine to check the timing so I was still hoping the valve was still in one piece and just slipped down the guide, wrong..

Top of #4 piston..

The valve stem, thankfully was in the intake manifold. This is a Ferrea F6189 6000 Competition 2.19” swirl polished head, 11/32” stem, EV8 forged stainless intake valve.

Interesting. It's better than I would have thought?

Compcams is one of the companies I am having issues with because they have virtually no quality control checking.

They won't tell you where the components are made and it certainly isn't by them.

All the old "texts" of how the American "engine builders" would use various methods for checking components to me just comes home to roost now?

None of these companies want to pay for a human to do quality checking.


My story of Carrier (air conditioners) having a 50% failure rate at start up just keeps coming back.

The company went non-union and "off shore" to reduce production costs. Before they were in a 10 to 15% failure rate.

Doesn't make sense to me unless they are just dumping responsibility on someone else?

Compcams just dumped it on you?

The camshaft has grooves, difficult to say if how bad. Comp Cams custom mechanical roller camshaft, Grind# FC2314F/2318FR110
Duration @ 0.050 250 Intake - 258 Exhaust. Gross lift 0.640”, Lobe separation 110.0
 Cam in @ 105 1/2 cl. 
Crower 66218E Enduramax Solid roller lifters with needleless roller bushing
 look good and spin nicely. The pushrods roll nicely so might be okay, CompCams Hi-Tech 3/8" 0.080" seamless wall.
#4 bore has 2 small dents from the valve head / stem. In the picture of the head you might be able to see the gouge the valve stem made as it was pounded out of the intake port. Aluminium is in combustion chamber and intake manifold.
Engine is now out and will be crated up to send back to Kuntz and Co who built the engine, 1 year, ~2,000 miles ago.

I have been in contact with Scott Cook who made the heads and intake. He said he will repair and re-cnc the head. I will send the head and engine to Jim Kuntz and let him repair it, he has the expertise and hopefully quicker when adding in the shipping time to Australia. I did not have any oil or water leaks, oil in water or visa-a-versa. The Mahle piston can be replaced and hopefully the block saved, my original 15,000 mile-r.

Wow - you don't mess around.

Sorry to see and hear the bad news. It looks like it could have been a lot worse, but it's certainly bad enough.

Rocky

I feel for you... So sorry to see this. Looks like what happened to my fresh engine after only 980 miles or so. PAC Beehive spring broke and dropped the valve because the beehive springs have no damper to retain the valve if the spring or keeper fails. The RCA on my engine revealed some of the valve springs were out of spec, meaning they reached a coil bind situation with my cam even though my cam lift was well within the advertised capabilities of the springs.

Be sure your engine builder checks the compressed spring height of each spring. Your Beehive springs have advertised specs of:
Max Coil Bind: 1.210
Max Lift: .700
And your cam has 0.640” of gross lift. It would appear you have a sufficient safety margin, but everything's gotta be checked. I thought the same thing with my beehive springs and lift and trusted the advertised spec for the valve springs without measuring each one, so I ran into a coil bind situation with my engine.

Good luck, and keep us posted.

THANKS for posting the pictures & relaying the conditions found.

A GREAT reminder as per Garth, Doug's & many other experiences is that ...DON'T TRUST ANY advertised specifications, seemingly & SADLY quality is a long forgotten memory, & an individual's due-diligence & personal inspection, measuring, testing of each & every individual component is mandatory!...Mark

quote:

Originally posted by 1Rocketship:
THANKS for posting the pictures & relaying the conditions found.

A GREAT reminder as per Garth, Doug's & many other experiences is that ...DON'T TRUST ANY advertised specifications, seemingly & SADLY quality is a long forgotten memory, & an individual's due-diligence & personal inspection, measuring, testing of each & every individual component is mandatory!...Mark

While I agree that the assembly of the valve train needs to be checked at each and every step of assembly, that is doable and necessary by me or your builder, it is not possible during that assembly to verify BY ME (or your builder) that each and every component meets the minimum specification that the manufacturer intended. The manufacturer HAS to do that.

This has become even more of an issue now with attempts at much higher horsepower engines and as a result coming closer to the ultimate yield stresses of ALL of the components.

These are nothing less than ultimate race engines being put into street use and they have even under the best conditions a much shorter usable life span.

The answer is to just back off on some of these components like solid roller camshafts.

No one seems to heed the cautions? Now everyone has me reviewing my own valve train and cam specs?

Solid roller camshafts on the street are just disasters waiting to happen. The disaster IS going to happen. The only question is when, where and HOW bad? I just see them as a common denominator to be avoided.

Again. I am sorry for the loss. This just plain sucks.

Can you please elaborate on why solid roller cams are disastrous?

If the lash is checked regularly, shouldn't they last?

I can totally understand there being a "finer edge", like if not adjusted properly or allowed to have enough lash to start hammering stuff, but why else is solid roller so bad for the street?

My engine is a case example here as we all know, but I think there were some other factors in play in my engine's case (like abuse, and overreving, and age).

I always thought the main difference between solid and hydraulic was solids were capable of more performance (higher rpm's), but needed to be regularly adjusted, religiously.

What else about solid roller cams is so bad?

Just more stuff to go bad?

What about the solid roller cam on Bdud's engine caused this failure?

I think there is too much weight to the valve train. Too much "mass" to be technically correct.

If you look at bdud's cam lobes, they are already scoured. At what, 1,000 miles?

Show me someone with profiles like the two of yours that has got some real miles on the engine and doesn't need to keep going under the valve covers after every run.

Do you think you are imagining this? What is the common denominator in both engines? Maybe the cam?

I suppose that I am just old, old school but I feel there is no place for a roller cam like those on the street?

Those are just "Pro-street" engines and need the maintenance of a Pro Stock race engine. What's the point?

Just my perspective. It doesn't mean I am right. It does mean I was entirely right (for me) in staying with a flat tappet, solid lifter cam. I understand that one.

I don't understand why these solid rollers fail at all, but to me, it's undeniable?

How many miles did Roger say he had on that engine?


If that was my engine, that cam would have been long gone. My neighbor would be lucky not to find it thrown over the fence. I am not as patient with this stuff.

I didn't have the opportunity to spec my engine out, so I'm stuck with what I bought.

I can see what you are saying though. Mainly people are building race engines for street use, and race engines, while they make more power, burn out faster. Is that it in a nutshell?

That's a fair statement I think. People are going to disagree with that. I would love to think that it wouldn't matter what was spec'd but it does.

You mentioned 40 weight oil. To me that isn't a yellow flag, it's a red flag and if I don't pay attention to that probably a black flag sooner than later.

quote:

.... race engines, while they make more power, burn out faster. Is that it in a nutshell?

I don't have a race engine, but I have to throw in this quote from Blade Runner...

".....The light that burns twice as bright burns half as long - and you have burned so very, very brightly, Roy Mike" (and BDUD)


I loved that movie!

Rocky

Relatively speaking, Extreme valve spring pressure & severe camshaft profiles/ramping are kryptonite to Superman's engine.

That is why exotic engines utilize dual overhead camshafts per cylinder head & 4 valves per cylinder to eliminate the necessity of having to resort to extreme valve spring pressures & HUGE camshaft profiles to develop 2HP per cubic inch of displacement ratios at the sacrifice of engine longevity ...Mark

quote:

Originally posted by Rocky:

quote:

.... race engines, while they make more power, burn out faster. Is that it in a nutshell?

I don't have a race engine, but I have to throw in this quote from Blade Runner...

".....The light that burns twice as bright burns half as long - and you have burned so very, very brightly, Roy Mike" (and BDUD)

Rocky

GREAT MOVIE!!!...& I will add like the eventual end of a HIGHLY Stressed Race Engine..."Time to DIE!!!"...Mark

https://www.youtube.com/watch?v=HU7Ga7qTLDU